Endangered Species

Texas Endangered Species Program Outline

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Objective: To· illustrate issues of endaQgerment utilizing ANSC animals, resources and the Zilker Nature Preserve. .

Station I: How do animals ~ecome endangered? A. Discuss and clarify terms: threatened, endangered, extincl(See background information) B. Discuss natural extinction versus extinction caused by humans. C. Discuss factors causing endangerment and show animals andlor props:

1. .Habitat Loss: Accounts for over 70% of endangered or threatened animals. Human encroachment means loss of homes, food and water for animals:· Human habitation also leads to death due to traffic. People are also often frightened by wild animals and feel they must ldll the animals if they live near people. (Show Gulf Coast Toad and relate Houston Toad story fro~ pac~t).

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2. Over-collection: Collection of wild animals for pets is unhealthy for a species because a single collected. animal cannot reproduce. Overcollection has played a major role iit the endangerment of the Texas tortoise ( it only lays one egg every two years) and the already troubled Texas homed lizard. The Mexican red-legged tarantula is threatened due to over-collection. (Show tarantula). 3. Pollution: Tell Barton Springs salamander story (Splash training). (Show tiger salamander).

4. Vulnerability: Bats are very vulnerable because many live in large colonies which can be destroyed all at once by pollution, structural damage, or human interference. (Show bat).

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5. Over-huntinglCompetition: The mountain lion and American alligator were both hunted on a "no bag limit" "no season" basis. The American alligator was placed on the Endangered Species list many years ago and has now recovered to the point that it is no longer endangered. (Show skull) ~e mountain lions in Texas have historically been hunted and ldlled by fanners and ranchers who see them as a threat to their livestock. Viewing animals as a threat is a form of competition. The mountain lion is now classified as ''threatened'' in Texas. Humans also view some animals as "competition" for natural resources. The American bison was considered by Texas settlers to compete wi$ -domestic livestock for food. The settlers therefore participated in the full-scale slaughter of these animals, which eventually led to their extinction in Texas.

Texas Endangered

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page 2 6. Multiple Factors: Kemps Ridley turtles are endangered because: 1.) harvest of eggs and meat as "delicacy" 2.) trawl nets 3.) pollution in water--trash, oil 4.) other factors: entanglement in nets, collision with boats, explosives, entrapment in coastal power

plant intake pipes (Show sea turtle shell. Additional turtle info 4t

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7. Poaching:· illegal hunting of animals is called "poaching". Some endangered animals, such as elephants, are hunted and killed for body parts. It is illegal to bring items made from endangered animals into this country. Customs officials at.airports and other points of entry check to make sure persons do not bring such illegal items acrOS$ our borders. If such items are found they are confiscated and those attempting to bring them in. are fined. Items in our Endangered Species box were confiscated by the Fish and Wildlife Department and were stored in a warehoUse in San Antonio. (Show some items from box.)

. Station IT:

How We Can Help 1.. Captive breeding programs: (See article ''Born to be Wild" in information packet) You may want to show pictures and discuss peregrine falcon and California cond9r efforts. Tell ferret story (see packet) and show ferret with tube.

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2. Legal protection: Discuss protection of Birds of Prey and show owl.

3. Preserves: You may want to show pictures of ocelot and jaguanmdi (see packet for info) and discuss Wildlife Corridor. Show pictures · and explain plight of black-capped vireo and golden-cheeked warbler.(see packet) Discuss the use of preserves in Austin to accommodate these endangered animals.

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Zilker Nature Preserve and Dilemmas

1. Hike to the preserve entrance and introduce the preserve.· Show the ashe Juniper and discuss its importance to the golden-cheeked warbler. .

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2. Hike to creekbed. Discuss the Edwards Aquifer and discuss the

dilemma it presents. Divide the class into groups. Give' each group a dilemma card and encourage brain-storming. Let each group report to the class.

