Aquatics – Fish Identification Texas Envirothon 2015 Fish Identification

Aquatics – Fish Aquatics – Fish IdentificationIdentification

Texas EnvirothonTexas Envirothon20152015

Fish Identification

Texas Edwards Texas Edwards

PlateauPlateau

Karst is a geomorphological structure resulting from the hydrochemical and water erosion of carbonate rock formations.

San Marcos River

Comal River

Guadalupe River

Environmental Environmental ImpactsImpacts

1. Reduced springflows caused by increased pumping, irrigation, human consumption

2. Elimination of habitat – riparian loss, invasive plants

3. Degradation of water quality caused by urban expansion.

4. Increased pressure by recreational users

Healthy StreamHealthy StreamCharacteristics Effects

• Meandering pattern• Habitat diversity• Intact riparian zone

• Natural deposition and erosion

• Species diversity• Stream shading

Degraded StreamDegraded StreamCharacteristics Effects

• Channelization• Artificial substrate• Lack riparian

• Scouring / Erosion• Lower diversity• Higher water

temperature

Common Fishes of Common Fishes of Central TexasCentral Texas

Photo Credits – Tim Bonner Lab – Texas State University

Lepisosteus oculatus spotted gar 

Dorosoma petenense threadfin shad 

Cyprinella lutrensis red shiner  

Cyprinella venusta blacktail shiner  

Notropis chalybaeus ironcolor shiner  

Pimelphales vigilax bullhead minnow  

Ictiobus bubalus smallmouth buffalo  

Minytrema melanops spotted sucker  

Astyanax mexicanus Mexican tetra  

Astyanax mexicanus Mexican tetra  

Endangered Species Endangered Species of Edwards Aquifer of Edwards Aquifer

RegionRegion

Aquatic SpeciesAquatic Species• In addition to stream biota, the Edwards Aquifer

has over 40 species of highly adapted, aquatic, subterranean species

• These include amphipod crustaceans, gastropod snails, and interesting vertebrates like blind catfish. 

• Seven aquatic species are listed as endangered in the Edwards Aquifer system, and one is listed as threatened. 

Karst-dwelling Karst-dwelling speciesspecies

• In addition to the aquatic species that depend on Aquifer water itself, nine cave-dwelling invertebrates that live in the Aquifer's “karst formations” were listed by the US Fish & Wildlife Service as endangered in December 2000.  

• There are three beetles, one daddy long-legs, and five spiders. 

Endangered SpeciesEndangered Species

• The seven endangered species of the Edwards Aquifer system are:

• Fountain Darter (Etheostoma fonticola)• Texas Blind Salamander (Typhlomolge rathbuni)• San Marcos Gambusia (Gambusia georgei)• Texas Wild Rice (Zizania texana)• Comal Springs Riffle Beetle (Heterelmis comalensis)• Comal Springs Dryopid Beetle (Stygoparnus

comalensis)• Peck's Cave Amphipod (Stygobromus pecki)• The threatened species is:• San Marcos Salamander (Eurycea nana)

Fountain Darter (Etheostoma fonticola)

Texas Blind Salamander

San Marcos Gambusia (Gambusia georgei)

EXTINCT

Texas Blind Salamander

Comal Springs Dryopid Beetle (Stygoparnus comalensis)

Peck's Cave Amphipod (Stygobromus pecki)

Texas Wild Rice

Fish IdentificationFish Identification

American Fisheries Society. 2013. Common and Scientific Names of Fishes from the United States, Canada, and Mexico. Seventh Edition

Fish TaxonomyFish Taxonomy• Field Guides vs. Keys• Field guides may use ordering based on

alphabetic, similar shapes etc. • Keys and Scientific Guides use taxonomic

ordering of fishes.• Usually 1) jawless fish, 2) sharks and rays, 3)

primitive fish without fin spines and 4) fish with spines

Key to Species• Body stout, standard length only 2-3 times the depth. DIAMOND KILLIFISH Adinia xenica•Body slender, standard length more than 3 times the depth…………………………………………… 2

•Origin of dorsal fin over or slightly forward of anal fin origin…………………………………………... 3•Origin of dorsal fin distinctly behind anal fin origin. GOLDEN TOPMINNOW Fundulus chrysotus

Online KeysOnline Keys• http://www.fishesoftexas.org/key/• Hubbs, C., R. J. Edwards and G. P. Garrett. 2008.

An annotated checklist of the freshwater fishes of Texas, with keys to identification of species (Third Edition).

• http://www.texasacademyofscience.org/assets/GeneralFiles/hubbs_et_al_2008_checklist.pdf

• Dr. Bonner’s site: http://txstate.fishesoftexas.org/

Other OrganismsOther Organisms

Practice Makes Perfect!Practice Makes Perfect!

Questions?Questions?