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Jason Naber and Mike Majeski

This Months Featured Article

The American Alligator By Bill Moss

A UGUST 2004

V OLUME 24

WEB VERSION

INFORMATION

Field Experiences From Recent Massasauga and Wood Turtle Field Survey Projects.

TO RESPECT PRIVACY CONCERNS

August’s Speakers:

EDITED/REMOVED

THE NEWSLETTER OF THE

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Board of Directors President Randy Blasus

Vice President Tony Gamble

Recording Secretary Barb Buzicky

Membership Secretary Nancy Haig

Treasurer Liz Bosman

Newsletter Editor Bill Moss

Members at Large Heather Clayton Nancy Hakomaki Mike Bush Jodi L. Aherns

Committees Adoption Sarah Richard

Bell Museum of Natural History, 10 Church Street Southeast, Minneapolis Minnesota 55455

The Minnesota S o c i

Herpetological e t y

MHS Webpage: http://www.mnher psoc.org MHS Group Email: http://www.groups.yahoo.com/group/mnherpsoc MHS Voice Mail: 612.624.7065 The Purpose of the Minnesota Herpetological Society is to: • Further the education of the membership and the general public in care and captive propagation of reptiles and amphibians; • Educate the members and the general public in the ecological role of reptiles and amphibians; • Promote the study and conservation of reptiles and amphibians. The Minnesota Herpetological Society is a non-profit, tax-exempt organization. Membership is open to all individuals with an interest in amphibians and reptiles. The Minnesota Herpetological Society Newsletter is published monthly to provide its members with information concerning the society’s activities and a media for exchanging information, opinions and resources. General Meetings are held at Borlaug Hall, Room 335 on the St. Paul Campus of the University of Minnesota, on the first Friday of each month (unless there is a holiday conflict). The meeting starts at 7:00pm and lasts about three hours. Please check the MHS Voice mail for changes in schedules or cancellations.

Education Jan Larson

Library Beth Girard

Webmaster Anke Reinders theMHSwebmaster@yahoo.com

Herp Assistance Amphibians Greg Kvanbek John Meltzer

Submissions to the Newsletter Ads or Notices must be submitted no later than the night of the General Meeting to be included in the next issue. Longer articles will be printed as time and space allows and should be in electronic file format if possible. See inside back cover for ad rates. Submissions may be sent to: -orThe Minnesota Herpetological Society Bill Moss Attn: Newsletter Editor 75 Geranium Ave East Bell museum of Natural History Saint Paul, MN 55117 10 Church St. SE. -orMinneapolis, MN 55455.0104 mngatorguy@msn.com

Chameleons Vern & Laurie Grassel Crocodilians Jeff Lang Bill Moss Lizards Nancy Haig Large Boas, Pythons Tina Cisewski Other Snakes Jeff Leclere John Meltzer Aquatic Turtles John Levell John Moriarty Terrestrial Turtles Fred Bosman John Levell Copyright 2004, Minnesota Herpetological Society. Except where noted, contents may be reproduced for nonprofit, non-commercial use only. All material must be reproduced without change. Proper credit will be given including the author/photographer and the MHS Newsletter citing: volume, number and date.


The Newsletter of the Minnesota Herpetological Society

The Vice-presidents report By Tony Gamble

August General Meeting Meeting: Friday, August 6th, 2004, 7 PM Program: Herpetological Surveys: Two contract herpetological surveyors share their field experiences from recent massasauga and wood turtle projects. Guest speakers: Jason Naber and Mike Majeski, of Emmons and Olivier Resources, Inc. Massasaugas (Sistrurus catenatus catenatus), Minnesota's "other" rattlesnake, are currently state listed as "endangered". While historical records document the occurrence of massasaugas in the extreme southeastern portion of the state, none have been found here in decades. Known massasausga populations exist east of the Mississippi River in Wisconsin but historical records can not confirm viable populations in Minnesota. Jason Naber and Mike Majeski established a baseline effort for which future survey efforts may be conducted to help determine the official status of the massasauga in Minnesota. They surveyed suitable snake habitat in Houston, Winona, and Wabasha counties in 2002 and 2003. Survey methods focused on searching meadows and forest edges along the Mississippi River and its major tribCover photo: American Alligator by Bill Moss