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3. What can we eac~ do ~very day to l,1elp endangered species? Recycle, walk, ride bus, nde bikes, etc. . 4. Why should we heip endangered species? (See article in packet) . Tell starfish story (see below). Show starfISh.

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Texas Endan2ered page-three Starfish Story .. S tartish eat mollusks and are therefore key to maintaining mollusk diversity by keepine different mollusk populations in check. If starfish are removed from the area, one or two species of mollusks (usually type of mussel) take· over and out-compete others. H the habitat originally contained ten mollusk species, without the starfish only one or two species survive. nus is hannful because different mollusk species keep other species in check. . Mollusks are helpful because they scrape algae. They are filter-feeders--they pull \vater through their gills. This filtering cleans the water. The fewer the mollusk species, the dinier the water. Without the starfish to contribute to species diversity, mollusk species which are not as adept at filtering water may out-compete more competent fIltering species.

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See starfish article in packet!

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T - Western prairie fringed orchid (Platanthera praeclara) ~

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Texas-73 species ~ Animals--46 species

E - Ampbipod, Peck's cave (Stygobromus (=Stygonectes) pecki) ~ E - Bat, Mexican long-nosed (Leptonycteris nivalis) ~ T - Bear, Louisiana black (Ursus americanus luteolus) ~ E - Beetle, Coffin Cave mold (Batrisodes texanus) E - Beetle, Coma! Springs riftle (Heterelmis comalensis) ~ E - Beetle, Cornal Springs dryopid (Stygopamus comalensis) ~ E _.. Beetle, Kretschmarr Cave mold (Texamaurops reddellr) E - Beetle, Tooth Cave ground (Rhadine persephone) E -- Crane, whooping (Grus americana) ~ E - Curlew, Eskimo (Numenius borealis) ~ E - Darter, fountain (Etheostoma fonticola) ~ T - Eagle, bald (Haliaeetus leucocephalus) ~ E - Falcon, American peregrine (Falco peregrinus anatum) ~ E -- Falcon, northern aplomado (Falco femoralis septentrionalis) ~ E -- Flycatcher, Southwestern willow (Empidonax traillii extimus) ~ E - Gambusia, Big Bend (Gambusia gaigel) ~ E - Gambusia, Clear Creek (Gambusia heterochir) ~ E - Gambusia, Pecos (Gambusia nobilis) ~ . E - Gambusia, San Marcos (Gambusia georger) ~ E - Harvestman, Bee Creek Cave (Texella reddelll) Harvestman, Bone Cave (Texella reyeSl) E - Jaguar (Panthera onca) ~ E - Jaguanmdi, Gulf Coast (Herpailurus (=Felis) yagouaroundi cacomitll) ~ E - Manatee, West Indian (Trichechus manatus) ~ E -:- :Minnow, Rio Grande silvery (Hybognathus amarus) ~ E - Ocelot (Leopardus (=Felis) pardalis) ~ T -- Owl, Mexican spotted (Strix occidentalis lucida) ~ E - Pelicat4 brown (pelecanus occidentalis) ~ T - Plover, piping (Charadrius melodus) ~ E - Prairie-chicken, Attwater's greater (Tympanuchus cupido attwateri) ~ E -Pseudoscorpion, Tooth Cave (Tartarocreagris (=Microcreagris) terona) ~ E - Pupfish, Comanche Springs (Cyprinodon elegans) ~ E - Pupfish, Leon Springs (Cyprinodon bovinus) ~ E -- Salamander, Barton Springs (Eurycea sosorum) ~ T - Salamander, San Marcos (Eurycea nona) ~ E - Salamander, Texas blind (Typhlomolge rathbuni) ~ E - Sea turtle, Kemp's (=At1antic) ridley (Lepidochelys kempii) ~ T - Sea turtle, loggerhead (Caretta caretta) ~ . T - Shiner, Arkansas River (native pop. only) (Notropis girardI) ~ ~ - Snake, Concho water (Nerodia paucimaculata) ~ -' - Spider, Tooth Cave (Nealeptoneta (=Leptoneta) myopica) ~ F . Tern, least (Sterna antillarum) ~ ~UToad, Houston (Bufo houstonensis) ~

