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Giant Snapping Turtles – Size Records from a Survey of 84,000 Turtles

Stories concerning immense Snapping Turtles (Chelydra serpentina) abound wherever this impressive reptile occurs, but most are difficult to substantiate.  I’ve kept and observed this species from childhood.  Once I embarked upon a career in herpetology, I had the good fortune of meeting a great many impressive Snapping Turtles and Snapping Turtle researchers, and was able to gather information on some true giants (I’ve encountered fewer Alligator Snapping Turtles, but one under my care weighed 206 pounds!).  Today I’ll highlight some interesting facts and figures concerning larger-than-average snappers.  I’d also like to draw your attention to a late-breaking threat to their survival.  Sadly, a bill currently before the NYS Assembly will, if passed, allow commercial trapping of this magnificent animal.  Please see below for further information, and check out this posting by turtle conservationist Allen Salzberg (scroll down to “Snapping Turtles under Attack”) for information on how to register your opposition to this ill-advised legislation.

Snapper smile Record-Sized Snappers

The largest Snapping Turtle I’ve handled tipped the scales at 68 pounds, and added more weight over time (please see photo).  Its “straight line” carapace length was 18.6 inches (“straight line” means that the measurement was taken via calipers, as is done for published accounts; stretching a tape measure over the shell’s curve adds to the measurement).  The largest wild-caught individual appears to be a 22 inch-long 76.5 pound behemoth captured in New Hampshire (most record-sized Snappers and Alligator Snappers originate from the northern part of the range).  Turtles artificially fattened in captivity, such as the 82-86 pound animal frequently cited in field guides, are known.

How Common are Giant Snapping Turtles?

I gleaned the following information from conversations with colleagues and various reports.  The turtles involved were collected in the northeastern USA, for the commercial food market, over a 28-year period ending in the early 1990’s. Read More »

Africa’s Deadliest Snake? Black Mamba Habits, Venom and Behavior

As any experienced reptile enthusiast knows, accounts concerning the size and aggressive nature of various snakes are usually highly exaggerated. The Black Mamba, however, comes close to living up to the legends that surround it, and has long been among the most feared of all African snakes. In the course of a lifetime spent working with venomous snakes in the wild and captivity, I’ve come to regard it as deserving of a special degree of respect. Today we’ll take a look at its natural history and behavior.


The Black Mamba is the longest of Africa’s many venomous snakes. It is slender in build and averages 8-9 feet in length, but 14 footers have been recorded. Also very agile and fast-moving, several individuals have been clocked at 12.5 miles per hour. Black Mambas often travel about with the head held high, in a manner similar to that of North America’s Black Racer.

Black mamba feeding

Uploaded to Wikipedia Commons by Tad Arensmeier

The “black” part of its common name is derived from the color of mouth’s interior, which is displayed when the animal is threatened (North America’s Cottonmouth behaves in a similar fashion). The body color may be various shades of brown, olive or gray, but is never black.

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“My Emperor Scorpion Has Babies…What Should I Do”?

Emperor Scorpions give birth to live young, and most hobbyists are thrilled when this happens.However, scorpion reproduction breaks many of the “rules” that apply to other pets.For example, a female that has been alone for 14 months may one day be found with 30 tiny white youngsters, or “scorplings”, on her back!I’ve written about scorpion breeding and care in detail elsewhere (please see links below), but thought that an article describing what steps one should take when first discovering youngsters would be useful…especially if your female turns out to be a less-than-perfect mom and begins eating her new creations!Please also be sure to post your questions and concerns below, as scorpion births often take owners by surprise, and I’ll be sure to get right back to you.

Predicting Scorpion Births

In the wild, some Emperor Scorpion populations breed seasonally, while others may reproduce year-round.Captives can mate and give birth during any month of the year. Further complicating our ability to predict births is the fact that females seem able to both store sperm and delay giving birth if conditions are not ideal.Environmental factors such as temperature and stress may also affect the youngsters’ development.Even under ideal conditions, the gestation period may exceed 1 year, although a range of 7 to 10 months is more common.

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Odd and Giant Snake Meals – Sticks, Antelopes, People, Siamese Cats…

Gaboon ViperMany interesting reptile field research reports are published in professional journals that are not available online to non-subscribers. Fortunately, I’ve long had access to many of my favorites, including Copeia, Herpetologica, and Herpetological Review.  From time to time I like to provide summaries of interesting reports that I have read and enjoyed.  Today’s article covers some very unique snake feeding observations drawn from recent publications and my own experiences in the field and among zoo animals.  Please be sure to post your own observations below, thanks.

When Prey Exceeds Predator’s Mass

The largest snake meal that I’ve personally witnessed was a 60 pound White-Tailed Deer taken by a 17 foot-long, 215 pound Green Anaconda, Eunectes murinus, in Venezuela. A 130 pound Impala consumed by an African Rock Python, Python sebae, is the largest fairly reliable meal I’ve been able to document (please see article linked below).

But in terms of the ratio of prey size to snake size, a Red Duiker (small antelope) eaten by a Gaboon Viper, Bitis gabonica, beats most accounts hands down.  The antelope outweighed the snake by 4%!  In addition to being the largest meal recorded for this species, this is also the first record of an ungulate being taken by a Gaboon Viper in South Africa.  I’ve worked with Gaboon Vipers in zoos, and know how well-adapted they are for taking large, infrequent meals, but I was still quite surprised by this observation. Read More »

Important Supplies for Pet Tarantulas – a Zoo Keeper’s Notes

Among the world’s 900+ tarantula species (Family Theraphosidae) we find spiders of every conceivable size, description and lifestyle, some of which make interesting, long-lived pets.  I had the chance to work with many during my zoo career, and most of the supplies that I relied upon are now readily available to hobbyists.  Whether you are just starting out or looking to add additional species to your collection, the following information will assist in your decision.  Please be sure to post any questions or observations about pet tarantulas below. 


Setting up the Terrarium

Tarantulas are best kept in screen-covered aquariums, reptile cages or plastic terrariums.  “Extra high” styles are best for Pink-Toed Tarantulas and other arboreal species.  Be sure to use cage clips on the cover, as tarantulas can climb glass and are incredibly strong.  A 10-15 gallon aquarium is adequate for all but the largest individuals.

Goliath Bird eating Spider

Uploaded to Wikipedia Commons by Snakecollector

All tarantulas require a dark hiding spot.  Burrowing species such as the Goliath Bird-Eating Spider will dig their own caves if provided deep substrate. Sri Lankan Ornamental Tarantulas and other arboreal species will utilize the underside of an upright piece of cork bark.  Most also accept inverted flower pots and plastic reptile caves. Read More »

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