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utaries. Special attention was given to brush piles and basking sites that, in Wisconsin, have been found to be frequently used by massasaugas. While Jason and Mike did not find any massasaugas in Minnesota they did identify suitable habitat which can help future surveyors. Jason Naber and Mike Majeski both work for Emmons and Olivier Resources, Inc, a private environmental consulting firm in the Twin Cities. They have recently conducted herpetological surveys for the Minnesota & Wisconsin DNR. Their work included a two-year field survey for massasaugas in Minnesota, radio telemetry of massasaugas in Wisconsin, and wood turtle surveys in Minnesota. They will discuss methodologies used in each project and share photos of critters encountered. This will be an interesting talk about two rare Minnesota reptiles. Don't miss it! September - TBA

Number 8

Raffle Donors - July A special thanks to he following people for donating to the MHS raffle Marylin Blasus Vern and Laurie Grassel “Stuffed” snake and lizard Brian and Heather Ingbretson “Hatching snakes”, Biomite and Nomite

Critter of the Month The following people brought animals to the July meeting: Beth Girard Diploda John Moriarty Wood Turtles Tony Gamble Stink Pot Turtle

October - TBA

Plus..... In addition to our regular speakers, MHS members Nancy Hakomaki and Bill Moss will give a special slide presentation about the MHS experiance at the Minnesota Renaissance Festival. The presentation will introduce the audience to what the MHS is doing at the faire and some do’s and don’t of proper costuming. Page 3


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News, Notes & Announcements MHS Elections by Barb Buzicky Hey, it’s that time again to think about MHS Board elections!! The Annual Meeting will be held in November, so there isn’t much time left. If you want to take an active part in the MHS Board, now is the time to step forward. Further, I am looking for volunteers to join me on the Election Committee to help find candidates for Board positions. Please e-mail me at (email address removed) if you are interested in working on this committee. There are some questions that people ask about being an elected board member, and I have summarized the most pertinent information. If you have any other questions that weren’t answered here, please feel free to e-mail me!! In order to run for a board position, you have to be a current active member along with being 18 years or older when you take office in January. Members must be present to vote as there are no absentee ballots issued. Only one person can occupy a board position as there is no co-sharing positions. Board Members may delegate any job function(s), except voting, to another member, but the Board Member is ultimately responsible for completion of all duties. Board Member’s duties include serving on and chairing committees, working on special projects and assignments for the Board, and responding to correspondence as required. Board Members are also required to attend Board Meetings, fill in for any missing Board Member at meetings and monitor the voicemail messaging service on their assigned month. All Board Members must abide by the Bylaws and Policies of MHS. Now Page 4

with all that out of the way, here is a description of each position. I will also have extra copies available at the October meeting for review. Please feel free to solicit information from any current Board Member if you have any questions. President The President chairs the monthly general and board meetings of MHS, appoints and maintains contact with committee chairs and delegates tasks to other Board Members. The President also makes a calendar of meetings, picks up and distributes the society’s mail, and acts as a public spokesperson for the Society. The President coordinates the common vision and goals of MHS, promoting its growth and sustainability, and upholds the Bylaws. Vice President The Vice President is responsible for coordinating and introducing the speakers for the monthly Meetings, and introducing the Critter of the Month presenters. Vice presidential duties also include assisting the President, performing the President’s duties in case of absence, notifying the Newsletter editor of upcoming speakers, sending notices of monthly meetings to local newspapers, and changing the voicemail message monthly. Treasurer The Treasurer is required to maintain and balance the MHS financial accounts and keep complete records of all financial transactions. This includes collection and depositing all income in a timely manner, producing both a monthly and an annual