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E - Vireo, black-capped (Vireo atricapillus)': E - Warbler, golden-cheeked (Dendroica chrysoparia) * E - Woodpecker, red-cockaded (Picoides borealis) ~ Plants-27 species

E - Large-fruited sand-verbena (Abronia macrocarpa) *. E - South Texas ambrosia (Ambrosia cheiranthijolia) ~ E -- Tobusch fishhook cactus (Ancistrocactus tobuschii) * E -- St~r cactus (Astrophytum asterias) ~ E - Texas ayenia (Ayenia limitaris) I\: E - Texas poppy-mallow (Callirhoe scabriuscula) E -- Nellie cory cactus (Coryphantha (=Escobaria) minima) *. T -- Bunched cory cactus (Coryphantha ramillosa):: E -- Sneed pincushion cactus (Coryphantha sneedii var. sneedii) ~ E -- Terlingua Creek cats-eye (Cryptantha crassipes) . T -- Chisos Mountain hedgehog cactus (Echinocereus chisoensis var. chisoellsis).~ E -- Lloyd's hedgehog cactus (Echinocereus lloyd;;) ~ E -- Black lace cactus (Echinocereus reichenbachii (=melanocentrus) var. albertil) E -- Davis' green pitaya (Echinocereus viridiflorus var. dal'isii) .: T -- Lloyd's Mariposa cactus (Echinomastus (=Sclerocactus) mariposensis) E -- 10hnston's frankenia (Frankeniajohnstonii) E -- Slender rush-pea (Hoffmannseggia tenella) *. E - Texas prairie dawn-flower (=Texas bitterweed) (Hymenoxys texana) E - White hladderpod (Lesquerella pallida) E -- Walker's manioc (Manihot walkerae) E -- Texas trailing phlox (Phlox nivalis ssp. texensis) E -- Little Aguja pondweed (Potamogeton clystocarpus) T -- Hinckley's oak (Quercus hinckley;) ~ . E -- Navasota ladies'-tresses (Spiranthes parksii) ~ E -- Texas snowbells (Styrax texanus) ~ E - Ashy dogweed (Thymophylla tephroleuca) E -- Texas wild-rice (Zizania texana) Region 2 Listed Species by State, Endangered Species; U.S. Fish &, Wildlife Service

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u.s. FISH AND WILDUFE SERVICE DIVISION OF ENDANGERED SPECIES ==:=============== [Return to the State List by Region page.] • • • • • • • • • • • • • • • • • • • • • • • • • • 0 • • • • 00 • • • • 0 0 • • • • • • • • • • 0 • • • • 0 • • 0 • • 000.

[Click the A symbol anywhere below to return here.]

Region' 2 Listed Species Under Fish and Wildlife Semce Jurisdiction By State as of 04/31199

To locate additional regulatory information about a listed species, find and click its scientific name in the Remonal Index File. Figures or other information may also be available, indicated by a clickable asterisk (*) after the name below, in the Index FJ1es, or by locating the species with a search. You are also invited to visit the Regional Home Page. The listing status of each species in each State, T = threatened or E = endangered is indicated before its name in this list. TABLE OF CONTENTS

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Amazing Animals Dinosaurs & Descendants

Disappearing Acts

Dodo The Dodo is a lesson in extinction. First sighted around 1600 on Mauritius, an island in the Indian Ocean, the Dodo was extinct less than eighty years later.

