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Jason is a biological scientist and project manager with nearly 20 years of professional experience and has held positions with Florida Fish and Wildlife Research Institute, U.S. Fish and Wildlife Service, Florida Museum of Natural History, nonprofit institutions, county government, and private consulting firms. Mr. Seitz holds degrees in Fisheries Technology, Aquatic Ecology, and Soil and Water Science with an emphasis on interdisciplinary sciences.  His specialties include fish biology and ecology, bioaccumulation risk assessments using models, NEPA and ESA documentation, technical writing, and project management. Mr. Seitz has published biological research studies in regional and international science journals.


Jason is a biological scientist and project manager with nearly 20 years of professional experience and has held positions with Florida Fish and Wildlife Research Institute, U.S. Fish and Wildlife Service, Florida Museum of Natural History, nonprofit institutions, county government, and private consulting firms. Mr. Seitz holds degrees in Fisheries Technology, Aquatic Ecology, and Soil and Water Science with an emphasis on interdisciplinary sciences.  His specialties include fish biology and ecology, bioaccumulation risk assessments using models, NEPA and ESA documentation, technical writing, and project management. Mr. Seitz has published biological research studies in regional and international science journals.

Florida’s Introduced Nonindigenous and Invasive Mollusks (Clams and Snails): Final Installment of Our 3-part Series on Biological Invasions in Florida

 

This article is a repost from 2015, it discusses the species of introduced mollusks (bivalves and gastropods, better known as clams and snails) of Florida’s terrestrial and aquatic habitats along with a general discussion of the possible effects of biological invasions on native wildlife and habitats.  The first part of this three-part series was on introduced fishes in the state, and the second was on introduced amphibians and reptiles.  This discussion on introduced mollusks of Florida will wrap up our series!

As of this writing, at least 31 species of nonindigenous mollusks representing 17 families have been introduced to Florida (Exhibit 3).  Of these, about 68% have established breeding populations in one or more counties.  There are at least 5 species of introduced clams and 26 species of introduced snails, including terrestrial, freshwater, and marine species.  Of these mollusks, about 68% have established breeding populations in one or more counties.  Examples of established invasive species include the Asian green mussel (Perna viridis) (Exhibit 1) and the giant East African snail (Achatina fulica) (Exhibit 2).  

Exhibit 1 of JCS Introduced Mollusks Writeup 040115

 

Some well-known negative effects of introduced snails are large-scale consumption and decimation of native vegetation and out-competing native species through direct competition for limited resources and through predation on their eggs and young. 

The giant East African snail (Achatina fulica) (Exhibit 2) is a member of a family that contains the largest land snails in the world (Abbott 1989).  The species was first introduced to Florida in 1966 when a young boy brought three live snails from Hawaii (where it is also introduced) to Miami as pets.  Upon discovery of the smuggled snails, the boy’s grandmother released the snails into her garden.  Over the next several years the snails multiplied and spread to neighboring lands.  Florida state agricultural authorities were eventually alerted to the establishment of this destructive species and the species was eradicated by 1972 to the tune of $300,000 (Abbott 1989) to more than $1 million (FDACS 2011).  Between 1966 and 1972, the three specimens brought to Florida by the boy had multiplied to over 18,000 snails.  One specimen of the Miami colony reportedly measured a whopping seven inches in shell length (Abbott 1989)!  

Exhibit 2 of JCS Introduced Mollusks Writeup 040115

 

In September 2011, the giant East African snail was found to have been reestablished in Miami after the Florida Department of Agriculture and Consumer Services responded to a call from a Miami homeowner.  Within 6 months, over 40,000 snails were collected in Miami by state and federal authorities (USDA 2012).  Although authorities are working hard to remove all the individuals of this species from Florida, the eradication will prove very difficult and the likelihood of complete eradication currently appears low.

The giant East African snail is introduced and invasive in several other parts of the world, including Hawaii and other islands in the Pacific, the Philippines, Madagascar, and parts of Asia.  The species is known to consume some 500 species of plants in both agricultural and natural areas.  Because the snail requires large amounts of calcium to grow and strengthen its great shell, the species causes damage to plaster and stucco while consuming these products for their calcium content.  It is a known carrier of a parasitic nematode that is capable of spreading meningitis in humans (FDACS 2011). 

The parasitic nematode known as rat lungworm (Angiostrongylus cantonensis) is carried by the giant East African snail and has an interesting life cycle.  The larvae are ingested by the snail (the intermediate host of the worm) when feeding on rat feces (don’t ask).  The larvae grow and approach maturity inside the snail.  It takes the consumption of an infected snail by a rat (the definitive host) for the parasitic nematode to complete its life cycle by reaching maturity and producing eggs inside the rat.  The mature nematode eggs hatch into larvae while still within the rat and are expelled with the rat’s feces.  People can become infected by eating undercooked or raw (who eats raw snails?) infected snails.  People may also become infected by eating raw produce such as lettuce that contains a small snail or slug.  An infected person cannot transmit the disease to other people.  Infection of rat lungworm in humans is rare in the continental United States, but at least one case was recorded in 1993 in New Orleans where a boy ingested a raw snail (apparently on a dare) and became infected with rat lungworm.  The parasitic nematode is host-specific and humans are not its intended host, so the parasite typically dies inside an infected person, even without treatment.  However, the symptoms range from headache, muscle aches, stiff neck, skin irritation, fever, nausea, and vomiting until the parasite dies (CDC 2010).  

 

In 2012, a captive orangutan (Pongo sp.) housed in Miami was found to have been infected with the rat lungworm.  The animal had a history of eating snails.  Researchers from the University of Florida collected snails and rat feces from around the area where the orangutan was housed and examined the samples for evidence of the parasitic nematode.  Several of the snails and all of the rat feces tested positive for rat lungworm (UF 2015).  The species of snails found to have been infected included the introduced species Asian trampsnail (Bradybaena similaris), garden zachrysia (Zachrysia provisoria), and the striate drop (Alcadia striata) (J. Slapcinsky, Florida Museum of Natural History, Gainesville, FL, pers. comm. 03/03/015).

Although reducing the effects of invasive nonindigenous species (such as those listed in Exhibit 3) is an important part of restoration and management efforts in natural areas of Florida and elsewhere, introduced mollusks are typically a lower priority than other organisms, such as invasive plants or fishes, except when they are known carriers of disease or damage agricultural crops or other property.  Nonetheless, invasive organisms of all kinds can cause significant stress to native ecosystems and biological invasion is widely viewed as a major cause of the reduction in native plant and animal diversity (Elton 1958, Wilcove et al. 1998).  Invasive species are known to affect most natural areas of the United States (Villazon 2009) and worldwide (Sala et al. 2000).

It should go without saying that the intentional introduction of any nonindigenous species, whether it be a plant or animal and regardless of size or assumed innocuousness, should never be attempted.  The reasons are many and the costs can be severe in terms of biological effects, human health, and economic impacts.  Nonindigenous species introduced to new areas have the capacity to explode in numbers and outcompete native species for limited resources such as food, water, and shelter.  Native species are at a competitive disadvantage because they have not had time to evolve defense mechanisms that would otherwise allow them to successfully compete against the introduced species.  The introduced species can have a competitive edge where it is introduced outside its native range partly because these species lack the predators they would have in their native range.  This idea was coined fairly recently by scientists with the term ‘predator release’.  The competition between native and nonindigenous species can result in the extinction of native species, spread of diseases and parasites, and displacement of whole communities, and may even cause physical changes to the environment.

 

 Jasons 1Jasons 2Jasons 3Jasons 4

jasons 5

 

Sources:

Abbott, R.T.  1989. Compendium of Landsnails.  A Color Guide to More than 2,000 of the World’s Terrestrial Shells.  American Malacologists, Inc., Melbourne, FL.

Centers for Disease Control (CDC).  2010.  Parasites – Angiostrongyliasis (Also Known as Angiostrongylus Infection) [online resource].  Accessed 03/24/15 at http://www.cdc.gov/parasites/angiostrongylus/‌gen_info/faqs.html#whatangiostrongylus#whatangiostrongylus.

Elton, C.S.  1958.  The Ecology of Invasions by Animals and Plants. Methuen and Co., Ltd., Strand, London.

Florida Department of Agriculture and Consumer Services (FDACS).  2011.  Florida Department of Agriculture and Consumer Services Identified Giant African Land Snails in Miami-Dade County [online resource].  Accessed 03/24/15 at http://www.freshfromflorida.com/News-Events/Press-Releases/2011-Press-Releases/Florida-Department-of-Agriculture-and-Consumer-Services-Identifies-Giant-African-Land-Snails-in-Miami-Dade-County.

Florida Museum of Natural History (FLMNH).  2015.  Invertebrate Zoology Master Database [online resource].  Accessed 03/23/15 at http://www.flmnh.ufl.edu/scripts/dbs/malacol_pub.asp.

 Sala, O.E. F.S. Chapin, J.J. Armesto, E. Berlow, J. Bloomfield, R. Dirzo, E. Huber-Sanwald, L.F. Huenneke, R.B. Jackson, A. Kinzig, R. Leemans, D.M. Lodge, H.A. Mooney, M. Oesterheld, N.L. Poff, M.T. Sykes, B.H. Walker, M. Walker, and D.H. Wall.  2000.  Global biodiversity scenarios for the year 2100. Science 287:1770–1774.

Seitz, J.C.  2014.  Assessing Stream-mediated Seed and Shoot Dispersal of Invasive Plants in an Urban Riparian Wetland [thesis].  University of Florida, Gainesville, FL.

University of Florida (UF).  2015.  UF Researchers: Rare Parasite Colonizing Snails in South Florida [online resource].  Accessed 03/24/15 at http://news.ufl.edu/archive/2015/02/uf-researchers-rare-parasite-colonizing-snails-in-south-florida.html#prettyPhoto.

U.S. Department of Agriculture (USDA).  2012.  Escargot? More like Escar-No! [online resource].  Accessed 03/24/15 at http://blogs.usda.gov/2012/04/19/escargot-more-like-escar-no/.

U.S. Geological Survey (USGS).  2015.  NAS – Nonindigenous Aquatic Species [online resource].  Accessed 03/23/15 at http://nas.er.usgs.gov/queries/SpeciesList.aspx?Group=Mollusks&Sortby=1&state=FL.

Villazon, K.A.  2009.  Methods to Restore Native Plant Communities after Invasive Species Removal: Marl Prairie Ponds and an Abandoned Phosphate Mine in Florida.  MS thesis, University of Florida, Gainesville, FL.

Wilcove, D.S., D. Rothstein, J. Dubow, A. Phillips, and E. Losos.  1998.  Quantifying threats to imperiled species in the United States. Bioscience 48:607–615.

Wilson, L.D. and L. Porras.  1983.  The Ecological Impact of Man on the South Florida Herpetofauna.  The University of Kansas Museum of Natural History Special Publication No. 9, University of Kansas, Lawrence, KS.

 

 

 

 

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Florida’s Introduced Nonindigenous and Invasive Amphibians and Reptiles: Part 2 of a 3-part Series on Biological Invasions in Florida

This article was first written and posted in 2015. We decided to dust it off and repost it. Enjoy!

This article discusses the species of introduced herpetofauna (amphibians and reptiles) of Florida’s terrestrial and aquatic habitats along with a general discussion of the possible effects of biological invasions on native wildlife and habitats.  The first part of this three-part series was on introduced fishes in the state.  The final part of the series will be on introduced mollusks (bivalves and gastropods, or clams and snails & slugs) of Florida. 

As of this writing, at least 110 species of nonindigenous herpetofauna (colloquially called ‘herptiles’ for short) representing 34 families have been introduced to Florida (Exhibits 1 and 4).  Of the species introduced to Florida, about 43% are now considered to have established breeding populations in one or more counties (Exhibit 2).  This amounts to 47 established herptile species in Florida as of this writing.  Both urban and natural areas of Florida are affected by these biological invaders.  For example, the first reticulated python (Python reticulatus) observed in Florida was during the 1980s, where it was seen living under a house in Miami.  This species has since been observed and (or) collected in several other areas of Florida, although it is not known whether the species has established self-sustaining breeding populations (Exhibit 3).   Lizards are the most successful group and account for the majority (72%) of established herptiles in Florida today.  The list in Exhibit 4 below contains the species known to have been introduced, although it is important to note that new species are introduced on a regular basis in Florida, so the list is constantly expanding.  Most introduced herptiles are native to the tropics (Wilson and Porras 1983).  The fact that Florida’s climate is subtropical is a major reason why many introduced species have successfully established themselves in the state.  Nonindigenous herptiles have been introduced via a variety of mechanisms:

  • Stowaways in shipments of ornamental plants or produce
  • Intentional or accidental release by pet dealers or owners
  • Intentional or accidental release from zoological parks
  • Intentional release by government agencies to combat nuisance organisms

photo 1 Herptiles.PNG

Exhibit 1.  Percentages per group of introduced species of amphibians and reptiles in Florida today.  Sources: Florida Museum of Natural History (http://www.flmnh.ufl.edu/herpetology/florida-amphibians-reptiles/checklist-atlas/), USGS Nonindigenous Aquatic Species online database (http://nas.er.usgs.gov/queries/SpeciesList.aspx?group=Amphibians&state=FL&Sortby=1), Krysko et al. (2011), J.C.Seitz unpublished data.

photo 2 herptiles.PNG

Exhibit 2.  Percentages per group of introduced species of amphibians and reptiles that are known to have established self-sustaining breeding populations in Florida today.  Sources: Florida Museum of Natural History (http://www.flmnh.ufl.edu/herpetology/florida-amphibians-reptiles/checklist-atlas/), USGS Nonindigenous Aquatic Species online database (http://nas.er.usgs.gov/queries/SpeciesList.aspx?group=Amphibians&state=FL&Sortby=1), Krysko et al. (2011), J.C.Seitz unpublished data.

photo 3 herptiles.PNG

Exhibit 3.  Several sightings and captures of the reticulated python (Python reticulatus) have occurred in Florida counties since the late 1980s, including Broward, Collier, Manatee, Miami-Dade, and Pinellas counties. 