financial statement for the newsletter, and supplying the Board with a monthly financial activity report. The Treasurer also participates in the complete yearly audit and budget. Membership Secretary The Membership Secretary collects, maintains, and updates the membership database. The Membership Secretary is also responsible for supplying a monthly summary of membership activities, maintains a file of prior newsletters, and responding to all information and membership inquiries. The Membership Secretary also maintains the name tag box. Recording Secretary The Recording Secretary records the minutes of the monthly board and general meetings and provides summaries to the newsletter Editor. The Recording Secretary maintains: the minutes of the board meetings, a complete archive of past newsletters, and a listing of the inventory of MHS supplies, fixures, and goods. Other duties include chairing the Election Committee and providing an annual summary of any unresolved action items. Newsletter Editor The Newsletter Editor edits submissions, enters monthly business, and prepares the MHS newsletter for printing. The Editor also solicits articles, items of interest, and advertising. The Editor is responsible for the appearance of the newsletter. Members-At-Large (4 positions) The Members-At-Large participate in the decision making process, volunteer for projects or committees. The Members-At-Large perform other duties as assigned by the President.


The Newsletter of the Minnesota Herpetological Society

July Speaker Review by Barbara Buzicky, MHS Recording Secretary

Guest Speaker: John Moriarty Program:“Turtles and Turtle Watching for the North Central States” This month’s speaker was John Moriarty, and he has been a long time member of the Minnesota Herpetological Society. He has held many offices for the Society, and he works a lot with turtles. He is writing a book entitled the same as his talk tonight “Turtles and Turtle Watching for the North Central States.” He says it is a field guide book compact and smaller in size for easy handling while field herping. There will be many photos that will help “new herpers” recognize the different turtle species. There will also be habitat information and tips on how to observe these animals in the field. Turtles can also be found by following their tracks over the dirt and sand. Or, when they shed their scoots, these leftovers help to locate where they may be basking. Many members of the MHS have made contributions to this book. The printer has been chosen, so it’s a matter of getting them printed and circulated. There will be copies available at the MHS General Meetings when they are available for sale. There are three major families of turtles native to Minnesota which are: Family TrionychidaeSoftshells, Family ChelydridaeSnapping Turtles, and Family Emydidae- Pond and River Turtles. The softshells located here are the

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smooth softshell (Apalone mutica) and the spiny softshell (Apalone spinifera). The smooth softshell is a medium sized turtle that has a very smooth surface, and they look kind of flattened like a pancake. The carapace feels like leather and is very tough and pliable. They have webbed feet, and their snout is long and round kind of like an ant eater. They can be found in large rivers, and they prefer very sandy and muddy areas. They avoid dense vegetation and rocky bottoms. They hibernate over the winter burrowed in the mud on the river bottoms so they avoid the freezing temperatures. The spiny softshells are larger with a pancake shaped body with a pointed snout. The carapace has many spines or nubs protruding from the edges. The spiny softshell is a river turtle, but it can also be found in large lakes. They also require mud and sand on the river bottoms especially sandbars and beaches. They also avoid vegetation and rocky bottoms. They hibernate in the same manner as the smooth softshell. The snapping turtle (Chelydra serpentina) is Minnesota’s largest turtle named of course for its behavior and attitude. It has a massive carapace and large head with very strong jaws. Snapping turtles use their claws effectively for mobility. Snapping turtles live in many fresh bodies of water including ponds, lakes, marshes, rivers, creeks, and backwater sloughs. These turtles like mud bottoms and plentiful vegetation where they gather. They also hibernate over the winter by burying themselves in mud and plant vegetation to keep from freezing.

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In the last grouping, Family Emydidae, there are many species in Minnesota. The first and most common is the painted turtle (Chrysemys picta). The name fits the turtle as it is the most colorful of all the turtles in this grouping. They are small to medium sized, and the design on their plastrons and scoots range from very bright orange and beige to a little less bright shade of red. They also have a great shade of green on their skins along with bright yellow stripes. They all have different patterns on the carapace underneath which make them very attractive. Male painted turtles are smaller than their female counterparts, and they have a large very thick tail and elongated fore claws. These turtles can be found in bodies of water such as ponds, lakes, marshes, sloughs, and creeks. They like soft sandy or muddy bottoms, lots of vegetation, and different types of places for basking like old tree logs and large rocks. The wood turtle (Clemmys insculpta) is also an attractive turtle with different colors instead of oranges, they have lots of deep yellow or tan shaded with browns. Some even have prominent yellow lines or sunbursts on their scoots. This turtle is very rare in Minnesota, and they are located in small narrow lines bordering the south and north eastern areas of the State. When these turtles are found much further east, they are orange underneath. Only Minnesota’s population of wood turtles are yellow. These turtles stay very close to the river in a narrow line, and they don’t wander off (speaker....continued on page 12) Page 5