Fifty Treasures

Under the Sea Up in tbeAir World Cultures

Expedition Guide QOJ,lQ

/3arosaurus UQ~aut:.Em.hryQ

.:lana Island Diorama Peregrine Falcon Diorruna ,ea.S_S~M~t.J~igeol1S Ostrig.bJ)ior&m~

Thus while the skeleton (above) on view in the Museum is real, the model (below) is not, as there are no complete Dodo specimens. Some of the birds may have been eaten by the Dutch sailors who discovered them. However, the primary causes of their extinction were the destruction of the forest (which cut off the Dodo's food supply), and the animals that the sailors brought with them, including cats, rats, and pigs, which destroyed Dodo nests.

Dinosaur Mummy 7}rq1Jl1.0~.Qur1A§

Gl~Jt RQ.s.~ .Irc:t<;!kw~y

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The Dodo's stubby wings and heavy, ungainly body tell us that the bird was flightless. Moreover, its breastbone is too small to support the huge pectoral muscles a bird this size would. need to fly. Yet scientists believe that the Dodo evolved .from a bird capable of flight into a flightless one. When an ancestor of the Dodo landed on Mauritius, it found a habitat with plenty of food and no predators. It therefore did not need to fly, and, as flying takes a great deal of energy ~ it was more efficient for the bird to remain on the ground. Eventually, the flightless Dodo evolved.

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.:.;:. ·:?otl1~r:jIrStifu~roris·:a.r01itfd:theworld continue to stUdy. and document the impact of human activities on the environment. It ~~. hop~4that the lessOl(of the Dodo can help prevent s~ar extinctions, and aid us' in preserving the diversity of life on earth.

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European ferrets prefer to eat wild hares which in European countries live underground. They have been domesticated for several centuries. In some European countries "ferreting" remains a popular way to hunt. The ferret is sent down into holes where hares are thought to be. Nets set up at the other openings and the hare is caught in these as it exits trying to escape the ferret. European ferrets have also helped their owners by ridding the house and barn of rats and mice.

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The primary food source of the black-footed ferret has been prairie dogs. Like its cousin the European ferret, the black-footed ferret is unmatched for catching burrow-dwelling prey. Unfortunately the prairie dog and its habitat, the prairie dog "town", are now greatly reduced in number and area. It proved to be a great conflict of interest between the prairie dogs "squatters rights" and the cattle rancher who greatly 'disdained shooting prize cattle and horses that stepped into this small rodent's hole and broke their legs. Ranchers also perceived the prairie dogs as competitors for the grass that their cattle grazed. It has been no surprise that the ranchers have gone to great expense to rid themselves of this "good-for-nothing rodent." Using poison, traps, gas, and ammunition, the ranchers with the help of the United states government have been very successful in their battle against these animals. The use of one of the weapons, a deadly chemical called Compound 1080 has been used to control the prairie dogs as well as coyotes, wolves, bobcats, and other predatory animals and birds. One of the most unfortunate results of Compound 1080 has been the loss of black-footed ferrets. Becaus~ the ferrets are· directly linked to the prairie dogs, the future of the black-footed ferret is most uncertain. Black-footed ferrets were once found roughly throughout the northwestern third of Texas in the same areas where black-tailed prairie dogs prospered. The last known Texas sighting was in Bailey County in 1963, but they are believed to no longer live in Texas. In fact, the U.s. Fish and Wildlife Department nearly declared them an extinct species in the u.s. in 1980. However a small population of ferrets was confirmed in Wyoming. Now both federal and private landowners are cooperating to protect these very rare mammals. ' The story of the plight of the black-footed ferret is a lesson for us all. It is the story of yet one more animal that has been brought to the brink of extinction by people and their sometimes short-sighted economic objectives. If the natural world had warning lights as do our automobiles we would surely see a number of red lights on our instrument panel and one of them would have to be the black-footed ferret.

