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                    Eco-Meet 2019 Study Packet  This packet contains 7 factsheets about Carolina Bays and a small sample of the biodiversity associated with them.   1. Carolina Bays – 2 pages 2. Biodiversity – 2 pages 3. Pond Salamanders – 1 page 4. Marbled Salamander – 1 page 5. Giant Salamanders – 1 page 6. Eastern Cottonmouth – 2 pages 7. American Alligator – 2 pages    Science Georgia Standards of Excellence (https://www.georgiastandards.org/GeorgiaStandards/Documents/ScienceSeventhGradeGeorgiaStandards.pdf) S7L1. Obtain, evaluate, and communicate information to investigate the diversity of living organisms and how they can be compared scientifically. S7L4. Obtain, evaluate, and communicate information to examine the interdependence of organisms with one another and their environments.   South Carolina Academic Standards and Performance Indicators for Science (https://ed.sc.gov/scdoe/assets/file/agency/ccr/StandardsLearning/documents/South_Carolina_Academic_Standards_ and_Performance_Indicators_for_Science_2014.pdf) Standard 6.L.4: The student will demonstrate an understanding of how scientists classify organisms and how the structures, processes, behaviors, and adaptations of animals allow them to survive. Standard 7.EC.5: The student will demonstrate an understanding of how organisms interact with and respond to the biotic and abiotic components of their environments.

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Eco-Meet 2019

Study Packet

 

This packet contains 7 factsheets about Carolina Bays and a small sample of the biodiversity associated with them.

  

1. Carolina Bays – 2 pages 2. Biodiversity – 2 pages 3. Pond Salamanders – 1 page 4. Marbled Salamander – 1 page 5. Giant Salamanders – 1 page 6. Eastern Cottonmouth – 2 pages 7. American Alligator – 2 pages

   

Science Georgia Standards of Excellence (https://www.georgiastandards.org/Georgia‐Standards/Documents/Science‐Seventh‐Grade‐Georgia‐Standards.pdf) S7L1. Obtain, evaluate, and communicate information to investigate the diversity of living organisms and how they can be compared scientifically. S7L4. Obtain, evaluate, and communicate information to examine the interdependence of organisms with one another and their environments.

 

 

South Carolina Academic Standards and Performance Indicators for Science (https://ed.sc.gov/scdoe/assets/file/agency/ccr/Standards‐Learning/documents/South_Carolina_Academic_Standards_ and_Performance_Indicators_for_Science_2014.pdf) 

Standard 6.L.4: The student will demonstrate an understanding of how scientists classify organisms and how the structures, processes, behaviors, and adaptations of animals allow them to survive. Standard 7.EC.5: The student will demonstrate an understanding of how organisms interact with and respond to the biotic and abiotic components of their environments.

SRELWetlands Series

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Carolina BaysFact Sheet

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1. Flood control and water availability.2. Water quality — they purify water by processingnutrients, suspended materials and other pollutants.3. Erosion control.4. Wildlife habitat.5. Recreation.

DEFINITION

Carolina bays are isolatedwetlands in natural shallowdepressions that arelargely fed by rain andshallow groundwater.These bays have an ellipti-cal shape and generally anorthwest to southeastorientation. They are foundprimarily in Georgia andthe Carolinas, but rangefrom Florida to Delaware.As many as 300 Carolinabays exist on the SavannahRiver Site.

HABITAT DESCRIPTION

Carolina bays vary in sizefrom less than an acre tomany acres. Water levelsare normally lowest inautumn and highest inearly spring. Some Carolinabays are wet all year, whileothers fill with water, thendry up, depending on theseason. The amount oftime a typical bay holdswater can vary greatlyfrom year to year depend-ing upon rainfall. For ex-ample, during a 13-yearperiod, Rainbow Bay on theSavannah River Site heldwater only five days oneyear and about 280 daysanother year.

