That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

Captive insect-eating reptiles and amphibians (and perhaps invertebrates) are often plagued by nutritional deficiencies. A highly-varied diet is a great way to ensure adequate nutrition, but most keepers have access to only a few feeder-insect species; gut-loading (providing nutritious diets to feeders) is helpful, but detailed studies are lacking. While touring several Japanese zoos a few years ago, I was intrigued by the number of cricket species being bred as herp food, and resolved to investigate the species and diets I saw in greater detail. A recent article in Zoo Biology (2011, V. 30), which provides insights into carotenoid supplementation in three different cricket species, has re-sparked my interest. I’ll summarize below.

Carotenoids

Carotenoids are pigments that occur in plants. Animals, as far as is known, cannot manufacture carotenoids but rather must obtain them through their diet.

Carotenoids benefit the immune system by acting as antioxidants, function in the reproductive and other systems, and are believed partially responsible for the health benefits enjoyed by people who regularly consume fruits and vegetables.  We know little of their role in reptile and amphibian health, but many zoo nutritionists believe them to be important. Read More »

Like sowbugs (isopods, pillbugs), Amphipods are crustaceans that feature prominently in natural diets of many reptiles and amphibians.  They contain nutrients not found in insects, and are likely a rich source of calcium.  Several species are easy to collect and breed in captivity, but, unlike sowbugs, they rarely attract much attention from hobbyists (please see the article below for information on breeding sowbugs).  Whether you know them as Rock-Hoppers, Sand-Hoppers, Lawn Shrimp or any of the names above, one Amphipod or another likely makes its home near yours, and may be worth investigating as a food source for your pets.

Natural History

Amphipod diversity is astounding…over 7,000 species have been identified, and experts concede that they have no idea of the actual number in existence.

Found from pole to pole, Amphipods reach their greatest abundance in colder oceans.  Most live in marine environments, but a number have colonized fresh water and land; of the known terrestrial species, 45% dwell in caves or other subterranean environments.  They range in size from 0.8 to 1.6 inches long, and may be omnivorous, carnivorous or herbivorous. Read More »

Drawn by uneaten food, shed skins and other organic material, ants sometimes become pests around reptile, amphibian and invertebrate collections. As pesticides are harmful to humans and other creatures alike, eliminating ants in areas used by pets and people takes some care.  Today I’d like to highlight a substance that I used with great success in various zoos, and which works equally well at home – diatomaceous earth.

A Most Formidable Insect

Famed entomologist E.O. Wilson has demonstrated that ants “rule” many habitats, driving evolution and other processes to a degree that is hard to imagine.  What little work I’ve done with them has convinced me that they are, at the very least, extremely resourceful creatures. When working with Leaf Cutter Ants (Atta cephalotes) at the Bronx Zoo, I observed a dramatic increase in egg production shortly after empty nesting chambers were added to the colony’s enclosure – the workers somehow communicated to the queen that more space was available, and more bodies were needed. This likely holds true for other species as well – killing a few dozen workers will not reduce ant numbers but instead may set up a call for more eggs! Read More »

The Senegal Chameleon (Chamaeleo senegalensis) has long been common in the pet trade, yet there remain significant roadblocks to longevity and breeding. I recently re-read a 1990 study on prey choice in this species. I then considered it in light of newer research that established a link between Vitamin D levels and chameleon basking behavior. I believe both contain important findings that may be applicable to many species.

“What, grasshoppers again”!

In the study that examined prey choice in Senegal Chameleons (J. of Herpetology: V.24, N.4: p.383), different groups of chameleons were fed solely on either Long-Horned Grasshoppers or House Crickets. Over a period of several days, those lizards feeding upon crickets showed a strong preference for grasshoppers, and those on grasshopper-only diets favored crickets.

I have also observed this in other chameleon species under my care at the Bronx Zoo, and in a variety of reptiles and amphibians. As long as the species is acceptable, novel prey usually causes a very strong feeding response. Indeed, zookeepers and hobbyists commonly say that captive herps “become bored” with crickets, mealworms and other staples. Read More »

Almost every zoo building in which I’ve worked was home to roach (2-3 species) and House Cricket populations.  In most, pesticide use was not an option. An older animal keeper whom I befriended let me in on his favorite insect pest control technique – the molasses trap.  He was content to let management wonder how he did such a good job so, out of respect for him, I did not share the secret until he retired. Then, for a time, molasses traps became standard in several zoo buildings. Molasses is also useful in outdoor traps, where it never fails to turn up a variety of interesting species. I’ll expand on that below as well.

Pesticide Problems

House Crickets, roaches and other escaped “feeder insects” can be problematic in private collections. In the damp basements favored by amphibian keepers, Spotted Camel Crickets (Ceuthophilus maculatus, please see photo) may also set up housekeeping. These unusual creatures are very interesting in their own right, and I’ve featured them, and a large African relative, in several exhibits. However, most folks find their size, appearance and jumping abilities quite unsettling (please see comments in the article linked below – insect fans will find them very interesting!). Read More »