The red pin-shaped symbols above represent the location of a sighting or capture.  The black numbers surrounded by red denote locations where more than one sighting or capture was recorded.  Modified from the UF Department of Wildlife Ecology & Conservation (http://ufwildlife.ifas.ufl.edu/snakes/reticulatedpython.shtml).

Wilson and Porras predicted in the early 1980s that southern Florida would eventually be overrun with introduced exotic wildlife.  The current trends in established and spreading introduced species suggest that these authors may have been right. 

Reducing the effects of invasive nonindigenous species is an important part of restoration and management efforts in natural areas of Florida, United States, and worldwide, as these species cause significant stress to native ecosystems (Adams and Steigerwalt 2010) and biological invasion is widely viewed as a major cause of the reduction in native plant and animal diversity (Elton 1958, Wilcove et al. 1998).  Invasive species are known to affect most natural areas of the United States (Villazon 2009) and worldwide (Sala et al. 2000).

It should go without saying that the intentional introduction of any nonindigenous species, whether it be a plant or animal and regardless of size or assumed innocuousness, should never be attempted.  The reasons are many and the costs can be severe, both in terms of biological effects and economic impacts.  Nonindigenous species introduced to new areas have the capacity to explode in numbers and outcompete native species for limited resources such as food, water, and shelter.  Native species are at a competitive disadvantage because they have not had time to evolve defense mechanisms that would otherwise allow them to successfully compete against the introduced species.  The competition between native and nonindigenous species can result in the extinction of native species, the spread of diseases and parasites, displacement of whole communities, and may even cause physical changes to the environment. 

Exhibit 4.  Nonindigenous amphibians and reptiles recorded in Florida.

Scientific Name

Common Name

Locality Records

Current Status

ANURA

FROGS & TOADS

 

 

BOMBINATORIDAE

FIRE-BELLIED TOADS

 

 

Bombina orientalis

Oriental Fire-bellied Toad

Broward Co.

Unknown

BUFONIDAE

AMERICAN TOADS

 

 

Atelopus zeteki

Panamanian Golden Frog

Miami-Dade Co.

Failed

Duttaphrynus melanostictus

Southeast Asian Toad

Miami-Dade Co.

Failed

Rhaebo blombergi

Columbian Giant Toad

Broward Co. (1963)

Failed

Rhinella marina

Cane Toad

Southern Florida, portions of central and northern Florida

Established (southern FL)

Unknown (elsewhere)

ELEUTERODACTYLIDAE

RAINFROGS

 

 

Eleutherodactylus coqui

Coqui

Miami-Dade Co.

Established

Eleutherodactylus planirostris

Greenhouse Frog

Throughout most of Florida

Established (throughout)

Eleutherodactylus portoricensis

Forest Coqui

Miami-Dade Co. (1964)

Collected

HYLIDAE

TREEFROGS

 

 

Litoria caerulea

Australian Green Treefrog

Broward, Collier, & Miami-Dade Co.

Unknown

Osteopilus septentrionalis

Cuban Treefrog

Throughout most of Florida

Established (most of FL)

Pachymedusa dacnicolor

Mexican Leaf Frog

Miami-Dade Co. (1964)

Failed

Pseudacris sierra

Sierran Chorus Frog

Hillsborough & Miami-Dade Co.

Unknown

HYPEROLIIDAE

SEDGE AND BUSH FROGS

 

 

Afrixalus fornasini

Fornasini's Spiny Reed Frog

Broward Co.

Failed

MICROHYLIDAE

NARROWMOUTH TOADS

 

 

Kaloula pulchra

Malaysian Painted Frog

Broward Co.

Unknown

PIPIDAE

TONGUELESS FROGS

 

 

Hymenochirus boettgeri

Zaire Dwarf Clawed Frog

Miami-Dade Co.

Failed

Xenopus laevis

African Clawed Frog

Brevard, Hillsborough, & Miami-Dade Co.

Unknown

AMPHIUMIDAE

AQUATIC SALAMANDERS

 

 

Amphiuma tridactylum

Three-toed Amphiuma

Broward Co.

Unknown

SALAMANDRIDAE

TRUE SALAMANDERS AND NEWTS

 

 

Cynops orientalis

Oriental Fire-bellied Newt

Broward & Sumter Co.

Unknown (Broward Co.)

Collected (Sumter Co.)

Cynops pyrrhogaster

Japanese Fire-bellied Salamander

Miami-Dade Co.

Failed

Notophthalmus viridescens viridescens

Red-spotted Newt

Miami-Dade Co.

Failed

Pachytriton labiatus

Paddle-Tail Newt

Broward Co.

Failed

TESTUDINES

TURTLES & TORTOISES

 

 

BATAGURIDAE

BATAGURID TURTLES

 

 

Ocadia sinensis

Chinese Stripe-necked Turtle

 Alachua Co. (1972)

Eradicated

Rhinoclemmys pulcherrima

Central American Ornate Wood Turtle

Manatee Co.

Failed

Rhinoclemmys punctularia

Spot-legged Wood Turtle

Miami-Dade Co.

Established (Miccosukee Indian Reservation)

Collected (Parrot Jungle Trail, Jungle Island)

CHELIDAE

SOUTH AMERICAN SIDE-NECKED TURTLES

 

 

Chelus fimbriatus

Matamata

Broward Co.

Failed

Platemys platycephala

Twist-necked Turtle

Collier Co.

Collected

EMYDIDAE

POND TURTLES

 

 

Chrysemys dorsalis

Southern Painted Turtle

Alachua & Miami-Dade Co.

Unknown

Chrysemys picta

Western Painted Turtle

Jackson, Miami-Dade, & Orange Co.

Unknown (Jackson Co.)

Failed (Miami-Dade Co.)

Collected (Orange Co.)

Glyptemys insculpta

Wood Turtle

St. Johns Co.

Failed

Graptemys barbouri

Barbour's Map Turtle

Leon Co.

Collected

Graptemys ernsti

Escambia Map Turtle

Orange Co.

Unknown

Graptemys ouachitensis

Ouachita Map Turtle

Miami-Dade & Palm Beach Co.

Collected (Miami-Dade Co.)

Unknown (Palm Beach Co.)

Graptemys pseudogeographica

False Map Turtle

Brevard, Columbia, Gilchrist, & Miami-Dade Co.

Failed (Miami-Dade Co.)

Unknown (elsewhere)

Trachemys dorbigni

Brazilian Slider

Miami-Dade Co.

Failed

Trachemys scripta callirostris

Columbian Slider

Miami-Dade & Monroe Co.

Failed (Miami-Dade Co.)

Unknown (Monroe Co.)

Trachemys scripta elegans

Red-eared Slider

Throughout most of Florida

Established (throughout)

Trachemys scripta scripta

Yellow-bellied Slider

Broward, Lee, & Miami-Dade Co.

Established (Lee Co.)

Unknown (Broward & Miami-Dade Co.

Trachemys stejnegeri malonei

Inagua Slider

Miami-Dade Co.

Failed

KINOSTERNIDAE

MUD & MUSK TURTLES

 

 

Kinosternon scorpioides

Scorpion Mud Turtle

Miami-Dade Co.

Failed

Staurotypus salvinii

Pacific Coast giant musk turtle

Miami-Dade Co.

Unknown

Pelusios subniger

East African Black Mud Turtle

Miami-Dade Co.

Collected

PELOMEDUSIDAE

AFRICAN SIDE-NECKED TURTLES

 

 

Podocnemis lewyana

Magdalena River Turtle

Miami-Dade Co.

Failed

Podocnemis sextuberculata

Six-tubercled River turtle

Miami-Dade Co.

Failed

Podocnemis unifilis

Yellow-spotted River Turtle

Miami-Dade Co.

Failed

TESTUDINIDAE

LAND TORTOISES

 

 

Chelonoidis denticulata

Yellowfoot Tortoise

Collier Co.

Collected

TRIONYCHIDAE

SOFTSHELL TURTLES

 

 

Apalone spinifera

Spiny Softshell

Miami-Dade Co.

Unknown

CROCODYLIA

CROCODILES & ALLIGATORS

 

 

ALLIGATORIDAE

ALLIGATORS

 

 

Caiman crocodilus

Spectacled Caiman

Broward, Miami-Dade, Palm Beach, & Seminole Co.

Established (Broward & Miami-Dade Co.)

Unknown (elsewhere)

Paleosuchus palpebrosus

Cuvier's Smooth-fronted Caiman

Miami-Dade Co.

Failed

Paleosuchus trigonatus

Schneider's Smooth-fronted Caiman

Miami-Dade Co.

Failed

CROCODYLIDAE

CROCODILES

 

 

Crocodylus niloticus

Nile Crocodile

Hendry & Miami-Dade Co.

Failed

Mecistops cataphractus

African Slender-snouted Crocodile

Miami-Dade Co.

Failed

SQUAMATA

AMPHISBAENIANS, LIZARDS, & SNAKES

 

 

CORYTOPHANIDAE

HELMET LIZARDS

 

 

Basiliscus vittatus

Brown Basilisk

Nine counties in southern FL

Established (Broward, Collier, Glades, Indian River, Miami-Dade, Palm Beach, & St. Lucie Co.)

Unknown (elsewhere)

IGUANIDAE

IGUANAS

 

 

Ctenosaura pectinata

Mexican Spinytail Iguana

Broward & Miami-Dade Co.

Established (Miami-Dade Co.)

Unknown (Broward Co.)

Ctenosaura similis

Black Spinytail Iguana

Nine coastal counties in southern FL

Established (most coastal counties in southern FL)

Unknown (elsewhere)

Iguana iguana

Green Iguana

Throughout coastal southern FL and along Lake Okeechobee, isolated areas elsewhere in FL

Established (many coastal counties in southern FL)

Unknown (northern & central FL)

PHRYNOSOMATIDAE

NORTH AMERICAN SPINY LIZARDS

 

 

Phrynosoma cornutum

Texas Horned Lizard

Spottily distributed throughout FL

Established (Duval Co. & western panhandle coastal areas)

Unknown (elsewhere)

POLYCHROTIDAE

ANOLES

 

 

Anolis chlorocyanus

Hispaniolan Green Anole

Broward & Palm Beach Co.

Established (Broward Co.)

Unknown (Palm Beach Co.)

Anolis cristatellus

Puerto Rican Crested Anole

Broward & Miami-Dade Co.

Established (Miami-Dade Co.)

Unknown (Broward Co.)

Anolis cybotes

Largehead Anole

Miami-Dade, Broward, & Martin Co.

Established (Miami-Dade Co.)

Unknown (Broward & Martin Co.)

Anolis distichus

Bark Anole

Most of coastal southern FL

Established (most of coastal southern FL)

Anolis equestris

Knight Anole

Most of coastal southern FL, spottily distributed in inland counties

Established (most of coastal southern FL)

Anolis garmani

Jamaican Giant Anole

Miami-Dade Co.

Established (Miami-Dade Co.)

Anolis porcatus

Cuban Green Anole

Miami-Dade & Monroe Co.

Possible hybridization with A. carolinensis (Miami-Dade & Monroe Co.)

Anolis sagrei

Brown Anole

Throughout peninsula and in at least 6 counties in panhandle

Established (most of FL)

Anolis trinitatis

St. Vincent Bush Anole

Miami-Dade Co.

Unknown

TROPIDURIDAE

LAVA LIZARDS

 

 

Leiocephalus carinatus

Northern Curlytail Lizard

15 counties in peninsular FL

Established to unknown throughout

Leiocephalus schreibersii

Red-sided Curlytail Lizard

Broward, Charlotte, & Miami-Dade Co.

Unknown

AGAMIDAE

AGAMID LIZARDS

 

 

Agama agama

African Rainbow Lizard

9 counties in peninsular FL

Established to unknown throughout

Calotes cf. versicolor

Variable Bloodsucker

Broward & St. Lucie Co.

Unknown (Broward Co.)

Established (St. Lucie Co.)

Leiolepis bellinana

Butterfly Lizard

Miami-Dade Co.

Unknown (Miami-Dade Co.)

CHAMAELEONIDAE

CHAMELEONS

 

 

Chamaeleo calyptratus

Veiled Chameleon

Alachua, Collier, Lee, & Hendry Co.

Unknown (Alachua & Collier Co.)

Established (Hendry & Miami-Dade Co.)

Furcifer oustaleti

Oustalet’s Chameleon

Miami-Dade Co.

Established (Miami-Dade Co.)

SPHAERODACTYLIDAE

NEW WORLD GECKOS

 

 

Gonatodes albogularis

Yellowhead Gecko

Broward, Miami-Dade, Monroe, & St. Lucie Co.

Likely established (Monroe Co.)