CAROLINA BAY WILDLIFE

Although many Carolinabays are temporary pondsthat hold water only partof the year, these wetlandshost a variety of wildlife,providing valuable habitatfor such animals as frogs,salamanders, turtles,snakes and alligators.Many birds, such as her-ons, egrets and migratorywaterfowl, live in Carolinabays. Also mammals, suchas deer, raccoons, skunksand opossums get foodand water from Carolinabays. In addition, micro-scopic organisms calledzooplankton live in Caro-lina bays. Salamanders andfrogs are among the mostabundant wildlife found inCarolina bays. As amphib-ians, these animals spendpart of their lives in the

water; as adults, they de-pend on Carolina bays asbreeding sites where theylay their eggs.

PLANT LIFE IN BAYS

Average water depth andsoil type have a large influ-ence on the types of plantsfound in and around Caro-lina bays. Many bays con-tain trees such as blackgum, sweet gum, magnolia,bald cypress and maple,and shrubs such as sumac,button bush, gallberry andred bay. Also common inCarolina bays are waterlilies, sedges and variousgrasses. On the SRS, 60percent of the rare andthreatened plant speciesare found in Carolina bays.

WETLAND FUNCTIONS

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of wetlands vary, some of the most important and mostcommon functions of wetlands are:

DID YOU KNOW?

Standard Time, on week-days. The phone number is1-800-832-7828.

MORE INFORMATION

For more information onCarolina bays, please callthe Savannah River EcologyLaboratory, Outreach (803)725-0156 or Public Rela-tions (803) 725-2473.

WETLANDS PROTECTION

The Environmental Protec-tion Agency offers a toll-free hotline that is respon-sive to public interest,questions and requests forinformation about thevalues and functions ofwetlands and options fortheir protection. Thehotline operates from 9a.m. to 5:30 p.m., Eastern

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BAY RESEARCH

Water levels vary greatlyfrom one Carolina bay tothe next and from one yearto the next even at a singlebay. Given the variations,ecologists at the SavannahRiver Ecology Laboratoryare studying how amphib-ians, plants and zooplank-ton (near-microscopicorganisms totally depen-dent on water to survive)adapt to such extremechange. Scientists aredeveloping a computer-based model that couldpredict the effects of cli-matic change — particu-larly global warming — onthe zooplankton and otheranimals and plants ofCarolina bays.

■ Researchers believe Carolina bays are 30,000 to 100,000 yearsold or older, yet scientists are not certain of their origins.

■ One theory of the origin of Carolina bays suggests that a me-teor hit Earth thousands of years ago, breaking into pieces thatmade dents as they skipped across the planet’s surface. Onelegend even has it that Carolina bays are dinosaur footprints (nottrue).

■ Some people consider Carolina bays to be annoying wet spots.Farmers commonly plowed through them and builders filled andpaved over them until federal wetlands regulations began pro-tecting them in the mid-1970s. Still, Carolina bays and otherwetlands continue to be lost to agriculture and commercial devel-opment.

■ More than 97 percent of the Carolina bays once found in SouthCarolina have been destroyed or severely altered. More protectedCarolina bays are found on the SRS than in the remainder ofSouth Carolina.

■ The United States has lost more than half of its original wet-land areas. More than 400,000 acres are lost annually.

This fact card is a publication of the University of Georgia’sSavannah River Ecology Laboratory. The Laboratory is operatedby the University of Georgia under a cooperative agreement withthe U.S. Department of Energy to conduct ecological research onthe Savannah River Site, a nuclear materials processing facilityon the Georgia/South Carolina border near Aiken, S.C.

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n

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n

n

Biodiversity may be defined simply as “the variety of life,” but it is muchmore than just the number of different kinds of organisms that occur inan area. Across all levels of biological organization, biodiversity includes:n genetic diversity—the variation in heritable

characteristics of each species,n species richness—the number of different

plant and animal species found in a particularplace,

n ecosystem diversity—the variety of habitatsor ecosystems across the landscape, and

n landscape diversity—the arrangement ofecosystems over a large land area.

Biodiversity also encompasses processes, such as biogeochemical cycles,biotic and abiotic responses to disturbances, and interactions amongliving organisms.