The Newsletter of the Minnesota Herpetological Society

T

he American alligator (Alligator mississippiensis) is a large, primarily nocturnal, semi-aquatic, carnivorous reptile with a range exclusive to the United States. Populations of the American alligator range from North Carolina, down the eastern seaboard through South Carolina and Georgia to the everglades of Florida, then west along the southern coast through Alabama, Mississippi, A r k a n s a s , Louisiana and finally to east Texas with a small population reaching the southeastern corner of Oklahoma. The primary habitat includes coastal w a t e r w a y s , swamps, marshes, lakes and slowmoving rivers. The name alligator stems from el lagarto or “the Lizard” in Spanish. Daudin “officially” described the alligator for science inn 1801 at which Photos and Text by Bill Moss time it was named alligator mississipiensis – with the last name being misspelled. The International Commission on Zoological Nomenclature corrected this error some 200 years later.

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large birds, snakes, bullfrogs, carnivorous mammals will take a large toll. From the air, hawks, eagles, jays, and a number of other bird species will feast on the hatchling and juvenile gators. Water doesn’t prove to be much better for them as they are taken by turtles, wading birds, and fishes. But the energy these baby alligators are providing to the fellow swamp inhabitants is part of what keeps the swamp healthy. These predators in turn, help to keep the alligator numbers to a ecohealthy, but sustainable number.

The American Alligator

The alligator is considered a keystone species to their habitat. This means that their presence in the swamps has a direct bearing on the ecological health of the environment in which they live. Right from the start, the alligator provides energy to the ecosystem by giving up a large number of it’s potential young in the form of eggs. These eggs are relished by a variety of hunting mammals such as raccoons, opossums and skunks. It’s estimated that 90% of the eggs laid will not make it one year. Of these, approximately 50% will not make it to hatching. The remaining 40% will succumb to an all-out assault by way of land, air and water. On land, Page 6

As the alligators grow, there are less and less predators, in many cases, former predators becoming prey. Once the gator reaches 5 feet in length, the only thing it has to fear (other than Man) are larger a l l i g a t o r s . Ultimately, the adult alligator becomes the top predator of the swamp. Even in this role, they provide services that allow for the continued health their environment. They help balance the ecosystem by preying on many of the animals that would otherwise multiply to unhealthy levels. The gators excavate what are known as “gator holes” which are depressions in the swamp that can be a much as 12-feet deep. These holes retain water after the remainder of the swamp has dried out during times of drought, providing a place for fishes to take refuge evaporating pools of water, and other fowl and mammal species to find food and water. Without the alligator, no such places would exist. The alligators also provide much-needed pathways through the heavy growth of swamp grasses that are otherwise virtually impassable by other animals trying to get from one place to another in the swamp. These animals then pay for this convenience by giving up the occasional individual to the alli-


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gators that may be laying in wait for them along this swampy “superhighway”,

Size, appearance, and other biological characteristics Alligators begin life as 9-inch long hatchlings that brightly colored with black and gold bands. The youngsters grow quickly, averaging 12inches per year for the first 5 to 6 years – a rate necessary to remove themselves from their role as a prey item. At this point, the growth of the females begins to subside while the male continues at this pace for a few more years. Full growth for females is on average about eight feet in length and about 200 lbs, with a 10-footer being very large. Males average around 12 feet in length and about 400 to 500 lbs with a 14-foot specimen being very large. There are reports of specimens of over 18 feet in length being killed in the late nineteenth and early 20 th century in Louisiana. E.A. Mcllhenny,(of Mcllhenny Tabasco Sauce) was a naturalist from that period wrote “Alligator ’s Life History”, the definitive reference of it’s time, wrote of shooting an alligator that was 19’ 2 “ in length as measured using the length of his rifle as a reference. Many scientists are skeptical of this report, and no evidence to support the claim was removed from the swamp (due to the great weight and distance out into the swamp, according to Mcllhenny) and therefore was never independently verified. As with other reptiles, alligators regularly shed their skin, more often during periods of rapid growth. Unlike most other reptiles though, the shed skin is in the form of very small pieces, almost like a dander that can be seen floating on the water.