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The Passenger Pigeon

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n all probability, the Passenger Pigeon was once the most abundant bird on the planet. Accounts of its numbers sound like c:omething out of Alfre.d Hitchcock's The Birds and strain our credulity today. Alexander Wilson, the-father of scientific (-lithology in America, estimated that. one flock consisted of two billion·birds. Wilson's rival, John James Audubon, watched a .:lck pass overhead for three days and estimated that at times more than 300 million pigeons flew by him each hour. Elongated nesting colonies several miles wide could reach a length of forty miles. In these colonies, droppings were thick enough to kill the forest understory. passenger Pigeons were denizens of the once great deciduous forests of the eastern United States. The birds provided an easily harvested resource for native Americans and early settlers. To obtain dinner in the nesting season one needed only to wander into a colony and pluck some of the fat squabs that had fallen or been knocked from their nests. Audubon wrote in his classic Birds of America, "The pigeons were picked up and piled in heaps, until each [hunter] had as many as he could possibly dispose of, when the hogs were let loose to feed on the remainder."

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Old magazine Illustration of hunters shooting Passenger Pigeons. Note the density of the fiight.(From copy in Schorger, 1955.)

Market hunters prospered, devising a wide variety of techniques for slaughtering the pigeons and collecting their succulent squabs. Adults were baited with alcohol-soaked grain (which made them drunk and easy to catch), and suffocated by fires of grass or sulfur that were lit below their nests. To attract their brethren, captive pigeons, their eyes sewn shut, were set up as decoys on small perches called stools (which is the origin of the term stool pigeon for one who betrays colleagues). Squabs were knocked from nests with long poles, trees were chopped down or were set on fire to make the squabs jump from nests. Disruption of the colonies was so severe that wholesale nest abandonment was common and breeding success much reduced. So successful were the market hunters that pigeons became cheap enough for use as live targets in shooting galleries. Laws intended to protect the pigeons did not help. In 1886 an editor's note in Forest and Stream said: When the birds appear aI/ the male inhabitants of the neighborhood leave their customary occupations as farmers, bark-peelers, oil-scouts, wildcatters, and tavern loafers, and join in the work of capturing and marketing the game. The Pennsylvania law very plainly forbids the destruction of the pigeons on their nesting grounds, but no one pays any attention to the Jaw, and . the nesting birds have been killed by thousands and tens of thousands. As railroads penetrated the upper Middle West after the Civil War, many millions of pigeons were shipped to cities along the Atlantic seaboard, since, by then, clearing of oak and beech forests and hunting had already exterminated the birds on the East Coast. Extinction of the Passenger Pigeon came with stunning rapidity. Michigan was its last stronghold; about three million birds were shipped east from there by a single hunter in 1878. Eleven years later, 1889, the species was extinct in that state. Although small groups of pigeons were held in various places in captivity, efforts to maintain those flocks failed. The last known individual of the species, a female named Martha, died in 1914 in the Cincinnati Zoo and is now on display in the U.S. Na~onal Museum of Natural History. Vourse, market hunting ended as soon as harvesting the birds was no longer economically profitable. That point was r~ached when tens of thousands of the birds still flew within large stretches of suitable habitat. Much of that habitat still exists today, although many of the largest nut-producing trees that were common in the heyday of the pigeon were logged. Why, then, did the birds go extinct? No one knows for sure, but it appears that to survive they needed to nest in vast colonies. Perhaps this permitted them to "swamp" predators with their enormous numbers, so that the relatively few predators in the

area of a roost were unable to make a significant dent in the huge breeding colonies. And since these colonies dispersed as soon as breeding was over, predators were prevented from building up their populations on the basis of such an ephemeral resource. In any case, the fate of the Passenger Pigeon illustrates a very important principle of conservation biology: it is not always necessary to kill the last pair of a species to force it to extinction. Sad to say, the lesson of the Passenger Pigeon has not been learned. At.the present time the White-crowned Pigeon is threatened by the horrendous slaughter of nesting birds on its Caribbean breeding grounds.

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SEE: Conservation of the California Condor; Island Biogeography; The Decline of Eastern Songbirds. Copyright ® 1988 by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye.

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