Biodiversity provides the basis for a functioning planet, buffering changeand conferring resilience over all levels of biological organization. Themany direct and indirect benefits of biodiversity include all the resourcesand processes required for human existence. For example, oxygenproduction, pollination of plants, global climate control, filtration andstorage of water by wetlands, and soil production and fertility are allbenefits of the biological diversity of the Earth. Additionally, there areintrinsic or aesthetic values to biodiversity that, to many people, are asvaluable as the more tangible benefits illustrated above. Because humantechnology will never be able to duplicate the myriad of processes thatoccur every day in nature, our future depends upon maintainingthe biodiversity of our planet.

Scientists and others have become increasingly alarmed at theaccelerating losses of biodiversity at all levels of biologicalorganization. Increases in human population coupled withcontinued conversion of lands for agriculture anddevelopment have resulted in increasing losses of geneticdiversity and species richness worldwide. Landscapes are beingaltered and fragmented and ecological processes are being affectedat a growing rate. Although the highest rate of biodiversity loss may

currently be in tropical regions, a 1996 assessment by The NatureConservancy estimated that one-third of U.S. species are at risk forextinction. In the U.S. the conversion of lands for agriculture anddevelopment has led to dramatic losses of grasslands, wetlands, and

old-growth forests. For example, less than 1% of theoriginal 500 million acres of grasslands that once

comprised North America’s Great Plains remainundisturbed by human activities; it is estimatedthat half the wetlands of the lower 48 states have

been converted for agriculture or other uses sinceColonial times; nearly all old-growth forest has been

eliminated from the eastern U.S.

The consequences of biodiversity losses are difficult to measureaccurately, but continuing losses ultimately compromise ecosystemintegrity—loss of biodiversity results in species, ecosystems, andlandscapes becoming less resilient. Although recent scientific studieshave shown that relatively few species serve as keystones, or criticallyimportant “drivers” of ecosystem dynamics in any particular ecosystem,it is impossible to know with certainty the absolute importance of anysingle species. Consequently, the lossof any one species may haveunforeseen effects. Further,as ecosystems change over

time, differentspecies mayfunction in new roles.

Biodiversity in the southeastern United States results from many factors,including the moderate climate and long growing season, topographythat ranges from dry ridges to wet bottomlands, a history of moderatedisturbances, including fire and windstorms, and the conjunction of thePiedmont, Sandhills, and Coastal Plain physiographic provinces. Thebiological diversity of the 310-square mile Savannah River Site (SRS) isunique within the Southeast. Only about 10% of the total land area ofthe SRS is developed or used for industrial purposes by the Departmentof Energy (DOE). The remainder of the Site is managed for timber,forest products, and wildlife by the U.S. Forest Service or is relativelyundisturbed, providing baseline Set-Aside or “control” areas and sitesfor long-term ecological research. These Set-Asides includerepresentative habitats of the SE U.S. and thus are important in enhancingthe biodiversity of the SRS. Upon establishment of the SRS in 1951, theAtomic Energy Commission recognized the need to inventory the naturalresources of the Site. Initial biological inventories were conducted byresearchers from The University of Georgia and the University of SouthCarolina. These early surveys led to the establishment of theSavannah River Ecology Laboratory (SREL) by The Universityof Georgia. For over 45 years, SREL scientists haveconducted ecological research on the SRS and havecontinued to document the biodiversity of the Site.

Studies by SREL scientists and others havedocumented that the biodiversity of the SRS maybe greater than that of any other comparably sizedarea of the Upper Coastal Plain. Seventy-nine species offreshwater fish live in SRS wetlands and virtually all of the morethan 50 species of mammals native to the Upper Coastal Plain are foundon the Site. Additionally, Upper Three Runs Creek, a blackwater streamthat flows through the SRS, has the highest reported biodiversity of aquaticmacroinvertebrates of any stream in the western hemisphere. The SRSalso is home to 42 species of amphibians and 59 species of reptiles,more than have been recorded from any other publicly owned land areain the United States, including the Everglades and Great Smoky Mountainnational parks. Federally threatened Americanalligators thrive on the SRS and other herpetofaunalspecies of state or federalconcern are also found here,including the Carolinagopher frog, tigersalamander, southernhognose snake, and

the pinesnake. Sitereservoirs, originally constructed tocool hot water effluent from nuclearreactors, now host thousands ofwaterfowl migrating between southernwintering areas and summer nestinggrounds. Winter surveys have documented that more of some species ofdiving ducks use SRS wetlands than all other inland freshwater habitatsin South Carolina. The SRS also provides nesting habitat for the federally

endangered red-cockaded woodpecker and foraging habitatfor the endangered wood stork, which nests in colonies

close to the Site. The genetic diversity of both of thesespecies has been well studied by SREL scientists.