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Reproduction Early spring marks the onset of the breeding season of the American alligator. In April, the males begin establishing and defending territory in which to court and breed the females, with the larger and more powerful alligators getting the preferred spots. This is a noisy time of year in the swamp as both males and females make their presence known by vocalizing via loud bellowing, grunting and head-slapping the water. Alligators, the most vocal of the crocodilians, will respond to one another ’s calls by returning the bellow. Some scientists believe that the alligators can recognize one another just by the vocalizations. Other noises and displays are used to either attract mates or to dissuade rivals. If signals don’t persuade the intruding male to turn tail and leave, a fight may break out. These fights over breeding rights are violent and often result in dismemberment or death. The courtship begins with the male and female tentatively approaching one another in the water. The female usually approaches the larger and more powerful male with her head tilted up, exposing her throat, a submissive body posture. The gators spend a lot of time gently caressing one another by rubbing their snouts against one anothers snout and neck. After some time, the male mounts the female, positioning himself vent to vent for penetration and fertilization. Alligators are not monogamous and after breeding, the male moves off to look for other females, and the female may court other males. There is evidence that a single clutch of eggs can have multiple fathers. The gravid female builds a nest on the shore using available vegetation and harvesting weeds from the water. Approximately 60 days after breeding, she lays 20 to 50 eggs in the middle of this nest and gently covers them with moist nest material. The combination of the rotting vegetation and the heat of the Sun combine to keep the nest at a reasonably constant temperature during the 65 day gestation of the eggs. During this time, the female keeps a close eye on the nest and any predator that attempts to raid the nest will have to deal with her protective instincts.

The dander-like shed skin comes off in small pieces.

Alligators possess no sex chromosomes to prePage 7


The Newsletter of the Minnesota Herpetological Society

determine the sex of the hatchlings. The incubation temperature of the eggs determines the sex of the alligator, a phenomenon known as TSD (temperature sex determination). This determination is made during a relatively short duration of the development cycle – approximately the third week. Temperatures below 86 deg F produce females, while temperatures 93 deg F and above produce males. The temperatures in between will produce a mix. Baby alligators begin to pip the eggs using a temporary egg tooth on the end of their snout, they also emit a call that notifies the mother to come dig them out. Upon uncovering them from the nest, the female gently picks the tiny hatchlings up between her powerful jaws and flips them into her mouth. When she has a full load, she carries them to the water, releases them, and goes back for more. Once they are all safely in the water, she climbs into the water with them where she exhibits maternal behavior unparalleled in the reptile world. The mother gator will protect her brood for as much as a year after hatching. Just as in humans, some of the juvenile alligators are slow to “move out of the house”.

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sides are a creamy, off-white color. Facial characteristics include a gray-green eye color and a speckled appearance around the lower jaw and under the eye. The look is almost one of a day or two of unshaven razor stubble. These “stubbles” are actually sensors called “ISOs” (integumentary sense organs) which are extremely sensitive to pressure changes. These organs can sense the pressure of a single droplet of liquid hitting the surface of the water nearby. This ability is an adaptation that has made crocodilians such successful top predators as they know when an animal is swimming or drinking in the water around them without actually being able to see it.

Eyes and Ears The eyesight is good and in color but the gator is probably quite farsighted. Due to the location of the eyes in the head, there is about a 30 degree angle in front of their nose where they do not see well. The eyes are surrounded by a light yellowish colored skin which help to reflect light, thus assisting night vision. There is a secondary eyelid that sweeps side to side across the eye called the nictitating membrane. This membrane is translucent in color and automatically closes to protect the eyes when the gator is underwater, thereby allowing for the primary eyelids to remain open while the eye is still protected. The underwater eyesight is not very good through these membranes, but shadows, objects and movement can be detected. The ears are located just behind the eyes and are covered by a moveable flap. This flap, just like the nostrils, closes when the gator submerges under water.

Locomotion

The ear flaps are just behind the eyes of this American alligator. Also visible are the pressure receptors giving the animal the appearance of having razor stubble.