Failed (Broward, Miami-Dade, & St. Lucie Co.)

Sphaerodactylus argus

Ocellated Gecko

Monroe Co.

Established

Sphaerodactylus elegans

Ashy Gecko

Miami-Dade & Monroe Co.

Established (Miami-Dade & Monroe Co.)

GEKKONIDAE

WALL GECKOS

 

 

Gekko badenii

Golden Gecko

Broward Co. (Hollywood)

Unknown

Gekko gecko

Tokay Gecko

Spottily distributed between FL Keys north to Tallahassee

Established (spottily between FL Keys to Tallahassee)

Hemidactylus frenatus

Common House Gecko

Broward, Lee, Miami-Dade, & Monroe Co.

Established (Broward, Lee, Miami-Dade, & Monroe Co.)

Hemidactylus garnotti

Indo-Pacific House Gecko

Throughout southern, central, & northern FL peninsula; a few counties in panhandle

Established (throughout peninsula)

Unknown (panhandle)

Hemidactylus mabouia

Tropical House Gecko

Throughout southern FL, also parts of central and northern FL

Established (southern FL, parts of central and northern FL)

Hemidactylus platyurus

Asian Flat-tailed House Gecko

Alachua, Broward, Lee, Miami-Dade, & Pinellas Co.

Established (locally in vicinity of reptile dealerships)

Hemidactylus turcicus

Mediterranean Gecko

Throughout FL

Established (throughout)

Lepidodactylus lugubris

Mourning Gecko

Lee, Miami-Dade, & St. Lucie Co.

Unknown

Phelsuma grandis

Madagascar Giant Day Gecko

Broward, Lee, Monroe, & Palm Beach Co.

Established (Monroe & Palm Beach Co.)

Unknown (Broward & Lee Co.)

PHYLLODACTYLIDAE

PHYLLODACTYLID GECKOS

 

 

Tarentola annularis

Ringed Wall Gecko

Lee, Leon, Broward, & Miami-Dade Co.

Eradicated (Leon Co.)

Unknown (elsewhere)

Tarentola mauritanica

Moorish Gecko

Broward Co.; possibly Lee & Miami-Dade Co.

Unknown

TEIIDAE

WHIPTAILS

 

 

Ameiva ameiva

Giant Ameiva

Broward, Collier, Miami-Dade, & Monroe Co.

Established (Broward, Collier, Miami-Dade, & Monroe Co.)

Aspidoscelis motaguae (formerly Cnemidophorus motaguae)

Giant Whiptail

Miami-Dade Co.

Unknown, possibly established (Miami-Dade Co.)

Cnemidophorus lemniscatus complex

Rainbow Whiptail

Miami-Dade Co.

Unknown, possibly established (Miami-Dade Co.)

Tupinambis merianae

Argentine Giant Tegu

Southern FL, spottily recorded in central and northern FL

Established (Hillsborough, Miami-Dade, & Polk Co.)

Unknown (elsewhere)

SCINCIDAE

SKINKS

 

 

Chalcides ocellatus

Ocellated Skink

Pasco & Broward Co.

Established (both counties)

Eutropis multifasciata

Many-lined Sun Skink

Miami-Dade Co.

Unknown

Trachylepis quinquetaeniata

African Five-lined Skink

St. Lucie Co.

Unknown

VARANIDAE

MONITORS

 

 

Varanus albigularis

White-throated Monitor

Miami-Dade, Monroe, Osceola, & Palm-Beach Co.

Unknown

Varanus doreanus

Blue-tailed Monitor

Indian River Co.

Unknown

Varanus exanthematicus

Savannah Monitor

Collier, Hillsborough, Lee, Leon, Marian, Miami-Dade, Orange, Polk, Sarasota, & Seminole Co.

Unknown

Varanus jobiensis

Peach-throated Monitor

Palm Beach & Polk Co.

Unknown

Varanus niloticus

Nile Monitor

Southern FL, parts of central and northern FL

Established (Broward, Lee, Miami-Dade, & Palm Beach Co.)

Unknown (elsewhere)

Varanus salvator

Water Monitor

Alachua, Broward, Pinellas, & St. Johns Co.

Unknown

Varanus salvadorii

Crocodile Monitor

Miami-Dade Co.

Unknown

ACROCHORDIDAE

WORT SNAKES

 

 

Acrochordus javanicus

Javan File Snake

Broward & Miami-Dade Co.

Established (Miami-Dade Co.)

Unknown (Broward Co.)

BOIDAE

BOAS

 

 

Boa constrictor

Boa Constrictor

Southern FL, parts of central and northern FL

Established (Miami-Dade Co. at Charles Deering Estate)

Unknown (elsewhere)

Eunectes murinus

Green Anaconda

Collier & Osceola Co., possibly Monroe Co.

Collected (Collier & Osceola Co.)

Unknown (Monroe Co.)

Eunectes notaeus

Yellow Anaconda

Collier, Miami-Dade, & Monroe Co.

Collected (Monroe Co.)

Unknown (Collier & Miami-Dade Co.)

PYTHONIDAE

PYTHONS

 

 

Python bivittatus

Burmese Python

Southern FL, parts of central and northern FL

Established (Broward, Collier, Hendry, Miami-Dade, Monroe, & Palm Beach Co.)

Unknown (elsewhere)

Python regius

Ball Python

Collier Co.

Unknown

Python reticulatus

Reticulated Python

Broward, Collier, Manatee, Miami-Dade, & Pinellas Co.

Unknown

Python sebae

Northern African Rock Python

Miami-Dade & Sarasota Co.

Established: Miami-Dade Co.

Unknown: Sarasota Co.

COLUBRIDAE

COLUBRID SNAKES

 

 

Erpeton tentaculatus

Tentacled Snake

Broward Co.

Failed

TYPHLOPIDAE

BLINDSNAKES

 

 

Ramphotyphlops braminus

Brahminy Blindsnake

Central & southern FL, spottily distributed in northern FL

Established (southern, central, portions of northern FL)

Unknown (elsewhere)

Sources: Florida Museum of Natural History (http://www.flmnh.ufl.edu/herpetology/florida-amphibians-reptiles/checklist-atlas/), USGS Nonindigenous Aquatic Species online database (http://nas.er.usgs.gov/queries/SpeciesList.aspx?group=Amphibians&state=FL&Sortby=1), Krysko et al. (2011), J.C.Seitz unpublished data.

Sources:

Adams, C.R. and N.M. Steigerwalt.  2010.  Research Needs and Logistic Impediments in Restoration, Enhancement, and Management Projects: A Survey of Land Managers. Publication ENH1161 [online resource].  Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL.  Accessed 11/21/10 at: http://edis.ifas.ufl.edu/ep423.

Elton, C.S.  1958.  The Ecology of Invasions by Animals and Plants.  Methuen and Co., Ltd., Strand, London.

Florida Museum of Natural History.  2014.  Checklist & Atlas of Amphibians and Reptiles in Florida [online resource].  Accessed 02/24/15 at http://www.flmnh.ufl.edu/herpetology/florida-amphibians-reptiles/checklist-atlas/.

Krysko, K.L., K.M. Enge, P.E. Moler.  2011.  Atlas of Amphibians and Reptiles in Florida.  Project Agreement 08013, report submitted to Florida Fish and Wildlife Conservation Commission, Tallahassee, FL.

Sala, O.E. F.S. Chapin, J.J. Armesto, E. Berlow, J. Bloomfield, R. Dirzo, E. Huber-Sanwald, L.F. Huenneke, R.B. Jackson, A. Kinzig, R. Leemans, D.M. Lodge, H.A. Mooney, M. Oesterheld, N.L. Poff, M.T. Sykes, B.H. Walker, M. Walker, and D.H. Wall.  2000.  Global biodiversity scenarios for the year 2100.  Science 287:1770–1774.

U.S. Geological Survey.  2015.  NAS – Nonindigenous Aquatic Species [online resource].  Accessed 03/03/15 at http://nas.er.usgs.gov/queries/CollectionInfo.aspx?SpeciesID=963&State=FL.

Villazon, K.A.  2009.  Methods to Restore Native Plant Communities after Invasive Species Removal: Marl Prairie Ponds and an Abandoned Phosphate Mine in Florida.  MS thesis, University of Florida, Gainesville, FL.

Wilcove, D.S., D. Rothstein, J. Dubow, A. Phillips, and E. Losos.  1998.  Quantifying threats to imperiled species in the United States. Bioscience 48:607–615.

Wilson, L.D. and L. Porras.  1983.  The Ecological Impact of Man on the South Florida Herpetofauna.  The University of Kansas Museum of Natural History Special Publication No. 9, University of Kansas, Lawrence, KS.

 

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Florida’s Introduced Nonindigenous and Invasive Fishes: Part 1 of a 3-part Series on Biological Invasions in Florida

This article is a repost from 2015. It discusses the species of introduced fishes in Florida’s freshwater and marine habitats, along with a general discussion of biological invasions as a potential driver of loss-of-habitat functions.  Future articles in the series will discuss introduced mollusks (bivalves and gastropods) and herptiles (amphibians and reptiles) of Florida.

Waterbodies such as streams, lakes, ponds, and oceans are well known for their habitat functions, especially their ability to support aquatic wildlife by providing sustenance and shelter.  A myriad of animals, from tiny arthropods to 12-meter-long whale sharks, rely on native organisms as food.   Many waterbodies support some of the most productive habitats in the world, providing food and shelter for mollusks, crustaceans, fishes, amphibians, reptiles, birds, and mammals, and often serve as vital nursery grounds for these species.  Others are nutrient-poor and relatively unproductive.  Nevertheless, hundreds of imperiled species require aquatic habitats for survival.  Along with their threatened or endangered wildlife, waterbodies themselves are threatened in many ways.  Anthropogenic disturbances include groundwater depletion, reallocation of surface water, nutrient inputs, habitat fragmentation, fire suppression, pollution, land use changes, overharvesting, climate change, dredging, and the introduction of nonindigenous plants and animals (Exhibit 1).

Exhibit 1 of JCS Introduced Fishes Writeup 012815

Reducing the effects of invasive nonindigenous species is an important part of restoration and management efforts in natural areas of Florida, the United States, and worldwide.  These species cause significant stress to native ecosystems (Adams and Steigerwalt 2010), and biological invasion is widely viewed as a major cause of the reduction in native plant and animal diversity (Elton 1958, Wilcove et al. 1998).  Invasive species are known to affect most natural areas of the United States (Villazon 2009) and worldwide (Sala et al. 2000), and aquatic habitats are particularly susceptible to nonindigenous species due in part to the fact that aquatic habitats act as biological sinks, receiving plant and animal genetic material from upstream sources.

As of this writing, at least 192 species of fishes representing 42 families have been introduced to Florida (Exhibit 2).  Nearly all waterbodies are affected by fish introductions, from small wetlands to the Atlantic and Gulf coasts of Florida.  The list below contains the species known to have been introduced, although it is important to note that new species are introduced on a regular basis in Florida, so the list is constantly expanding.  Many species ultimately fail to gain a foothold in Florida, while a smaller number of species successfully establish themselves.  Some have spread like a cancer across the state.  The Brown Hoplo (Hoplosternum littorale) is an example of an introduction that is now established throughout the peninsula of Florida, much to the detriment of native aquatic species that have not had time to adapt to this new competitor for limited resources.  Marine habitats are not immune to biological invasions.  The detrimental effects of the (likely intentional) introduction of two species of invasive lionfishes (Red Lionfish and Devil Firefish [Pterois volitans and P. miles]) are still being determined but likely include direct predation on native fishes, crabs, and shrimps and competition with native reef species for limited resources.  Red Lionfish and Devil Firefish are now firmly established throughout the Atlantic coast of Florida and are actively invading much of the Gulf of Mexico.  The spread of lionfishes throughout the western North Atlantic Ocean is occurring at an unprecedented rate (see Exhibit 3) (Schofield 2010).  Many of the introduced fishes in Florida are from tropical or subtropical areas of Asia and South America, and to a lesser extent, Africa (Idelberger et al. 2010).  The fact that Florida’s climate is also subtropical is a major reason why many introduced species have successfully established themselves in the state. 

It should go without saying that the intentional introduction of any nonindigenous species, whether it be a plant or animal and regardless of size or assumed innocuousness, should never be attempted.  The reasons are many and the costs can be severe, both in terms of biological effects and economic impacts.  Nonindigenous species introduced to new areas have the capacity to explode in numbers and outcompete native species for limited resources such as food, water, and shelter.  Native species are at a competitive disadvantage because they have not had time to evolve defense mechanisms that would otherwise allow them to successfully compete against the introduced species.  The competition between native and nonindigenous species can result in the extinction of native species, the spread of diseases and parasites, and the displacement of whole communities, and may even cause physical changes to the environment. 

Exhibit 2.  Freshwater and marine nonindigenous fishes recorded from Florida.