The SRS hosts a diversity of plant communities–fromdry upland sandhills, through moderately moisthardwood slopes, to bottomland hardwoods and

cypress-tupelo swamps–which maintain natural nutrientcycles and control the movement of nutrients and water

through watersheds. More than 1,500 species or varieties ofvascular plants have been documented to occur on the SRS,

including the federally endangered smooth purple coneflower and 34plant species of conservation concern in South Carolina. This representsvery high species richness for an area of this size. In addition, habitatsthat are increasingly rare in the southeastern U.S. remain on the SRS,including pockets of sandhills-scrub oak and hundreds of Carolina baysand other temporary depressional wetlands. Long-term ecological studiesin these areas have confirmed their importance to maintenance of thebiodiversity of this region of the U.S.

Thus, although past management of the SRS focused on national securityneeds, it also resulted in the maintenance and enhancement of thebiological diversity of this vast tract of land. Maintaining the biodiversityof the SRS will require continued commitment and an acknowledgmentby stakeholders that conserving biological diversity is an important Sitemission. The SRS is faced with increasing threats from outside its borders,including development within the Upper Three Runs Creek watershed,continued agricultural and silvicultural conversion of natural habitats,and increasing industrial impacts to the Savannah River. Federal landssuch as the SRS offer unique opportunities to help maintain regionalbiodiversity in the face of such impacts. If the Savannah River Site is tocontinue as a center of high biological diversity in the Southeast, soundecological stewardship must be a top priority.

Many kinds (species) of amphibians require wetlands in which tolay eggs so their young (larvae) can grow and develop. In the

Aiken, SC area, there are four closely related species ofsalamanders whose individuals spend most of their lives in

forests, but migrate to small wetlands to lay eggs. These speciesare the marbled salamander, the mole salamander, the tiger

salamander, and the spotted salamander.

All four of these species have long life spans for such tinyanimals. Some spotted salamanders may live more than 20 years!

Studies at the Savannah River Ecology Lab have shown thatsome individuals of all of these species can live up to ten years in

the wild. Most of a salamander’s life is spent on land, usuallyunderground in shaded, moist, wooded habitats. When adults areready to breed, they migrate on rainy nights to seasonal wetlands.

These wetlands, because they dry occasionally, usually do nothave fish. This is very important from a salamander’s point of

view, because a fish can eat all its babies!

Pond Salamanders

This information is provided as a publicservice by the

Savannah River Ecology LaboratoryOutreach office

and theStudent Partners in Amphibian and

Reptile Conservation program(SPARC).

(Photos by David Scott)

Mole salamander

Spotted salamander

Tiger salamander

Spring

Summer Fall

Winter

▼▲

Marbled SalamanderAmbystoma opacum

This information is provided bySavannah River Ecology Laboratory Outreach

and SPARC.

Photos by David Scott

Femalesalamander

with eggs

Salamanderlarva

These beautiful salamanders are commonresidents of Carolina bays, river floodplains and otherwetlands in the Southeast. Marbled salamanders havestriking patterns of white, silver, or gray bands on adark ground color. Individuals are rarely more thanfive inches long from head to tail tip. They feed on smallinvertebrates including earthworms, a variety of insects, and evencentipedes. According to researcher David Scott from theSavannah River Ecology Lab (SREL), marbled salamandershave been known to live as long as ten years in the wild. Hehas found that marbled salamanders on the Savannah RiverSite lay an average of 80 to 120 eggs under logs or in clumps ofvegetation in wetland areas that are likely to flood in late autumn.When the fall and winter rains fill these wetlands and flood thesalamander nests, the eggs hatch and the larvae begin to grow anddevelop. After 3-6 months the larvae metamorphose into solid graysalamanders. As they mature they develop the bold silver pattern on their bodies. Males have alighter-colored pattern than females. Adult marbled salamanders live in the woods around thewetland and return to the water to breed and lay eggs.