Coloration As the alligators age, their coloration becomes increasingly bland, eventually becoming little more than an unspectacular gray color. Variations in coloration can be either genetically or environmentally influenced. The underPage 8

The adult alligator is a heavy-bodied creature that is not entirely graceful while moving about on land. The tail, which comprises about 50 percent of the total length of the gator, is much too heavy to be lifted off the ground and thus must be dragged. People tend to give alligators much more credit than they deserve for being able to run quickly on land. The truth is that top speed for an adult is 6 to 7 miles per hour – and then only for a short distance – probably not much more that 20 yards or so before the animal tires. Healthy adult humans can easily outrun an alligator on land. While simply moving from point A to point B, the alligator uses what is called the “high walk”.


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The alligator walks with the body mass high off the ground, the only thing dragging being the tail, and the legs are vertical under the body. The walking sequence is much like mammals in that they alternate front left to rear right and front right to rear left. When the gator is frightened, physics works to it’s disfavor and it is not able to support the weight while moving quickly. This results in the legs splaying out to the side and it dragging it’s belly on the ground while being propelled across land by the legs and the tail. In the water, the limbs are held to the sides and the alligators is propelled by the graceful side to side sweeping of it’s powerful tail.

Osteoderms The back of the alligator is covered with boney scutes or osteoderms, giving them their bumpy appearance. One function of these scutes is to provide protection to the alligator in the event of an attack as well as to serve in temperature regulation. These scutes contain hundreds of

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reverse effect takes place. Additional thermal regulation is accomplished by holding the mouth open much like a panting dog.

Osmoregulation Alligators, while able to live in somewhat brackish waters, do not possess the advanced abilities of the American or saltwater crocodile to osmoregulate, or rid their bodies of excess salts. Glands on the tongue are used for this purpose but with limited capability. Alligators (and crocodiles for that matter) can not drink salt water for the same reasons as humans.

The Brain The brain of crocodilians includes a cerebral cortex, the area of the brain where thought occurs, unique among reptiles. This advanced brain pushes the crocodilians to the front of the reptilian line where intelligence is concerned. There are many documented and anecdotal stories about the ability of the crocodilians to adapt to new situations, including learning habits of animals around them and learning and responding to a name or other stimuli such as a noise, light or regular, recurring events.

Circulation

The osteoderms are the boney scutes prominant on the backs of all crocodilians. They are used for protection and thermo-regulation

tiny holes through which blood passes. When the alligator is laying in the early morning Sun trying to warm up, the dark skin on it’s back absorbs the heat and transfers it into the scutes which act as little radiators by quickly warming the blood that is flowing through them. This blood is then circulated deep into the body mass thereby quickly warming the animal to it’s preferred body temperature of 88 degrees F. Conversely, if the alligator gets too hot, it can either move to the shade or the water where the

All Crocodilians have a four-chambered heart, as do mammals, other reptiles have only two. This advancement allows better efficiency of blood circulation and separates oxygenated blood from deoxygenated blood. Alligators, as all crocodilians, can control to a certain degree either by speeding up, or slowing down, blood flow to various parts of their body. It is advantageous, for example, that the alligator slow the blood flow to organs such as the lungs during extended periods of time under water. This preserves oxygenated blood for the heart and brain during a time when the lungs are not in use.

Dentition and Bite Force Alligators, as are all the members of the family “Alligatorinae” (American and Chinese alligators and all caimans) can easily be differentiated from their distant cousins, crocodiles, by the presence of an overbite. The top jaw is larger than the lower jaw so when the jaws are closed, the top teeth close over the lower jaw. The fourth tooth in the upper jaw of the alligators and their cousins, the caimans, is the largest tooth in the mouth. This is different than the Page 9


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crocodiles, which have the same size upper and lower jaws giving them a much toothier appearance. In addition, the fourth tooth on the LOWER jaw of the crocodile is the largest in the mouth. Alligators possess approximately 80 teeth. Not only are teeth often broken during hunting and combat, but they are shed on a regular basis. There is always a new tooth in development ready to replace the old or broken tooth. The jaws, being constructed using the mechanical advantages of the lever, with the addition of powerful constrictor muscles, can bite with enormous forces. Adult males alligators have had bite force measurements in excess of 2,500 pounds per square inch.