Scientific Name

Common Name

Locality Records

Current Status

ACANTHURIDAE

SURGEONFISHES

 

 

Acanthurus guttatus

Whitespotted Surgeonfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Acanthurus pyroferus

Chocolate Surgeonfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Acanthurus sohal

Red Sea Surgeonfish

Atlantic Ocean off Broward County

Unknown, not likely to be established

Naso lituratus

Orangespine Unicornfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Zebrasoma desjardinii

Sailfin Tang

Atlantic Ocean off Broward County

Unknown, not likely to be established

Zebrasoma flavescens

Yellow Tang

Atlantic Ocean off Broward, Monroe, & Palm Beach counties

Established off Monroe County, unknown elsewhere

Zebrasoma scopas

Brown Tang

Atlantic Ocean off Broward County

Unknown, not likely to be established

Zebrasoma veliferum

Sailfin Tang

Atlantic Ocean off Monroe & Palm Beach counties

Unknown

Zebrasoma xanthurum

Yellowtail Tang

Atlantic Ocean off Palm Beach County

Unknown

ANABANTIDAE

CLIMBING GOURAMIES

 

 

Anabas testudineus

Climbing Perch

Manatee County

Extirpated

Ctenopoma nigropannosum

Twospot Climbing Perch

Manatee County

Extirpated

ANOSTOMIDAE

HEADSTANDERS

 

 

Leporinus fasciatus

Banded Leporinus

Miami-Dade County

Failed

BALISTIDAE

TRIGGERFISHES

   

Balistoides conspicillum

Clown Triggerfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Rhinecanthus aculeatus

Lagoon Triggerfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Rhinecanthus verrucosus

Bursa Triggerfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

BLENNIIDAE

BLENNIES

 

 

Hypsoblennius invemar

Tessellated Blenny

Atlantic and Gulf coasts off Bay, Broward, Lee, Miami-Dade, Monroe, & Palm Beach counties

Established

CALLICHTHYIDAE

ARMORED CATFISHES

 

 

Callichthys callichthys

Cascarudo

Palm Beach County, Boca Raton

Failed

Corydoras sp.

Corydoras

Miami-Dade County, elsewhere

Failed

Hoplosternum littorale

Brown Hoplo

Most of peninsular Florida

Established

CENTRARCHIDAE

SUNFISHES

 

 

Ambloplites rupestris

Rock Bass

Jackson, Okaloosa, Santa Rosa, & Walton counties

Established

CHAETODONTIDAE

BUTTERFLYFISHES

 

 

Chaetodon lunula

Raccoon Butterflyfish

Atlantic Ocean off Broward & Palm Beach counties

Unknown

Heniochus diphreutes

Schooling Bannerfish

Atlantic Ocean off Broward County

Unknown, not likely to be established

Heniochus intermedius

Red Sea Bannerfish

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

Heniochus sp.

Bannerfish

Atlantic Ocean off Palm Beach County

Unknown

CHANNIDAE

SNAKEHEADS

 

 

Channa argus

Northern Snakehead

Seminole & Volusia counties

Failed

Channa marulius

Bullseye Snakehead

Broward County

Established

CHARACIDAE

TETRAS

 

 

Aphyocharax anisitsi

Bloodfin Tetra

Hillsborough County

Failed

Colossoma macropomum

Tambaqui

Alachua, Bay, Broward, Leon, Pinellas, St. Lucie & Volusia counties

Failed

Colossoma or Piaractus sp.

Unidentified Pacu

Alachua, Broward, Citrus, DeSoto, Duval, Escambia, Holmes, Indian River, Marion, Miami-Dade, Pinellas, & Volusia counties

Failed

Gymnocorymbus ternetzi

Black Tetra

Hillsborough County

Failed

Hyphessobrycon eques

Serpae Tetra

Bay County

Failed

Metynnis sp.

Metynnis

Collier & Martin counties, elsewhere

Established (Martin Co.)

Failed (Collier Co.)

Moenkhausia sanctaefilomenae

Redeye Tetra

Hillsborough County

Failed

Piaractus brachypomus

Pirapatinga, Red-Bellied Pacu

Alachua, Brevard, DeSoto, Hillsborough, Martin, Monroe, Orange, Osceola, Polk, Sarasota, St. Lucie, & Walton counties

Unknown (Monroe Co.)

Failed (all other counties)

Piaractus mesopotamicus

Small-Scaled Pacu

Lee County

Failed

Pygocentrus nattereri

Red Piranha

Miami-Dade & Palm Beach counties

Failed (Miami-Dade Co.)

Eradicated (Palm-Beach Co.)

Pygocentrus or Serrasalmus sp.

Unidentified Piranha

Florida (not specified)

Collected

Serrasalmus rhombeus

White Piranha

Alachua & Miami-Dade counties, elsewhere

Eradicated to failed

CICHLIDAE

CICHLIDS

 

 

Aequidens pulcher

Blue Acara

Hillsborough County

Extirpated

Amphilophus citrinellus

Midas Cichlid

Alachua, Broward, Hillsborough, & Miami-Dade counties

Failed (Alachua Co.)

Established (elsewhere)

Archocentrus nigrofasciatus

Convict Cichlid

Alachua & Miami-Dade counties, elsewhere

Failed or eradicated throughout

Astatotilapia calliptera

Eastern Happy

Broward & Palm Beach counties

Established (both counties)

Astronotus ocellatus

Oscar

Much of southern FL

Established

Cichla ocellaris

Butterfly Peacock Bass

Much of southern FL

Established

Cichla temensis

Speckled Pavon

Palm Beach County, elsewhere in southern FL

Failed

Cichlasoma bimaculatum

Black Acara

Much of southern FL

Established

Cichlasoma octofasciata

Jack Dempsey

Alachua, Brevard, Broward, Hillsborough, Indian River, Levy, Manatee, & Palm Beach counties

Established (most counties)

Cichlasoma salvini

Yellowbelly Cichlid

Broward & Miami-Dade counties

Established

Cichlasoma trimaculatum

Threespot Cichlid

Hillsborough & Manatee counties

Failed (Hillsborough Co.)

Extirpated (Manatee Co.)

Cichlasoma urophthalmus

Mayan Cichlid

Much of southern Florida

Established

Geophagus sp.

Eartheater

Miami-Dade County

Failed

Hemichromis letourneuxi

African Jewelfish

Much of southern Florida

Established

Herichthys cyanoguttatum

Rio Grande Cichlid

Brevard, Hillsborough, Lee, Miami-Dade, Monroe, Pinellas, & Polk counties

Established

Heros severus

Banded Cichlid

Broward & Miami-Dade counties

Established

Melanochromis auratus

Golden Mbuna

Hillsborough County

Unknown

Oreochromis aureus

Blue Tilapia

Much of peninsular FL

Established

Oreochromis mossambicus

Mozambique Tilapia

Much of peninsular FL

Established

Oreochromis niloticus

Nile Tilapia

Alachua, Brevard, Gadsden, Hardee, Hendry, Highlands, Jackson, Osceola, Putnam, & Sarasota counties

Established (Alachua Co.)

Unknown (elsewhere)

Oreochromis sp.

Tilapia Species

Brevard County

Unknown

Oreochromis, Sarotherodon, Tilapia sp.

Tilapia

Glades County, elsewhere

Collected

Parachromis managuensis

Jaguar Guapote

Much of southern FL

Established

Pseudotropheus socolofi

Pindani

Miami-Dade County

Extirpated

Pterophyllum scalare

Freshwater Angelfish

Palm Beach County

Failed

Sarotherodon melanotheron

Blackchin Tilapia

Much of southern FL

Established

Telmatochromis bifrenatus

Lake Tanganyika Dwarf Cichlid

Oklawaha County

Failed

Thorichthys meeki

Firemouth Cichlid

Brevard, Broward, Hillsborough, Miami-Dade, Monroe, Miami-Dade, & Palm Beach counties

Established (Broward Co.)

Failed or extirpated (elsewhere)

Tilapia buttikoferi

Zebra Tilapia

Miami-Dade County

Established

Tilapia mariae

Spotted Tilapia

Much of southern FL

Established

Tilapia sp.

Unidentified Tilapia

Brevard County

Established

Tilapia sparrmanii

Banded Tilapia

Hillsborough County, elsewhere

Failed

Tilapia zillii

Redbelly Tilapia

Brevard, Lake, Miami-Dade, & Polk counties

Established (Brevard & Miami-Dade Co.)

Extirpated or failed (elsewhere)

CLARIIDAE

LABYRINTH CATFISHES

 

 

Clarias batrachus

Walking Catfish

Much of southern FL

Established

COBITIDAE

LOACHES

 

 

Misgurnus anguillicaudatus

Oriental Weatherfish

Much of southern FL

Established

Pangio kuhlii

Coolie Loach

Hillsborough County

Failed

CYPRINIDAE

CARPS AND MINNOWS

 

 

Barbonymus schwanenfeldii

Tinfoil Barb

Palm Beach County, elsewhere

Failed

Carassius auratus

Goldfish

Alachua, Clay, Miami-Dade, & Putnam counties

Unknown

Ctenopharyngodon idella

Grass Carp

Throughout FL

Stocked as triploid, no evidence of establishment

Cyprinus carpio

Common Carp

Much of northern FL

Established

Danio rerio

Zebra Danio

Hillsborough & Palm Beach counties

Failed

Devario malabaricus

Malabar Danio

Hillsborough & Miami-Dade counties, elsewhere

Failed

Hybopsis cf. winchelli

Undescribed Clear Chub

Gadsden County

Failed

Hypophthalmichthys nobilis

 

Bighead Carp

Bay & Palm Beach counties

Failed

Labeo chrysophekadion

Black Sharkminnow, Black Labeo

Not specified

Failed

Leuciscus idus

Ide

Not specified

Failed

Luxilus chrysocephalus isolepis

Striped Shiner

Escambia & Santa Rosa counties

Established

Nocomis leptocephalus bellicus

Bluehead Chub

Escambia & Santa Rosa counties

Established

Notemigonus crysoleucas

Golden Shiner

Ochlocknee drainage

Established

Notropis baileyi

Rough Shiner

Escambia & Santa Rosa counties

Established

Notropis harperi

Redeye Chub

Leon County

Failed

Pethia conchonius

Rosy Barb

Palm Beach County, elsewhere

Failed

Pethia gelius

Dwarf Barb

Palm Beach County, elsewhere

Failed

Pimephales promelas

Fathead Minnow

Hillsborough, Leon, Marion, Palm Beach, & Polk counties

Unknown or extirpated throughout

Systomus tetrazona

Tiger Barb

Miami-Dade County, elsewhere

Failed

Tinca tinca

Tench

Unspecified

Failed

DORADIDAE

THORNY CATFISHES

 

 

Oxydoras niger

Ripsaw Catfish

Miami-Dade County

Failed

Platydoras costatus

Raphael Catfish

Unspecified

Collected

Pterodoras granulosus

Granulated Catfish

Pinellas County

Failed

Pterodoras sp.

Thorny Catfish

Pinellas County

Failed

Platax orbicularis

Orbiculate Batfish

Broward, Lee, Miami-Dade, Monroe, & Palm Beach counties

Eradicated to unknown

ERYTHRINIDAE

TRAHIRAS

 

 

Hoplias malabaricus

Trahira

Hillsborough County

Eradicated

GRAMMATIDAE

BASSLETS

 

 

Gramma loreto

Fairy Basslet

Atlantic Ocean off Broward, Monroe, Palm Beach, & Duval counties; also in Gulf of Mexico (unspecified counties)

Established (throughout)

HELOSTOMATIDAE

KISSING GOURAMIES

 

 

Helostoma temminkii

Kissing Gourami

Hillsborough & Palm Beach counties

Failed

HEMISCYLLIIDAE

BAMBOOSHARKS

 

 

Chiloscyllium punctatum

Brownbanded Bambooshark

Atlantic Ocean off Palm Beach County

Unknown, not likely to be established

HEPTAPTERIDAE

SEVEN-FINNED CATFISHES

 

 

Rhamdia quelen

Bagre

Miami-Dade County

Failed

Rhamdia sp.

Bagre De Rio

Miami-Dade County

Unknown

ICTALURIDAE

NORTH AMERICAN CATFISHES

 

 

Ictalurus furcatus

Blue Catfish

Calhoun, Escambia, Gilchrist, Okaloosa, & Washington counties, elsewhere in northern FL

Established (most of area)

Failed (Okaloosa Co.)

Unknown (Washington Co.)

Pylodictis olivaris

Flathead Catfish

Calhoun, Escambia, Liberty, Gulf, Holmes, Jackson, Walton, & Washington counties, elsewhere in northern FL

Established (several areas)

Failed or unknown elsewhere

LORICARIIDAE

SUCKERMOUTH ARMORED CATFISHES

 

 

Ancistrus sp.

Bristlenosed Catfish

Miami-Dade County

Established

Farlowella vittata

Twig Catfish

Hillsborough County

Unknown

Glyptoperichthys gibbiceps

Leopard Pleco

Alachua County

Unknown

Hypostomus plecostomus

Suckermouth Catfish

Broward, DeSota, Hillsborough, Miami-Dade, & Polk counties

Established (most of area)

Unknown (Hillsborough Co.)

Hypostomus sp.

Suckermouth Catfish

Hillsborough, Martin, Miami-Dade, Palm Beach, Pinellas, & Seminole counties, elsewhere

Established (throughout)

Pterygoplichthys anisitsi

Paraná Sailfin Catfish

Brevard, Marion, Okeechobee, & St. Johns counties

Established

Pterygoplichthys disjunctivus

Vermiculated Sailfin Catfish

Much of southern FL

Established

Pterygoplichthys multiradiatus

Orinoco Sailfin Catfish

Much of southern FL

Established

Pterygoplichthys pardalis

Amazon Sailfin Catfish

DeSota, Glades, Hardee, Hillsborough, Lee, Miami-Dade, Okeechobee, Palm Beach, Sarasota, & St. Lucie counties

Established

Pterygoplichthys sp.