Marbled salamanders, like many other amphibians, require wetlands to use as breedingsites and nearby forests to live in the rest of their lives. SREL researchers have collected andreleased as many as twelve thousand salamanders emerging from a single wetland in a 24-hrperiod. Some small wetlands (and surrounding forests) may be home to more than 100,000

salamanders! Many of our wetlands inthe East have been destroyed or heavilyaltered to the point where amphibianscannot survive in them. By studyingamphibians and the wetlands they livein, we will better understand the rolethat salamanders and other amphibiansplay in the ecology of our area.

This information is provided bySavannah River Ecology Laboratory Outreach and SPARC.

Photos by David Scott. Written by Tony Mills.Layout and Design by Lindy Nowak.

“Giant”Salamanders

When we think of salamanders, we usually think of small creatures that scurry away when we turn overrotten logs or other debris. Most people in the Southeast don’t realize that southeastern wetlands arehome to two groups of huge aquatic salamanders, sirens and amphiumas. Two species, the greater sirenand the two-toed amphiuma, may grow to massive sizes – the largest individuals reaching more thanthree feet in length. These amphibians spend most of their time hiding in weed-choked wetlands, slow-moving streams, and Carolina bays. People rarely encounter these two species, although fishermenoccasionally catch enormous black salamanders and assume that they are American eels (a species offish). Amphiumas, or “congo eels” as they are often called, can be common in many southeastern wetlands.Two-toed amphiumas occur on the Coastal Plain across much of the Southeast. These animals haveminiscule front and back legs with two toes on each foot. They feed on crayfish, aquatic invertebratesand other small animals that share their habitat. When wetlands dry up in extremely dry weather, thesesalamanders can be found deep underground in moist mud, where they remain until the wetlandrefills.Because sirens are similar in appearance and often occupy the same habitats as amphiumas, greatersirens are sometimes mistaken for two-toed amphiumas. Two key differences are that sirens only havefront legs, and they also have feathery external gills. In general, sirens are a bit shorter than amphiumas

and have a stockier body. Like amphiumas, sirens also feed on crayfishand other small animals. When wetland habitats dry, sirens gounderground, and they have the ability to form a cocoon around theirbodies to hold in moisture. This adaptation allows them to stay dormantin dry weather until the rains refill the wetlands. Sirens and amphiumasbelong to the extensive “hidden biodiversity “ of the Southeast. It ishard to believe that two such large animals are so infrequently seen.Although these two species are fairly common, very little is knownabout their natural history. More research is needed to determine whatrole they play in the ecosystem.

Sirens andAmphiumas

Myth and legend havemagnified the fury of this nativepit viper. Few Southerners arewithout tales of the snake alsoknown as the water moccasin.

The cottonmouth is a semiaquatic freshwater snake, closelyrelated to the terrestrial copperhead(A. contortrix).

Identification

Cottonmouths are oftendifficult for the lay person toidentify because the snakesexhibit so many variations incolor and pattern. They aregenerally dull-colored withbroad, thick heads. The dorsalpattern may appear in irregulardiamonds or irregular bands andthe color varies from darkbrownish-green to copper to almostblack. The background color variesfrom tan to olive. It is notuncommon to find solid-colored,unpatterned cotton-mouths. Agealso makes a difference incoloration; the juveniles may be avivid copper and old cottonmouthsmay be a gray-black.

Features

Cottonmouths have anopening located about half-waybetween the nostril and the eye,which is typical of pit vipers. This“pit” helps the snake detect warm-blooded prey. Cottonmouths haveelongated, triangular-shaped headswith broad, thick snouts. The eyesare located on the side of the headand the pupil is vertically elliptical,rather than round as are those of

nonpoisonous water snakes.The ridges above the eyes

protrude outward and nearly shieldthe eyes from above, which preventan observer above the snake fromseeing its eyes.

The Eastern Cottonmouth

The fangs of a cottonmouthare truly a wonder. They arelocated in the upper jaw and aretwice the length of the teeth andseparate from them.The fangs arehollow tubes through which venomcan be injected into prey. Theseweapons fold against the roof ofthe mouth when closed.Cottonmouths actually shed theirfangs periodically, so they alwayshave new ones developing.