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People living with alligators are cautioned not to let children or pets play a r o u n d waters with known alligator populations, particularly at This x-ray clearly shows gastroliths dusk or in the stomach of a juvenile alligator dawn when the gators are most active.

Status in the Wild Feeding and digestion As hatchlings, alligators feed primarily on insects such as grasshoppers, butterflies spiders, and small fishes. As the gator grows, it will begin taking amphibians, small mammals, small fishes and birds, with the insects becoming less important in the diet. Finally, the adult alligator will consume anything of suitable size. This would include large fishes, deer, those raccoons and skunks that once preyed upon them as hatchlings, turtles and yes, even the family dog if it strays too close to the waters edge. Small people such as children can also be seen as prey to a large alligator. There is a palatal valve in the back of the throat that seals off the exterior mouth from the throat. This was a major evolutionary step that allowed modern crocodilians to breathe with only the tip of the nose exposed from the water, adding to their stealth. The valve also allows the gator to hold it’s mouth open while underwater (such as to hold a struggling animal) without taking on water. Alligators frequently swallow pebbles, rocks and other hard objects. These objects, also called gastroliths are stored in a gizzard-like part of the stomach and are used to assist digestion by grinding food and breaking down the bones and shells of the animals they consume. As if that isn’t enough, the crocodilian stomach contains acid levels as high as any animals on earth. Page 10

Due to over-hunting for the skin trade and lack of resource management, the American alligator was pushed to the brink of extinction as recently as the early 1970’s. At that time they were given Federal protection under the Endangered Species Act. Since the trade in wild alligator skins was now illegal, legal alligator farming became a source of both income and conservation. The alligator farmers are allowed to take a certain number of eggs from

Alligators are among the most social of all crocodilians and actually live in semi-structured groups. Scientists have identified over 18 signals, both visual and auditory, that alligators use to communicate with one another.

the wild to artificially incubate under controlled conditions with the agreement that they returned a certain number of hatchlings to the wild. This percentage was based on the status of the local population of alligators. Since this removed the pressure on the alligators in the


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wild, the numbers have returned to normal levels. This is pointed to as one of the major success stories of the concept of sustainable use – the theory being that if something is of value to people, and proper controls are placed on it’s use, people will protect the resource. Today, while the alligator still enjoys protected status in it’s native states, there are hunting seasons where a certain number of permits are issued based on local population health and/or overabundance.

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7. If you are young, are you looking to get married and have children one day? If so, will your wife/husband feel comfortable with your infant child sharing your home with a giant carnivore?

Taxonomy – Nomenclature of modern crocodilians The family Crocodylidae includes three subfamilies: Alligatorinae,Crocodylinea,and Gavialinae Subfamily Alligatorinae: Alligators, both Chinese and American Caiman, Broadsnout, Yacare, Brown, Spectacled Melanosuchus or Black caiman Paleosucus or dwarf caiman, Cuviers and Schnieders Subfamily Crocodylinae: All true crocodiles and dwarf crocodile Subfamily Gavialinae: Indian Gharial

Alligators as Pets It is quite common to see baby American alligators in your local pet store. While it is not in the context of this article to pass judgement on those wishing to have a pet alligator, the following points should be evaluated during the decision-making process. 1. There will be substantial investments in energy to keep the alligators at suitable levels. 2. Housing a 500 lb gator will be a challenge. 3. In the event Veterinary services are required, one just doesn’t throw a 12-foot long carnivore in the back of the minivan. 4. Alligators live for 50 to 70 years - do you know now what your interests will be in 1,5,10 or 50 years. 5. If the answer to 4 above is no, where will you take it once the novelty has worn off, or other life events dictate that you can no longer keep an alligator? Hint: Zoos, petshops and Humane Societies will not take them! 6. Are they legal where you live? Will they still be legal five years from now?

Do alligators make good pets? You’ll have to decide that one for yourself.

Suggested reading: www.crocodilian.com Adam Britton’s wonderful website devoted to crocodilians. Crocodiles and Alligators ed by Ross. Facts on File, 1989

Pub.