Sailfin Catfish

Much of central and southern FL

Established (much of area)

MASTACEMBELIDAE

FRESHWATER SPINY EELS

 

 

Macrognathus siamensis

Spotfin Spiny Eel

Miami-Dade & Monroe counties

Established (throughout)

MORONIDAE

TEMPERATE BASSES

 

 

Morone chrysops

White Bass

Much of peninsular FL

Established

Morone chrysops x M. saxatilis

Sunshine Bass

Much of northern and central FL

Stocked

Morone saxatilis

Striped Bass

Gadsden, Hernando, Lake, Martin, Orange, Polk, & Walton counties

Established (Gadsden, Hernando, Polk, & Walton counties)

Failed, extirpated, or collected (elsewhere)

NOTOPTERIDAE

FEATHERFIN KNIFEFISHES

 

 

Chitala ornata

Clown Knifefish

Lake, Palm Beach, & Pinellas counties

Failed (Lake & Pinellas Co.)

Established (Palm Beach Co.)

OSPHRONEMIDAE

GOURAMIES

 

 

Betta splendens

Siamese Fighting Fish

Manatee & Palm Beach counties, elsewhere

Failed (throughout)

Colisa fasciata

Banded Gourami

Not specified

Failed

Colisa labiosa

Thicklipped Gourami

Hillsborough County

Failed

Colisa lalia

Dwarf Gourami

Hillsborough & Palm Beach counties

Failed

Macropodus opercularis

Paradise Fish

Palm Beach County

Failed

Osphronemus goramy

Giant Gourami

Not specified

Collected

Trichogaster leerii

Pearl Gourami

Palm Beach County

Failed

Trichogaster trichopterus

Three-Spot Gourami

Miami-Dade & Palm Beach counties

Failed

Trichopsis vittata

Croaking Gourami

Palm Beach County

Established

OSTEOGLOSSIDAE

AROWANAS

 

 

Osteoglossum bicirrhosum

Silver Arowana

Broward, Monroe, & Osceola counties

Failed

PANGASIIDAE

SHARK CATFISHES

 

 

Pangasianodon hypophthalmus

Iridescent Shark

Hillsborough County, elsewhere

Failed

PERCIDAE

PERCHES AND DARTERS

 

 

Perca flavescens

Yellow Perch

Gadsden & Liberty counties, Apalachicola drainage

Established

Sander canadensis

Sauger

Gadsden County

Established

Sander vitreus

Walleye

Orange County

Failed

PIMELODIDAE

LONG-WHISKERED CATFISHES

 

 

Leiarius marmoratus

(no common name)

Miami-Dade County

Unknown

Phractocephalus hemioliopterus

Redtail Catfish

Bay County, elsewhere

Failed

POECILIIDAE

LIVEBEARERS

 

 

Belonesox belizanus

Pike Killifish

Much of southern FL

Established (throughout)

Gambusia affinis

Western Mosquitofish

Alachua County

Failed

Poecilia kykesis

Péten Molly

Hillsborough & Palm Beach counties

Failed

Poecilia latipunctata

Tamesí Molly

Hillsborough County

Failed

Poecilia reticulata

Guppy

Alachua, Brevard, Hillsborough, & Palm Beach counties

Unknown (Alachua Co.)

Failed (Brevard Co.)

Extirpated (Hillsborough & Palm Beach Co.)

Poecilia sphenops

Mexican Molly

Not specified

Failed

Xiphophorus hellerii

Green Swordtail

Brevard, Hillsborough, Indian River, Manatee, Palm Beach, Polk, & St. Johns counties

Established (throughout)

Xiphophorus hellerii x X. maculatus

Red Swordtail

Brevard & Hillsborough counties

Established

Xiphophorus hellerii x X. variatus

Platyfish/Swordtail

Not specified

Locally established

Xiphophorus maculatus

Southern Platyfish

Alachua, Brevard, Hillsborough, Indian River, Manatee, Palm Beach, & St. Lucie counties

Established (throughout except Indian River & Manatee Co.)

Unknown (Indian River & Manatee Co.)

Xiphophorus sp.

Platyfish

Brevard & Hillsborough counties

Unknown (Brevard Co.)

Established (Hillsborough Co.)

Xiphophorus variatus

Variable Platyfish

Alachua, Brevard,  Hillsborough, Manatee, Marian, Miami-Dade, & Palm Beach counties

Established (throughout)

Xiphophorus xiphidium

Swordtail Platyfish

Not specified

Collected

POLYODONTIDAE

PADDLEFISHES

 

 

Polyodon spathula

Paddlefish

Jackson County & Apalachicola River

Failed

POLYPTERIDAE

BICHIRS

 

 

Polypterus delhezi

Barred Bichir

Broward County

Failed

POMACANTHIDAE

ANGELFISHES

 

 

Pomacanthus annularis

Blue Ringed Angelfish

Broward County

Unknown

Pomacanthus asfur

Arabian Angel

Broward County

Unknown

Pomacanthus imperator

Emperor Angelfish

Broward & Miami-Dade counties

Unknown

Pomacanthus maculosus

Yellowbar Angelfish

Broward & Palm Beach counties

Unknown

Pomacanthus semicirculatus

Semicircle Angelfish

Broward & Palm Beach counties

Unknown

Pomacanthus xanthometopon

Bluefaced Angel

Broward County

Unknown

POMACENTRIDAE

DAMSELFISHES

 

 

Dascyllus aruanus

Whitetail Damselfish

Palm Beach County

Eradicated

Dascyllus trimaculatus

Three Spot Damselfish

Palm Beach County

Unknown

Salmonidae

Salmon and Trout

 

 

Oncorhynchus mykiss

Rainbow Trout

Okaloosa & Walton counties

Stocked (1968)

Salmo trutta

Brown Trout

Not specified

Failed

SCATOPHAGIDAE

SCATS

 

 

Scatophagus argus

Scat

Levy & Martin counties

Collected

SCORPAENIDAE

SCORPIONFISHES

 

 

Pterois volitans &

P. miles (combined here due to morphological similarity)

Red Lionfish &

Devil Firefish

Throughout much of the Atlantic coast of Florida, nearshore to at least 60 miles offshore, less commonly encountered along the Gulf coast

Established (Atlantic coast)

Likely established (Gulf coast [see Schofeild 2010 for more info.])

Serranidae

Sea Basses

 

 

Cephalopholis argus

Peacock Hind

Broward, Monroe, & Palm Beach counties

Unknown

Chromileptes altivelis

Panther Grouper

Brevard, Broward, Palm Beach, & Pinellas counties

Unknown

Epinephelus ongus

White-Streaked Grouper

Palm Beach County

Unknown

SYNBRANCHIDAE

SWAMP EELS

 

 

Monopterus albus

Asian Swamp Eel

Hillsborough, Manatee, & Miami-Dade counties

Established (throughout)

TETRAODONTIDAE

PUFFERS

 

 

Arothron diadematus

Masked Pufferfish

Palm Beach County

Failed

ZANCLIDAE

MOORISH IDOLS

 

 

Zanclus cornutus

Moorish Idol

Monroe & Palm Beach counties

Unknown

Sources: Schofield (2010), USGS Nonindigenous Aquatic Species online database (http://nas.er.usgs.gov/queries/SpeciesList.aspx?group=Fishes&state=FL&Sortby=1)

Exhibit 3 of JCS Introduced Fishes Writeup 012815

Below is a link to an interactive map showing the spread of the Red Lionfish and the Devil Firefish in the western North Atlantic from the 1980s to 2013:

http://nas.er.usgs.gov/queries/FactSheets/LionfishAnimation.aspx

Sources:

Adams, C.R. and N.M. Steigerwalt.  2010.  Research Needs and Logistic Impediments in Restoration, Enhancement, and Management Projects: A Survey of Land Managers. Publication ENH1161 [online resource]. Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL. Accessed 11/21/10 at: http://edis.ifas.ufl.edu/ep423.

Didham, R.H., J.M. Tylianakis, M.A. Hutchison, R.M. Ewers, and N.J. Gemmell. 2005. Are invasive species the drivers of ecological change? Trends in Ecology and Evolution 20(9):470–474.

Elton, C.S. 1958. The Ecology of Invasions by Animals and Plants. Methuen and Co., Ltd., Strand, London.

Idelberger, C.F., C.J. Stafford, and S.E. Erickson.  2011.  Distribution and abundance of introduced fishes in Florida’s Charlotte Harbor estuary.  Gulf and Caribbean Research 23:13–22.

Sala, O.E. F.S. Chapin, J.J. Armesto, E. Berlow, J. Bloomfield, R. Dirzo, E. Huber-Sanwald, L.F. Huenneke, R.B. Jackson, A. Kinzig, R. Leemans, D.M. Lodge, H.A. Mooney, M. Oesterheld, N.L. Poff, M.T. Sykes, B.H. Walker, M. Walker, and D.H. Wall. 2000. Global biodiversity scenarios for the year 2100. Science 287:1770–1774.

Schofield, P.J.  2010. Update on geographic spread of invasive lionfishes (Pterois volitans [Linnaeus, 1758] and P. miles [Bennett, 1928]) in the western North Atlantic Ocean, Caribbean Sea and Gulf of Mexico. Aquatic Invasions 5, Supplement 1:S117–S122.  http://www.aquaticinvasions.net/2010/Supplement/AI_2010_5_S1_Schofield

U.S. Geological Survey.  2015. NAS – Nonindigenous Aquatic Species [online resource].  Accessed 01/23/15 at http://nas.er.usgs.gov/queries/CollectionInfo.aspx?SpeciesID=963&State=FL.

Villazon, K.A. 2009. Methods to Restore Native Plant Communities after Invasive Species Removal: Marl Prairie Ponds and an Abandoned Phosphate Mine in Florida. MS thesis, University of Florida, Gainesville, FL.

Vitousek, P.M., C.M. D’Antonio, L.L. Loope, and R. Westbrooks. 1996. Biological invasions as global environmental change. American Scientist 84:468–478.

Vitousek, P.M., H.A. Mooney, J. Lubchenco, and J.M. Melillo. 1997. Human domination of Earth’s ecosystem. Science 277:494–499.

Wilcove, D.S., D. Rothstein, J. Dubow, A. Phillips, and E. Losos.  1998.  Quantifying threats to imperiled species in the United States. Bioscience 48:607–615.

 

 

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Dispelling Myths about the Coyote in Florida, Or, Probably More Than You Wanted to Know about the Coyote in Florida

Dispelling Myths about the Coyote in Florida,

Or,

Probably More Than You Wanted to Know about the Coyote in Florida

If you live in Florida you’ve probably heard people talk about coyotes (Canis latrans [Exhibits 1 and 2]) in Florida.  Below are facts gleaned from the literature regarding this interesting mammal.

How Did the Coyote Get Its Name?

The accepted common name ‘coyote’ comes from the Aztec term for the species, Coyotl.  Other names used for this species in North America include coyóte (Mexican), brush-wolf, prairie-wolf, American jackal, and little wolf (Beebe 1964).

 

Coyote pic 1

Exhibit 1A Coyote (Canis latrans) Photographed in Arizona

Photo courtesy of Wikipedia Commons.

Why Did Coyotes Expand Their Range into the Eastern United States and Florida?

Most of us know that coyotes are not native to the eastern U.S., including Florida.  Their range has historically been limited to the western U.S. (Layne 1997).  Humans eliminated gray wolves and red wolves from the eastern U.S. in the early- to mid-1900s, with the red wolf being last recorded in Florida at that time (Beebe 1964).  Wolves were apparently a major constraint on the range of the coyote, so their recent absence from parts of the U.S. allowed for the natural expansion of the coyote’s range.  Thus, the expansion of the coyote into Florida and elsewhere in the eastern U.S. is most likely due to humans extirpating the wolves in this area.  Humans may have helped the coyote become established in Florida through accidental release or escape and (or) intentional release (Layne 1997), such as for hunting. 

Here’s a timeline of the presence of the coyote in Florida:

  • Pre-historic: Coyote fossils found in Florida geology dating to the Pleistocene (2.6 million to 11,700 years ago) (Webb 1974)
  • European colonization: No evidence of the species in Florida (Layne 1997)
  • 1970s: Coyotes were already well established in northern Florida (Layne 1997)
  • Early 1980s: The species was distributed through the middle of the Florida peninsula, from Hamilton County to Polk County (Brady and Campell 1983)
  • 1982: First sighting in Highlands County in southern Florida (Layne 1997)
  • 1988: The coyote’s range extended south to Broward and Collier counties (Wooding and Hardisky 1990)
  • 1995: A survey of coyote tracks by R. McBride found they were widely distributed in Highlands and Polk counties (Layne 1997)
  • 1991: Coyotes killed or trapped in Charlotte and Desoto counties (Layne 1997)
  • 2007: Coyotes documented in every county in Florida, and populations in Florida continue to increase (McCown and Scheick 2007)

What Habitats Do Coyotes Use Most Often?

In Florida, coyotes frequent improved pastures, native prairies, and citrus groves according to a survey by R. McBride cited in Layne (1997).  Den sites are located along brushy slopes, areas of thick undergrowth of vegetation, inside hollow logs, within rocky ledges, and burrows made either by adult coyotes or by other mammals.  Tunnels leading to the den may be 5 to 25 feet long (1.5 to 7.5 meters).  The den chamber itself measures about 1 foot (0.3 meters) in width and is commonly located 3.3 feet (1 meter) below-ground.  Coyotes may undertake seasonal migrations between habitats in some areas of North America (Novak 1999).