Full-grown cottonmouths canapproach six feet in length butmany are smaller, usually three-to-four feet. The snakecharacteristically holds its head atan angle of 45 degrees and candetect movement for a distance ofat least fifty feet.

Habitat

Often found basking in thesun, the cottonmouth may also befound under boards or in the barkof rotting trees or stumps near thewater, especially in cold weather.While it has been thought that thecold keeps the cottonmouth

inactive, researchers at theUniversity of Georgia’sSavannah River EcologyLaboratory have observedvery active specimens all yearlong.

Defense

A cottonmouth that feelsthreatened will coil and open itswhitish mouth, exposing its fangsin a threatening display, but usuallywill not strike unless provoked.Another defensive move of thespecies is to flick their tails aboutto indicate their displeasure. Somewill also squirt musk from glandslocated on either side of the snake’stail.

Diet

Cottonmouths eat fish,amphibians, birds, rodents andother snakes and use their powerfulvenom to kill their prey. Thecottonmouth is not a picky eaterand will eat carrion withouthesitation. Moccasins are alsocannibalistic.

Most cottonmouths feedwhenever prey is available.Cottonmouths shed their skins inaccordance with how much theyeat, usually several times a year.

The Eastern Cottonmouth(Agkistrodon piscivorus)

According to research performed at SREL,cottonmouths did not bite when gently nudged bya booted foot but occasionally did bite whenstepped upon and frequently bit when picked up.But even when the snake does bite, it does notalways inject venom. The venom that is so deadlyto the water moccasin’s prey is usually reservedfor the hunt and not always released duringdefensive strikes against larger predators, such asman. This preserves the snake’s ability to huntand kill prey.

The cottonmouth looks, smells and soundsdangerous. Usually that is enough to avoidconfrontation and the pit viper will slither away,given the chance. Many bites occur when thedefensive pose is presumed to be a precursor tobiting and the person so threatened attempts toeither kill or approach the snake. In a pitchedbattle, the snake’s survival instinct will enable itto move quickly and it will not hesitate to bite.

If you see a cottonmouth, admire it from adistance. Do not attempt to pick it up. Do notprod it or otherwise annoy it. Do not attempt tokill it.

If you should be bitten, do not attempt firstaid yourself. The best thing to do is to get to anemergency room quickly. Often people do moreharm trying to treat a bite at the scene. See ourfact sheet on snake bite for more information.

This information is provided as a public service by the EnvironmentalOutreach and Education Division of The University of Georgia's SavannahRiver Ecology Laboratory located on the Savannah River Site near Aiken, S.C.

Reproduction

Reproduction occurs mainly,but not exclusively, in the spring.In many areas, cottonmouths donot breed every year, but onlyevery two or three years,depending on food availability.Litters vary in size and typicallyjuveniles display more aggressivebehavior than older snakes.

Enemies

The cottonmouth is notinvincible and has enemies allaround including such predatorsas owls, hawks, eagles snappingturtles and alligators. They arealso prone to parasites anddiseases, as well as other problemssuch as infections and ulcers.

Man, too, is an ememy.Ignorance makes many people killany snake, even if it is attemptingto flee. In a complex ecosystem,all creatures play important roles.

Avoiding Snakebite

American Alligator Fact SheetAmerican alligators inhabit

the southeastern United States.Once a federally listed endan-gered species, American alliga-tors have recovered in manyareas. The species is still feder-ally listed as threatened becauseit looks like the Americancrocodile, which is endangered.

HABITATAlthough they are primarily

freshwater animals, alligatorswill venture into brackish saltwater. Alliga-tors live inswampy areas,rivers,streams, lakesand ponds. Onthe SavannahRiver Site,alligatorsinhabit theSavannahRiver, itsswamp andtributaries, andPar Pond and other reservoirs onthe site.

BREEDINGAlligators are active year

around, but they are most activein the warmer months in Georgiaand South Carolina. With thestart of their breeding season inMay, males “bellow” to femalesand other males in the area. ByJune, pairs have mated, andfemales begin building moundnests out of marsh reeds or othervegetation.

