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The Natural History and Captive Care of Softshell Turtles – Part 2

The world’s 24 species of Softshell Turtles (Family Trionychidae) depart radically from the typical turtle body plan, and their behavior holds many surprises for those familiar with “normal” turtles.  In Part 1 of this article we looked at their natural history and diet, and discussed the basics of captive care.  I also relayed some of the difficulties inherent in working with these delicate creatures – difficulties that resulted in the loss of some huge and rare individuals of several species.  I hope you enjoy the following Softshell observations and stories. Read More »

Conservation Update – The Bizarre, Skin-Breathing Lake Titicaca Frog

The huge, aquatic, baggy-skinned Lake Titicaca Frog (Telmatobius culeus) has fascinated me since childhood, when I first came upon a group at the Bronx Zoo.  I returned again and again to stare as the unusual beasts – largest of the world’s aquatic frogs – did “push-ups” at the bottom of their cold aquarium (they breathe largely through their loose skin, and rock back and forth in order to increase the area exposed to the water).  Because the frogs lived for so long – nearly 30 years in one case – I was able to work with same individuals I had earlier observed once I began my zoo-keeping career. Read More »

New Dinosaur Resembled a Horned Lizard – On an Immense Scale

Horned Lizards (Phrynosoma spp., please see photo) and odd Australia’s Thorny Devil (Moloch horridus) have always reminded me of dinosaurs – I think it was their horn-bearing skulls.  I recall sketching my pet Horned Lizards and taking the (somewhat primitive!) drawings to the American Museum of Natural History for comparisons with the Triceratops skeletons displayed there.  This month (September, 2010), fans of such reptiles and dinosaurs were pleased to learn of the discovery of 2 new dinosaur species, one of which bore 15 horns upon its head – more than any other animal, past or present.

North America’s Lost Continent

The new species were uncovered in the Grand Staircase-Escalante National Monument, southern Utah, USA.  The area lies in what was once the “lost continent” of Laramidia, formed when an ancient sea separated the eastern and western portions of North America for millions of years.  The enforced isolation gave rise to innumerable bizarre insects, fishes, amphibians, dinosaurs and other creatures, many of which, it appears, have yet to be discovered. Read More »

Beyond Webs – Swimming, Spitting and Other Spider Hunting Methods – Part 2

Deinopis subrufaPlease see Part 1 of this article for a look at the unique hunting techniques employed by Fishing, Trap Door and other spiders.

Orb Webs

I’ve been avoiding “traditional spiders”, but wanted to include an observation I made over 20 years ago in Costa Rica.  I was tossing katydids into the huge orb webs that were abundant near my research station.  The web-owners (Nephila spp.) wrapped the insects in silk and then administered a bite.  Then I offered lubber grasshoppers – the same size and shape as the katydids, but equipped with immensely powerful rear legs.  On several trials, the spiders first pulled off the grasshoppers’ rear legs, then wrapped and bit the insects.  I imagine they were attempting to limit damage to the web. Read More »

Red-Eared Sliders Out-Compete Native European Turtles

European Pond TurtleRed Eared Sliders (Trachemys scripta elegans) have been introduced worldwide and are believed to negatively impact many species.  However, direct evidence concerning their affect on other turtles is scarce.  A recent study involving Sliders, Spanish Terrapins (Mauremys leprosa) and European Pond Turtles (Emys orbicularis) has shed some light on the subject.

Hardy Invaders

It’s easy to imagine that introduced Red Eared Sliders would create problems for native European turtles.  They are larger than many species favoring similar foods, breed rapidly, adjust well to human presence, and are very aggressive in the pursuit of food and basking sites.

I have noticed that Eastern Painted Turtles have declined in several habitats now occupied by Sliders, but am basing this on observation only, not study.  Others voice the same concerns, but again have been unable to document just what, if anything, the Sliders are doing to nudge-out the natives. Read More »

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