What Is the Average Size of the Coyote’s Home Range?

A coyote can cover a distance of about 2.5 miles (4 km) in a night while searching for a meal.  They traveled an average distance of 19.3 miles (31 km) from the point of capture in a tagging study in Iowa, but one individual covered a whopping 200 miles (323 km) during that study (Novak 1999).  A coyote tagged in south-central Canada traveled a record distance of 338 miles (544 km) from the point of capture (Carbyn and Paquet 1986).  Home range sizes vary greatly, from 3 to 31 square miles (8 to 80 km2).  Males have larger home ranges than do females, and male ranges overlap one another considerably.  Females ranges are smaller and do not overlap with those of other females (Novak 1999).

What’s the Average Population Density for Coyotes?

Population densities are generally between 0.1 and 0.2 coyotes per square mile (0.2 to 0.4 individuals/km2), but can be as high as 1.2 individuals per square mile (2.0/km2) in areas having extremely favorable conditions (Knowlton 1972, Bekoff 1977).  A study of coywolves (hybrid of coyote x eastern gray wolf [Canis lupus lycaon]) living north of Boston, Massachusetts, found a very high population density in fall and winter, at 1.1 to 1.3 individuals per square mile (2.9 to 3.4 individuals/km2) and 0.8 individuals per square mile (2.0 individuals/km2), respectively (Way 2011).

When Are Coyotes Most Active?

Coyotes can be active at any time of day or night, but they are mainly nocturnal and crepuscular (Novak 1999) (crepuscular means active around dawn and dusk [insect-eating bats are another example of crepuscular mammals]).

Does a Coyote Sighting Mean They Are More Common in the Area Than in Other Areas?

Coyotes are found in every Florida county.  Their level of abundance cannot be measured merely by anecdotal sightings since coyotes try to blend in with their surroundings and not be seen.  Sightings of coyotes do not necessarily mean that they are more abundant where sighted.  Coyotes are wherever there is suitable habitat, regardless of whether or not they are seen.  A sighting only confirms that coyotes are present.

What Do Coyotes Eat?

Coyotes mainly eat small mammals.  Rabbits and rodents make up the bulk (90%) of their diet in most areas.  Larger animals such as deer are also commonly eaten, but mostly as scavenged carcasses, although sometimes after a chase in which several coyotes worked together to take down the animal.  Other food items include fishes (which they are capable of snatching from streams!), lizards, snakes, birds such as turkeys, insects, grasses, fruits (including watermelon, persimmon, and various wild berries), and seeds (Novak 1999, Coates et al. 2002).  A tracking study conducted in Tucson, Arizona, found that over a 33-day period during November 2005 through February 2006, a group of eight coyotes killed 19 domestic cats (Harris Environmental Group 2015).  This interesting study further strengthens the idea that domestic cats are much better off if kept entirely indoors.  The coyote is also capable of preying on small domestic dogs (McCown and Scheick 2007).  Livestock are occasionally taken but the impact on livestock numbers is minimal (Novak 1999).  In the western U.S., where coyotes share their range with American badgers, the two species have been documented to form hunting partnerships whereby the coyote uses its excellent sense of smell to locate burrowing rodents, and the badger uses its powerful legs and claws to dig out the prey, which they then share (Novak 1999).

How Often Do Coyotes Prey on Domestic Livestock Like Cattle?

It is true that coyotes can kill and consume livestock including calves, poultry, pigs, and goats (Coates et al. 2002).  However, coyotes are not a serious problem to livestock (with the possible exception of sheep [Coates et al. 2002]) in most parts of their range, and reports of livestock damage from this species appear to be driven by popular perception and emotional reactions.  In the words of the past Chief Game Biologist for Mississippi, H.E. Alexander, “Reports of livestock damage from these animals seems to be more dependent on popular attitudes and emotional reactions to conspicuous evidence of depredations at some time and place than on actual fluctuations [of coyote populations]” (Beebe 1964).  Coyotes are not a major concern to livestock producers in Florida according to McCown and Scheick (2007).

What’s the Average Size and Weight of an Adult Coyote?

Adult male coyotes weigh 18 to 44 pounds (8 to 20 kg).  Adult females weigh 15 to 40 pounds (7 to 18 kg).  Coyotes living in northern regions weigh more, on average, than do those living in southern regions of North America (Nowak 1999).  The average weight of a coyote in Alaska is 40 pounds (18 kg), contrasting with the average weight of 25 pounds (11.5 kg) for coyotes living in the deserts of Mexico according to Gier (1975).  An unusually heavy coyote from Canada that weighed 46 pounds (21 kg) was noted by Beebe (1964).  The largest coyotes are those living in the northeastern United States, owing to enhanced nutrition there and (or) hybridization with the gray wolf (Nowak 1999).  In general, coyotes are larger than foxes but smaller than wolves (Coates et al. 2002).

How Fast Can Coyotes Run?

Coyotes are very speedy runners!  Picture this: a coyote racing in the World Championships in Athletics against legendary world record-holder Usain Bolt.  Usain runs a breathtakingly fast time of 9.58 seconds for the 100‑meter sprint.  That’s 23.4 miles per hour (mph) (37.7 km/hour)!  Now, let’s focus on the coyote.  The coyote explodes out of the starting line at a staggering pace, crossing the finish line in about half the time (4.47 seconds) it took Usain to cover the same distance!  That’s right, coyotes are fast and capable of running at speeds of up to 50 mph (80.5 km/hour) (Sooter 1943, Fisher 1975).  Although Novak (1999) gives a top speed of 64 mph (103 km/hour), this is higher than what is stated by most other sources.  Coyotes are clearly one of the fastest terrestrial mammals in North America.

Coyote Reproduction 101

Litter size averages about 6 pups but ranges from 2 to 12 pups.  Large numbers of pups have been found in a single den but were probably the result of litters from more than one female.  Females produce only one litter annually (Novak 1999).  Mating occurs during January through March, and gestation takes about 2 months (Coates et al. 2002).  Parturition (birthing) takes place in spring.  The pups weigh only about 8.8 ounces (250 grams) at birth.  Their eyes don’t open until day 14.  Young emerge from the den within about 3 weeks of birth and are fully weaned at about 9 months, at about which time they approach the weight and size of adult coyotes.  The average life span is less than 6 years, with the most significant mortality being within the first year of life (Coates et al. 2002).  The maximum longevity was recorded at 14.5 years in the wild, but most wild coyotes do not survive this long.  One long-lived captive coyote lived 21 years and 10 months (Jones 1982).

Do Coyotes Sometimes Hybridize with Other Canids?

Coyotes are well known to interbreed with domestic dogs (producing what are called ‘coydogs’).  Coyotes also interbreed with eastern gray wolves (Way 2011) as well as with red wolves (Canis lupus rufus), producing ‘coywolves’.  The offspring produced are fertile. 

What Are the Regulations on Hunting Coyotes in Florida?

The hunting and trapping of coyotes is allowed year-round throughout Florida (http://myfwc.com/‌hunting/season-dates).  However, a permit from the Florida Fish and Wildlife Conservation Commission (FWC) is needed for using steel traps, such as leg-hold traps.  More information on how to apply for a steel trap permit is found at http://myfwc.com/license/wildlife/nuisance-wildlife/steel-traps/.  FWC keeps a list of nuisance-wildlife trappers at https://public.myfwc.com/HGM/NWT/NWTSearch.aspx?.

 

Coyote pic 2

Exhibit 2The California Valley Subspecies of Coyote (Canis latrans clepticus) Photographed in the San Gabriel Mountains of California
Photo courtesy of Justin Johnsen and Wikipedia Commons.

Sources

Beebe, B.F.  1964.  American Wolves, Coyotes, and Foxes.  David McKay Co., Inc., New York, NY.

Bekoff, M.  1977.  Social behavior and ecology of the African Canidae: A review.  Pp. 120–142.  In: M.W. Fox (ed.)  The Wild Canids: Their Systematics, Behavioral Ecology and Evolution.  R.E. Krieger Publishing Co., Inc., Malabar, FL.

Brady, J.R. and H.W. Campell.  1983.  Distribution of coyotes in Florida.  Florida Field Naturalist 11:40–41.

Carbyn, L.N. and P.C. Paquet.  1986.  Long distance movement of a coyote from Riding Mountain National Park.  Journal of Wildlife Management 50:89.

Coates, S.F., M.B. Main, J.J. Mullahey, J.M. Schaefer, G.W. Tanner, M.E. Sunquist, and M.D. Fanning.  2002.  The Coyote (Canis latrans): Florida’s Newest Predator [online resource].  Wildlife Ecology and Conservation Dept. document WEC124, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, UF, Gainesville, FL.  Accessed 04/22/15 at http://edis.ifas.ufl.edu/pdffiles/UW/UW12700.pdf.

Fisher, J.  1975.  The plains dog moves east.  National Wildlife 13(2):1417.

Gier, H.T.  1975.  Ecology and behavior of the coyote (Canis latrans).  Pp. 247–262.  In: M.W. Fox (ed.) The Wild Canids: Their Systematics, Behavioral Ecology, and Evolution.  Van Nostrand Reinhold, New York, NY.

Harris Environmental Group, Inc.  2015.  Coyote’s Eat Cats! [online resource].  Accessed 04/22/15 at http://www.heg-inc.com/2009/08/coyotes-eat-cats/.

Jones, M.L.  1982.  Longevity of captive mammals.  Der Zoologische Garten 52:113–128.

Knowlton, F.F.  1972.  Preliminary interpretations of coyote population mechanics with some management implications.  Journal of Wildlife Management 36:369–382.

Layne, J.  1997.  Nonindigenous mammals. Pp 157–186.  In: D. Simberloff, D.C. Schmitz, and T.C. Brown (eds.), Strangers in Paradise, Impact and Management of Nonindigenous Species in Florida.  Island Press, Washington, D.C.

MacCown, W. and B. Scheick.  2007.  The Coyote in Florida [online resource].  Florida Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Tallahassee, FL.  Accessed 04/22/15 at http://myfwc.com/media/1228800/CoyoteWhitePaperFinal.pdf.

Nowak, R.M.  1999.  Walker’s Mammals of the World, Sixth Edition, Volume I.  The Johns Hopkins University Press, Baltimore, MD.

Sooter, C.A.  1943.  Speed of a predator and prey.  Journal of Mammalogy 24:102–103.

Way, J.G.  2011.  Record pack-density of eastern coyotes/coywolves (Canis latrans x lycaon).  The American Midland Naturalist 165(1):201–203.

Webb, S.D.  1974.  Chronology of Florida Pleistocene mammals.  In: S.D. Webb (ed.), Pleistocene Mammals of Florida.  University Press of Florida, Gainesville, FL.

Wilson, L.D. and L. Porras.  1983.  The Ecological Impact of Man on the South Florida Herpetofauna.  The University of Kansas Museum of Natural History Special Publication No. 9, University of Kansas, Lawrence, KS.

Wooding, J.B. and T.S. Hardisky.  1990.  Coyote distribution in Florida.  Florida Field Naturalist 18:12–14.

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A Brief Summary of Laurel Wilt Disease in Florida and the Southeastern United States

A Brief Summary of Laurel Wilt Disease in Florida and the Southeastern United States

Recently, there has been considerable interest and research regarding the laurel wilt disease, which affects members of the Lauraceae family, most notably red bay (Persea borbonia) and swamp bay (Persea palustris).  This article attempts to summarize the aspects of this disease that are of particular interest to land owners and land managers of Florida and elsewhere in the southeastern United States.

The Story of the Ambrosia Beetle, a Symbiotic Fungus, and the Disease Called Laurel Wilt

The disease Laurel wilt is spread by a nonindigenous beetle called the Asian red bay ambrosia beetle, Xyleborus glabratus.  This beetle measures only about 2 mm in length and is cigar-shaped and amber-brown to black in color.  This species has significantly less hair on its dorsal surface and is shinier than other species of ambrosia beetles.  The female ambrosia beetle spreads a nonindigenous fungus, Raffaelea lauricola, into the sapwood of a tree by boring pinhole-sized holes into the branches or trunk and either actively or passively depositing spores of the fungus in the tunnels.  The fungal spores are carried by the beetle in specialized pouch-like structures called ‘mycangia’ that are located at the base of each mandible.  Both adult and larval ambrosia beetles feed on the fungus growing in the tunnels.  Larvae are white with an amber-colored head.  Unlike most other species of ambrosia beetle, which attack dead or dying trees, the Asian red bay ambrosia beetle attacks healthy trees.  The native range of the fungus includes India, Japan, Taiwan, Burma, Bangladesh, and Myanmar.  As you probably guessed, the Asian red bay ambrosia beetle is native to Asia, including the same countries that the fungus is native to. 

The exact mechanism that causes death to a tree infected with the fungus and symbiont ambrosia beetle to die is unknown.  In simplified terms, the death of the tree is the result of it over-reacting to the presence of the pathogen.

The ambrosia beetle and associated fungus are thought to have arrived in the United States from Asia in untreated wood (such as wooden pallets) or in logs.  They were first detected in the United States in Port Wentworth near Savannah, Georgia, in May 2002.  The disease has since spread throughout the Southeast, from North Carolina south to Florida and west to Mississippi.