Sometime during late Juneor early July, females lay be-

tween 20 and 60 eggs. The hard-shelled, white eggs are about 3inches long and resemble gooseeggs. The mother defends thenest against predators throughoutthe incubation period, about 65days. When the eggs are ready tohatch, the mother alligator digsinto the nest mound, opens anyeggs that have not hatched andcarries the young down to thewater. Females sometimesaggressively defend their youngfor more than a year.

FEEDINGAlligators are opportunistic

feeders; adults eat fish, turtles,wading birds, snakes, frogs andsmall mammals they find nearthe shoreline of their habitat.Young alligators feed on smallfish and aquatic insects, but inturn, they can be food for rac-coons, crabs, various types ofwading birds and even fish.

Mother alligators that arekilled or removed from the areacannot defend their nests oryoung, and the hatchlings oftenare doomed. If the young escape

predation and can find enoughfood, they may grow between 3and 8 inches in length yearly.When they reach lengths ofabout 6 feet, they are consideredadults.

RESEARCHScientists at the Savannah

River Ecology Laboratory havestudied American alligators onthe Savannah River Site formore than 25 years. They haverecorded population sizes,

distributionand trends;animal sizes,sexes, activityperiods, growthrates andreproductiveefforts; diet,nutrition andenergetics;responses tothermal efflu-ent fromreactors into

cooling reservoirs; uptake ofradionuclides; genetic patternsand the conservation of thespecies.

DID YOU KNOW?❏ The largest recorded Ameri-can alligator was 19 feet inlength.❏ Alligators and their relativesare the last of the living reptilesthat were closely related todinosaurs.❏ Alligators and crocodiles arerelated. But alligators haverounded snouts; most crocodilespecies have longer, pointed

This information is provided as a public service by The University of Georgia'sSavannah River Ecology Laboratory located on the Savannah River Site near Aiken, S.C.

4. Keep your petsand children awayfrom alligators.Large alligators do not recognizethe difference between domesticpets and wild food sources.When they are hungry, alligatorsact on their hunting instinct andmight attempt to feed on yourhouse pet if given the opportu-nity.

Or, a protective female maybelieve her young or eggs arethreatened and take defensiveaction. Be cautious when fishingin waters with alligators, as somewill not hestitate to grab ahooked fish or eat the fish on astringer.

5. Don’t swim inareas that areknown alligatorhabitats.Always be careful around water.Splashing can attractalligators that think a preyanimal is injured. They may acton instinct and attack.

Advice to Remember“Alligators are fascinating creatures and should by all means be enjoyed as part of the natural

beauty of our region. But please remember that they are wild animals and should be respected as such.Once they become too familiar with people, they lose their fear of humans, necessitating their removalfrom the area for the safety of everyone concerned. A few precautions on our part can help both humans and alligators co-exist safely.”

--Dr. J. Whitfield GibbonsSREL senior ecologist

1. Don’t feed the alligators.This is a most important rule!Providing food for these wildanimals not only makes thembolder and encourages them to

How You Can SafelyObserve Alligators

seek out people, it also alterstheir natural diet in an unhealthyway.

2. Keep yourdistance.Although they may look slowand awkward, these animals areextremely powerful and canmove with a startling burst ofspeed on land over short dis-tances. A safe distance from anadult alligator is about 60 feet.

3. Never disturb nestsor small alligators.Some female alligators protecttheir young and may becomeaggressive if provoked. A babyalligator should never be cap-tured, even if the mother is notvisible. She may be watchingyou and decide to take action toprotect her baby.

snouts. Also, crocodiles occuronly in tropical and subtropicalareas (only south Florida in theUnited States). Alligators, on theother hand, live in somewhatcolder climates.❏ Alligators have a stronghoming instinct and sometimeswill protect their “territory” fromother alligators.

RANGEOn the Atlantic Coast, they

occur from Florida to coastalNorth Carolina. Alligators arealso found in the Upper CoastalPlain, which includes the CentralSavannah River Area of Georgiaand South Carolina. In SouthCarolina, alligators have beenrecorded to reach lengths ofmore than 13 feet.