Handbook of Alligators and Crocodiles. Author Steve Grenard. Pub Krieger Publishing, 1991 Crocodilian Biology and Evolution. ed. by Grigg, Seebacher and Franklin. Pub. Surrey Beatty and Sons, 2001 Alligator ’s Life History. Author E.A. Mcllhenny, 1935 republished by SSAR, 1976 The Last of the Ruling Reptiles. Author Wilfred T. Neill. Pub. Columbia University Press, 1971 The Social History of the American Alligator. Author Vaughn L. Glasgow. Pub. St. Martin’s Press, 1991

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The Newsletter of the Minnesota Herpetological Society

(speaker...continued from page 5)

too very far from these areas. They over winter under the ice near the river banks or near any piles of logs. The Blanding’s Turtle (Emydoidea blandingii) is a medium to large turtle, and they have a pure bright yellow chin and neck. They can have a dark blue or black dome-shaped carapace with some muted spots or bars on the scoots. In this species, the males are much larger than the females. These turtles like very open areas along shallow or slow moving waters. They like muddy bottoms with large amounts of vegetation that can be found in marshy areas. The common map turtle raptemys geographica) is olive green to brown and has very thin yellow lines that create a pattern probably looking like maps. In the formal name, the word geographica refers to geography which is a word that everyone knows to mean a study of the delineation or systematic arrangement of constituent elements of the earth. These turtles are mostly aquatic and can be found in large and medium sized rivers. They like soft river bottoms and large areas for basking. They over winter under the ice in groups behind logs and rock piles. The Ouachita Map Turtles (Graptemys ouachitensis) are very plain except for their faces. They are most notable for having a large patch of yellow above the eyes. The rest of the neck consists of small narrow yellow lines. These turtles are large river animals where they like strong currents, large basking areas far from the shores, and much vegetation. They over winter in and near dams on the river. The false map Page 12

August 2004

turtle (Graptemys pseudogeographica) look similar to the Ouachita Map Turtle accept the yellow patch is more a long narrow line over the eyes which is commonly referred to as an eyebrow. Their shells can range from a light olive green in color to dark brown. These turtles can be found along the Mississippi River and its tributaries. They like soft river bottoms, large amounts of vegetation and much space for basking away from shorelines. They tend to over winter in groups and sort of pile up under the ice near dams. The ornate box turtle (Terrapene ornata) is not an aquatic turtle. They like very sandy areas like the sand prairies in Minnesota. They are also very colorful and patterned in shades of brown ranging from light to dark. If you want to read about Minnesota’s amphibians and reptiles, Barney Oldfield and John Moriarty wrote a book about them titled, of course: Amphibians & Reptiles Native to Minnesota published by the University of Minnesota Press in 1994. In this book you will find much more information about all the native species and many great pictures. Also, watch for John’s new book on turtles over the next few months. §

Volume 24

Number 8

Common Snapping Turtles and Styrofoam I recently received a message about a turtle die-off in NE WI and then had a follow-up call that one of the not-so-fresh dead turtles was cut open to examine stomach content. The turtle, a common snapper, had a bunch of white Styrofoam in its stomach that was one of those small night crawler boxes prior to consumption. The caller wondered if the smell of the worms had caused the turtle to be attracted to the box or if it simply went after the white Styrofoam. This is one of several reports I have received in recent weeks about turtle die-offs, usually involving a small number of turtles. Die-offs at this time of year are usually uncommon to non-existent here as most usually appear to be associated with over wintering mortality or post-emergence die-offs of weakened animals. I am writing to see if anyone has documented or sound anecdotal information regarding the threat of Styrofoam to turtles and whether the discarded night crawler box issue is cause for concern related to turtle survival. I tend to see these discarded boxes almost everywhere I see fishing activity, so this problem could be a potentially serious one for turtles if consumption causes mortality. Thank you, Robert Hay/Cold-blooded Species Manager/Wisconsin Department of Natural Resources Endangered Resources Program/P. O. Box 7921/Madison, WI 53707(608)2670849 Fax (608)266-2925

Robert.Hay@dnr.state.wi.us


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Vol. 24 (2004), No. 8  

Minnesota Herpetological Society Newsletter

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