Relative Infestations of Laurel Wilt Disease among Infected States

State

Area of Coverage

Notes

Alabama

A few counties in the southwestern portion of the state

First detected in the state in 2011

Florida

Throughout most of the state

First detected in the state in 2005.  Not yet detected in some counties of the panhandle and in some the southwestern portion of the state

Georgia

Many counties in the southeastern portion of the state

First detected in the state in 2002, in Port Wentworth near Savannah

Mississippi

A few counties in the extreme southern part of the state

First detected in the state in 2009

North Carolina

Six counties in the southeastern portion of the state

First detected in the state in 2011

South Carolina

Many counties in the southern and eastern portions of the state

First detected in the state in 2004

What Tree Species Does Laurel Wilt Infect?

Although the beetle is named Asian red bay ambrosia beetle, it actually infects several other species, including both native trees and introduced trees of importance to the agricultural and ornamental plant industries.  Below is a list of species known to be susceptible to Laurel wilt.

Trees and Shrubs Known or Suspected to be Susceptible to Laurel Wilt Disease

Common Name

Scientific Name

Notes

Avocado

Persea americana

Introduced, important agricultural crop, important also to the ornamental plant trade

Lancewood

Ocotea coriacea

May be less susceptible to the disease than other members of the family, based on preliminary testing

Northern spicebush

Lindera benzoin

Pondspice

Litsea aestivalis

State-listed as endangered in Florida; demonstrated experimentally to be susceptible to the disease

Red bay

Persea borbonia

Sustained significant mortality due to the disease

Sassafrass

Sassafras albidum

Swamp bay
(incl. silk bay)

Persea palustris

Sustained significant mortality due to the disease

Southern spicebush (AKA pondberry)

Lindera melissifolia

State-listed as endangered in Florida; demonstrated experimentally to be susceptible to the disease

Summary of the Biology and Symptoms of Laurel Wilt Disease

The female ambrosia beetle, attracted to the smell of a red bay tree, bores into the branches or trunk of the tree and deposits spores of the fungus in the tunnels.  Initial symptoms are wilting of the leaves.  Often, wilting is seen in all the leaves associated with the distal portion of an infected branch.  More and more leaves begin to wilt over time as the disease progresses.  Mild discoloration may be seen in the sapwood and can escalate to extensive black/brown streaking over time.  Frass tubes, looking like white bent straws sticking out from the bark, begin to appear months later as beetle activity increases.  It can take as little as a week for a tree to die from laurel wilt during the warm summer months.

Both adult ambrosia beetles and their larvae feed on the fungus growing in the tunnels.  It takes some 30 days from the time the eggs hatch to the development of adult ambrosia beetles.  Males are smaller than females, lack wings, and are haploid.  Females are winged and are diploid.  The fungus can remain alive inside a standing dead tree for at least 1 year according to recent research.  The biology of laurel wilt disease remains poorly understood, and there is significant research to be done to understand the mechanisms involved in susceptibility and resistance.

Management and Prevention of Laurel Wilt Disease

It is no longer logistically feasible to eradicate or stop the progression of the disease considering how widely distributed it is in the southeastern United States.  However, one way to slow the spread on a given site is to cut down and chip dead trees killed by the disease and place the wood chips into piles.  The fungus was found to die about 2 days following chipping, and the ambrosia beetle population of the tree was found to be reduced by 99% following chipping.  The chipping will also reduce the wood available for female beetles to reproduce.

Use of the fungicide propiconazole (Alamo®), injected into the tree, was found to be only mildly effective (approximately 60% survivorship) at protecting red bay trees from the disease.  This treatment is expensive and testing for use against Laurel wilt has been limited so far.  Best results are achieved by systemic injection before any symptoms of the disease are observed on the tree and the pruning of any diseased areas following treatment.  Another method of injecting fungicide, developed by Arborjet®, involves delivering smaller amounts of fungicide using microinjectors.  The results of the effectiveness of the Arborjet® method have not been published as of this writing.  Similarly, the results of the effectiveness of applying fungicide to the soil around a tree have yet to be published.  Fungicides should be administered only by a knowledgeable professional or by the homeowner and in accordance with the instructions and mixing rates on the label.

Insecticides are unlikely to be useful at protecting a tree again the ambrosia beetle.  Broadcast spraying would be harmful to the environment and to beneficial insects, is not likely to be effective against the ambrosia beetle, and is therefore strongly discouraged. 

An attempt was made to protect some trees in Volusia County, Florida, by spraying Pinesol® as a way of “hiding” the trees from detection by the ambrosia beetle.  Pinesol® spraying took place at about 6‑ to 10‑week intervals.  However, all treated trees eventually contracted the disease and subsequently died.  It is possible that baits may be developed in the future that may be more attractive to the beetles than are the trees, but at this point in time no compounds have been identified for use as baits.

Anyone can help reduce the spread of the ambrosia beetle and the associated Laurel Wilt disease.  Refrain from moving untreated firewood far distances.  The State of Florida prohibits movement of untreated firewood farther than 50 miles within the state.  When camping, buy only local firewood or use certified firewood rather than bringing your own.  When traveling abroad, do not bring back untreated wood products or raw plant parts (including seeds or fruits).

Laurel wilt disease is one of at least a dozen tree diseases and insect pests within Florida or neighboring states.  Minimizing the movement of untreated wood and firewood can help reduce the spread of insect pests and diseases such as the emerald ash borer (kills ash trees), Asian longhorned beetle (kills maples), oak wilt and bot canker of oaks (kills oaks), spiraling whitefly (kills several native and ornamental trees), walnut twig beetle and thousand-cankers disease (kills walnuts), sudden oak death (kills oaks), and others.  The reader is encouraged to visit the website www.dontmovefirewood.org for more information.  

Sources and Further Reading:

Global Invasive Species Database.  2010.  Global Invasive Species Database, Raffaelea lauricola (fungus) [online database].  Accessed 10/17/2014 at http://www.issg.org/database/species/ecology.asp?si=1549&lang=EN.

Global Invasive Species Database.  2010.  Global Invasive Species Database, Xyleborus glabratus (insect) [online database].  Accessed 10/17/2014 at http://www.issg.org/database/species/ecology.asp?si=1536.

Spence, D. and J. Smith.  2013.  The status of Laurel Wilt.  Palmetto 30(3):4–5, 8–10. 

U.S. Department of Agriculture, Forest Service.  2013.  Laurel Wilt Distribution Map [online resource].  Accessed 10/17/2014 at http://www.fs.fed.us/r8/foresthealth/laurelwilt/dist_map.shtml.

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What can fossils tell us about the rock surrounding them?

What can fossils tell us about the rock surrounding them?

Fossil scallops in the Coquille River as a case study

During a benthic survey off the Coquille River, Oregon, in September 2013, ANAMAR was collecting samples of epifauna using a 12-foot otter trawl when suddenly the gear encountered unidentified rock. The trawl net snagged and the cable instantly snapped, losing the gear on the seafloor in about 45 feet of water. Although many attempts were made to recover the trawl using a grapple hook off the deck of the survey vessel (R/V Pacific Storm), the gear was too entangled on the seafloor to be brought up with that method. Directly following completion of the benthic survey, an ANAMAR subcontractor returned to the site and recovered the trawl gear using SCUBA divers. The trawl was still in good shape and the remaining trawl tows were completed for the survey. In addition to finding the trawl gear, the divers also observed several fossil scallop shells embedded in the rock on the seafloor. The fossil scallops were in excellent condition (see images below). The divers were able to pry a few of the fossil shells loose for closer inspection and photography.

 

jasons coquille FILEminimizer

 

 

Because the area where the survey took place is an ocean dredged material disposal site (ODMDS), information on the naturally occurring rocks found there is of interest to agencies tasked with managing the site (U.S. Army Corps of Engineers and U.S. Environmental Protection Agency). For this reason, and also out of personal interest, I began collaborating with paleontologists to determine the identity of the fossil scallops in the hopes of learning more about the rock they were found in. I soon found my answer after contacting specialists at the Burke Museum of Natural History in Seattle, Washington. Dr. Elizabeth Nesbitt, Curator of Paleontology, graciously identified the fossil scallops as either Patinopecten coosensis or P. oregonensis based on photos I sent her. The flared portions of the shell adjacent to the hinge (called auricles) serve as key characteristics differentiating these two species. These fossils lacked auricles so they could not be identified beyond these two species. However, based on the fossils and the associated matrix, Dr. Nesbitt was able to identify the rock formation the fossils were found in!

The rocks and fossils are part of the Empire Formation which is better known from exposures about 20 miles south of the Coquille River at Cape Blanco, Oregon. The Empire Formation, composed mostly of sandstone, along with the fossils it contains, are as old as 12 million years (Miocene), but it is theorized to be closer to 8 to 5 million years (Miocene-Pliocene epoch boundary). Since we know the identity of the rock as being part of the Empire Formation, we therefore know something about its composition. In this case, the rocks that snagged the trawl gear must have been composed of sandstone and some siltstone. This formation represents sands deposited in what was then a small marine basin which now is represented only by Coos Bay. It is probable that other rocks within the ODMDS are also fossiliferous sandstone/siltstone from the Empire Formation.

The above is an example of how fossils can help us infer the identity of the surrounding substrate. In this case, the identity of the fossil scallops, along with the matrix attached to the fossils, were used to pinpoint the exact formation they represent. Knowing the formation, we then were able to learn more about the composition and approximate geological age of surrounding rocks that represent the same formation. All this information came from observing and collecting a handful of fossils incidental to recovering of some equipment from the seafloor!

Interestingly, the French word for scallop is Coquille. Thus the Coquille River, where the fossils were collected, was actually named after a scallop!

Sources:

Ehlen, J. 1967. Geology of state parks near Cape Arago, Coos County, Oregon. The Ore Bin 29(4):61–82.

Nesbitt, E. Department of Paleontology, Burke Museum of Natural History, University of Washington, Seattle, WA. Pers. comm. 12/06/13.

Portell, R.W. Department of Invertebrate Paleontology, Florida Museum of Natural History, University of Florida, Gainesville, FL. Pers. comm. 11/18/13.

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Out of Their Element: What Makes Gulf Sturgeon So Jumpy?

Out of Their Element: What Makes Gulf Sturgeon So Jumpy?

The jumping of Gulf sturgeon (Acipenser oxyrinchus desotoi) on the Suwannee River is well publicized and is widely known among Floridians. Some jumping sturgeon have even caused injuries to unfortunate boaters who get in the way of these armored aerial acrobats. Sturgeon jump most often in the early morning, and each fish averages one jump per day. Jumping is not confined to large individuals either, as fish as small as 1 foot long will jump. Most jumping activity occurs from June to early July, when some reaches of the river can experience as many as 6 to 10 jumps per minute! The most intense jumping occurs when the water level is low, before the summer convective storm season sets in. Yes, the fact that these massive timeless fish jump is not the question here. They jump. We know. What’s not well publicized is why exactly these sturgeon feel the need to jump in the first place.

Gulf sturgeon are not trying to shed ectoparasites as many believe, nor are they trying to capture prey. The jumping is also unrelated to spawning. They are not reacting to the presence of boats.

They loiter in the deep dark pools of the Suwannee River and in other Gulf Slope rivers from April through September and slowly digest the 20 percent of body fat they put on during the previous 6 months of easy living, and easy feeding, in the Gulf of Mexico. When in the Suwannee they seldom feed, so put that fishing pole away.

Resting in the sluggish deep recesses of the Suwannee, Gulf sturgeon are conserving energy. But just hovering above the river bottom requires neutral buoyancy. Similar to how a SCUBA diver adjusts his BC, these fish must add air to the swim bladder. Air slowly leaks out of the swim bladder and is absorbed in the surrounding tissues. To keep from scraping along the bottom and to swim more efficiently in the sluggish current, the swim bladder must be refilled an average of once daily. Since the swim bladder in Gulf sturgeon is connected to the digestive tract by a duct, the bladder can be recharged by gulping air. But how do fishes, being totally aquatic as they are, find any atmospheric air to gulp? Well, we have nearly reached our answer as to why they jump.

Any SCUBA diver knows that you can’t descend easily through the water column with a BC full of air, even with dive weights. By the same principle, a sturgeon can’t just rise gently to the surface, take a big gulp of air, and glide back down into the depths. Did I mention that while sturgeon are lollygagging in the river, they are also chatting up a storm? Call them gabby or chatty, Gulf sturgeon really know how to bend an ear (or otolith, in this case). These fish communicate with one another via a series of snapping sounds. Jumping high up into the air and then falling powerfully back into the water, with a loud report, and swimming directly to the bottom, serves two purposes. The main purpose is to allow the fish to gulp air and yet have enough momentum to reach the river bottom immediately afterward (despite the increased buoyancy from the added air). The secondary purpose may be to communicate. Immediately prior to jumping, these fish emit a series of snapping sounds, and following the belly-flop-style smack when entering the water, the sturgeon emit more snapping sounds. The role jumping plays in sturgeon communication, if any, is far from clear and would be very difficult to prove scientifically. However, it seems probable that these fish are communicating with one another using not just snapping sounds (which have been recorded by U.S. Geological Survey scientists and heard by SCUBA divers), but perhaps also by the splash following a jump. So, the next time you encounter a jumping sturgeon while enjoying a lazy day on the Suwannee, ask it why it jumps. Listen carefully to its answer and don’t be surprised if its response sounds something like “snap, snap-snap, snaaap, snaaap, snap”.

Source and Suggested Reading:

Sulak, K. 2013. Catching air – those magnificent jumping Suwannee sturgeons. American Currents 38(2):23–25.

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Amazing Sawfish of the Past: A brief review of the fossil record of these intriguing animals

Amazing Sawfish of the Past: A brief review of the fossil record of these intriguing animals

All sawfishes are highly modified and elongate rays that swim like a shark and have a long snout with laterally-placed spines. The snout (called a ‘rostrum’) is actually an extension of the skull (known as the ‘chondrocranium’) and the lateral spines are called ‘rostral teeth’ by scientists. Like the rest of the skeleton of the sawfish, the rostrum is composed of cartilage, albeit reinforced with extra calcium. The rostrum and rostral teeth are used in food gathering. The sawfish uses the rostrum to stun prey, such as fishes and invertebrates, which it then sucks into its mouth positioned under the head. There is no cutting or tearing and sawfish can only consume fish and invertebrates that fit into the mouth whole.

The modern sawfish group (family Pristidae) first showed up in the fossil record between the beginning of the Cenozoic (about 66 million years ago) and the beginning of the Eocene (about 56 million years ago). The only exception is the nominal genus Peyeria, which first appeared during the upper Cretaceous (about 100 million years ago). However, the fossil material attributed to the genus Peyeria may actually represent another type of ray—a member of the sharkfin guitarfish family (Rhinidae) such as the bowmouth guitarfish (Rhina ancylostoma).

Living (extant) sawfishes include the following species:

The Knifetooth complex (one species):

  1. Anoxypristis cuspidata (knifetooth sawfish [western Pacific and Indian oceans])

The Smalltooth complex (three species):

  1. Pristis clavata (dwarf sawfish [western Pacific Ocean])
  2. Pristis pectinata (smalltooth sawfish [eastern and western Atlantic Ocean])
  3. Pristis zijsron (green sawfish [western Pacific and Indian oceans])

The Largetooth complex of sawfish has recently been combined into one species:

  1. Pristis pristis (largetooth sawfish [eastern and western Atlantic, eastern and western Pacific, and Indian oceans])

There were also several additional members of the modern sawfish group that are only represented as fossils:

  1. Anoxypristis mucrodens (fossils of Europe, North America, West and East Africa)
  2. Peyeria libyca (nominal species; fossils of northeast Africa including Egypt)
  3. Propristis schweinfurthi (fossils of North and West Africa)
  4. Pristis spp. (at least eight extinct species described; fossils of West and East Africa, Europe, and North America)

Prior to the modern sawfishes, a diverse group of sawfishes (family Sclerorhynchidae) lived during the Cretaceous epoch. Members of the Cretaceous sawfishes had a diverse array of rostral tooth morphologies, ranging from closely-spaced thin spines to widely-spaced massive barbed teeth on sturdy, widened bases. Although most species reached a modest size of not more than 1 meter in total length, fossil rostra measuring well over 1 meter in length have been unearthed in Cretaceous sediments of Morocco.

There are at least 20 genera of Cretaceous sawfishes, including the following:

  1. Ankistrorhynchus (fossils of Europe and North America)
  2. Atlanticopristis (fossils of South America)
  3. Baharipristis (fossils of East Africa)
  4. Biropristis (fossils of South America)
  5. Borodinopristis (a nominal genus of about three species [fossils of North America])
  6. Ctenopristis (fossils of West and East Africa)
  7. Dalpiaza (fossils of West Africa)
  8. Ganopristis (fossils of Europe)
  9. Ischyrhiza (fossils of North and South America)
  10. Kiestus (fossils of North America)
  11. Libanopristis (fossils of Middle East)
  12. Marckgrafia (fossils of West Africa)
  13. Micropristis (fossils of Europe and Middle East)
  14. Onchopristis (fossils of North America, Europe, West and East Africa, Asia, New Zealand)
  15. Onchosaurus (fossils of North America and West Africa)
  16. Plicatopristis (fossils of the Middle East)
  17. Pucapristis (fossils of South America)
  18. Renpetia (fossils of the Middle East)
  19. Schizorhiza (fossils of North America and Middle East)
  20. Sclerorhynchus (fossils of North America and Middle East)

Modern sawfishes and Cretaceous sawfishes evolved independently from the guitarfishes (Rhinobatidae). Thus, while both groups are commonly referred to as sawfish, and both share similar morphological characteristics, they are not closely related. Sawfishes should not be confused with the saw sharks (family Pristiophoridae), which are true sharks and therefore only distantly related to the sawfishes (which are rays, not sharks).

The rostral teeth of Cretaceous sawfishes are attached to the dermis of the rostrum via connective tissue. Their rostral teeth are thought to be continually replaced throughout the life of the animal in the same conveyer-belt fashion as are the oral teeth of all sharks and rays. In contrast, modern sawfishes have rostral teeth firmly embedded in sockets (called ‘alveoli’) and their teeth are not replaced if lost. Cretaceous sawfish rostral teeth are covered with an enamel-like coating along the cusp; this coating is lacking in modern sawfishes. Cretaceous sawfishes also differ from modern sawfishes in that they possess a long, whip-like caudal fin. Although the average fossil remains consist of isolated rostral teeth or oral teeth, some beautiful, fully articulated fossil skeletons have been unearthed in Lebanon quarries.

Sources:

Alroy, J. and M. McClennen. 2013. Paleobiology Database [online resource]. Accessed 06/10/13 online at http://www.paleodb.org/?a=displaySearchColls&type=view.

Faria, V.V., M.T. McDavitt, P. Charvet, T.R. Wiley, C.A. Simpfendorfer, and G.J.P. Naylor. 2013. Species delineation and global population structure of critically endangered sawfishes (Pristidae). Zoological Journal of the Linnean Society 167(1):136–164.

Seitz, J.C. 2013. Fossil Sawfish [online resource]. Accessed 06/10/13 online at http://www.fossilsawfish.com/.

Wueringer, B.E., L. Squire Jr., and S.P. Collin. 2009. The biology of extinct and extant sawfish (Batoidea: Sclerorhynchidae and Pristidae). Reviews in Fish Biology and Fisheries 19:445–464.

Authored by Jason C. Seitz of ANAMAR

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How Many Species of Sawfish Are There in the World Today?

Jason sawfishSawfishes are large highly modified and elongate rays that swim like a shark and have a long snout with laterally-placed spines.  The snout (called a ‘rostrum’) is actually an extension of the skull (known as a ‘chondrocranium’) and the lateral spines are called ‘rostral teeth’ by scientists.  Like the rest of the skeleton of the sawfish, the rostrum is composed of cartilage, albeit reinforced with extra calcium.  The rostrum and rostral teeth are used in food gathering.  The sawfish uses the rostrum to stun fishes and to a lesser extent, invertebrates, which it then sucks into its mouth positioned under the head.  There is no cutting or tearing and sawfish can only consume fish and invertebrates that fit into the mouth whole.  The longest species of sawfish, the green sawfish (Pristis zijsron), is reported to reach a length of 23.9 feet according to Last and Stevens (1994).

Sawfishes can be distinguished from saw sharks (Pristiophurus spp. and Pliotrema warreni) by the lack of barbels, ventrally located gills (versus laterally located), dorso-laterally compressed body, and uniformly sized rostral teeth.  Sawfishes grow much larger than do saw sharks.  Further, sawfishes prefer warm coastal waters while saw sharks inhabit deeper cooler offshore waters.

Living sawfish species are globally distributed in tropical and sub-tropical coastal marine and estuarine waters, and sometimes inhabit rivers and associated freshwater bodies such as Lake Nicaragua.  The center of distribution is the western Pacific including northern Australia and Papua New Guinea. 

All modern sawfish species are considered imperiled and regarded by the International Union for the Conservation of Nature (IUCN) as ‘critically endangered’ with declining populations (www.iucnredlist.org).  Unfortunately, the IUCN is not a regulatory agency and thus no protection is afforded by this group.  Only two species currently have protection under the endangered species act of 1972, and only in waters of the United States.  The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has protected all species of sawfish from international trade of sawfish parts since 2007 (www.cites.org).  However, the confusing taxonomy of modern sawfishes has hampered conservation efforts and such efforts are further disadvantaged by the poorly known geographical population structure.

Until very recently, there were six valid living species worldwide. The Knifetooth Complex of sawfish currently consists of one species:

Anoxypristis cuspidata (knifetooth sawfish [western Pacific and Indian oceans])

 The Smalltooth Complex of sawfish consists of three species:

Pristis clavata (dwarf sawfish [western Pacific Ocean])

Pristis pectinata (smalltooth sawfish [eastern and western Atlantic Ocean])

Pristis zijsron (green sawfish [western Pacific and Indian oceans])

 The Largetooth Complex of sawfish consisted of two species:

Pristis microdon (freshwater sawfish [western Pacific and Indian oceans])

Pristis perotteti (largetooth sawfish [eastern and western Atlantic Ocean, eastern Pacific Ocean])

Some researchers also considered the species Pristis pristis to be a valid member of the Largetooth Complex, although most considered it as an invalid synonym due to problems relating to its original description and lack of voucher specimens in museums (Faria 2007).  Also, the eastern Pacific population of the largetooth sawfish was considered to be a separate species (Pristis zephyreus) by some researchers following molecular phylogenetic work by Faria (2007), although no reliable morphological differences have been found between the eastern Pacific population and largetooth sawfish from the western Atlantic.

The freshwater sawfish and the largetooth sawfish have been problematic for researchers because the two species cannot be reliably differentiated by morphology and thus, these species were differentiated solely by region.  For specimens lacking collection data, this presents a challenge as the species may not be reliably determined at all.  Molecular work has shown that these species group closely together in terms of genetic background (Naylor et al. 2012).

Because of the fact that the largetooth sawfish and the freshwater sawfish are indistinguishable by morphology and share similar genetic backgrounds, it has been very recently proposed by researchers that these two species should be combined.  In a paper published in early 2013 and authored by Faria et al. (2013), all the Largetooth Complex species have been combined into a composite species under the resurrected name of Pristis pristis.  The resurrection of the formerly invalid name of Pristis pristis was based on Rule 23.1 (principle of priority) of the International Code of Zoological Nomenclature, which states that ‘the valid name of a taxon is the oldest available name applied to it’ (International Commission on Zoological Nomenclature 1999).  Since the species name Pristis pristis was published in 1758 (as Squalus pristis by Carl Linnaeus), it precedes the naming of all other Largetooth Complex species.  For this reason and because this name was used as a valid species after 1899, Pristis pristis is proposed by Faria et al. (2013) for use in place of Pristis microdon, Pristis perotteti, and the species of questionable validity, Pristis zephyreus.

Based on Faria et al. (2013), there are now a total of five valid sawfish species:

The Knifetooth complex (one species):

Anoxypristis cuspidata (knifetooth sawfish [western Pacific and Indian oceans])

The Smalltooth complex (three species):

Pristis clavata (dwarf sawfish [western Pacific Ocean])

Pristis pectinata (smalltooth sawfish [eastern and western Atlantic Ocean])

Pristis zijsron (green sawfish [western Pacific and Indian oceans])

The Largetooth complex of sawfish now consists of only one species:

Pristis pristis (largetooth sawfish [eastern and western Atlantic, eastern and western Pacific, and Indian oceans])

It is possible that in the future, changes may occur within the taxonomy of the knifetooth sawfish.  Gene flow between Indian Ocean and western Pacific specimens was found to be very low in a study by Faria et al. (2013).  Specimens from the Indian Ocean were found to have a higher average number of rostral teeth per side (average of 25.6) versus western Pacific specimens (average of 21.2) (faria et al. 2013).  Results of the Faria et al. (2013) study suggest that the knifetooth sawfish may actually represent multiple species.  In fact, a DNA-sequencing based analysis by Naylor et al. (2012) showed that knifetooth sawfish had considerable genetic differences from all other living members of the sawfish family.  This suggests that in the future the knifetooth sawfish may even be placed into a separate family distinct from the other sawfishes.

It is clear that there is still a lot to learn about sawfishes.  Although it is uncertain what changes will occur in sawfish taxonomy, or what new information will come to light from future scientific research, it remains clear that this interesting group of animals will continue to captivate scientists and layman alike for many years to come.

Sources Cited: Faria, V.V.  2007.  Taxonomic Review, Phylogeny, and Geographical Population Structure of the Sawfishes (Chondrichthyes, Pristiformes).  PhD dissertation, Iowa State University, Ames, IA.

Faria, V.V., M.T. McDavitt, P. Charvet, T.R. Wiley, C.A. Simpfendorfer, and G.J.P. Naylor.  2013. Species delineation and global population structure of critically endangered sawfishes (Pristidae).  Zoological Journal of the Linnean Society 167(1):136–164.

International Commission on Zoological Nomenclature.  1999.  International Code of Zoological Nomenclature. The International Trust for Zoological Nomenclature, The Natural History Museum, London, UK.

Last, P.R. and J.D. Stevens.  1994. Sharks and Rays of Australia.  CSIRO Division of Fisheries, Victoria, Australia.

Naylor, G.J.P., J.N. Caira, K. Jensen, K.A.M., Rosana, W.T. White, and P.R. Last.  2012. A DNA sequence-based approach to the identification of shark and ray species and its implications for global elasmobranch diversity and parasitology. Bulletin of the American Museum of Natural History 2012(367):1–262.

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