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Feeding African Clawed Frogs – the Two Best Diets

African Clawed FrogProviding a wide variety of live foods is one of the main stumbling blocks to keeping most frogs healthy in captivity.  African Clawed Frogs (Xenopus laevis, and several related species), however, take non-living foods (i.e. carrion) in the wild, and therefore are quite easy to accommodate in captivity.  Today I’d like to highlight two different diets that have enabled some of my African Clawed Frogs to reach 20+ years of age, and to breed as well.

Note: Dwarf African Frogs, Hymenochirus spp., require an entirely different diet comprised of small live invertebrates.  Please see this article for details.  Another relative, the bizarre, skin-brooding Surinam Toad, Pipa pipa, is also a live food specialist (please see photo and this article. Read More »

Reptile and Amphibian Foods – Breeding and Rearing Grasshoppers and Locusts

Hooded GrasshopperThe Domestic or House Cricket is perhaps the world’s most popular herp food, the closely-related locusts, grasshoppers and katydids have been neglected as a food source here in the USA.  However, many are easily collected and bred in captivity, and offer important nutrients lacking in commercially-bred insects.  What’s more, they are colorful, active and extremely interesting to work with – don’t be surprised if you begin keeping them as more than just a food item!

Natural History

Grasshoppers, crickets, locusts and katydids are classified in the Order Orthoptera.  Over 20,000 species, inhabiting environments ranging from deserts to mountain tops, have been described.  The USA is home to 1,000+ species.

Many grasshoppers sport a fantastic array of colors and shapes; some are barely visible to the naked eye, while others, such as New Guinea’s Phyllophora grandis, top 5 inches in length (please see photo of a Hooded Grasshopper). Read More »

Frog Leg Trade Kills Billions of Frogs Annually and Threatens Species’ Survival

Indian BullfrogUnprecedented declines in amphibian populations have been much in the news lately.  Linked to a number of factors, including an emerging disease (Chytrid fungus infection), frog extinctions are being documented the world over, and herpetologists are scrambling to save those that remain.  Yet the international trade in frog legs remains largely unregulated, and is considered by many to serve only a limited market for “exotic foods”. However, a recent report, Canapés to Extinction: the International Trade in Frog’s Legs (July 26, 2011) reveals the trade’s shocking volume and impact on frogs and their habitats.

Trade Kills 1,000,000,000+ Frogs in US Alone

The extent of the frog leg trade in the USAis surprisingly large.  The USAannually imports 4.6 million pounds of frog legs, representing an estimated 1.1 billion frogs, and 4.4 million pounds of live frogs!   These figures, and those mentioned below, are bare minimums, as they do not include locally farmed and collected frogs and those that are not reported to regulatory authorities.  Read More »

Lizard Societies – Great Desert Skink Families Build Communal Homes

Blue Tongued SkinkTwenty of the world’s 5,000+ lizard species have been shown to live in family groups (i.e. the Prehensile Tailed Skink, Corucia zebrata, and the USA’s Desert Night Lizard, Xantusia vigilis).  Field studies have now revealed that one social lizard – Great Desert Skink or Tjakura, Liopholis kintorei – actually constructs complex, long-term dwellings and lives in extended family groups.  Native to the red sand plains of central Australia, it is the only lizard known to exhibit such highly-evolved social behavior.

Natural History and Conservation

The Great Desert Skink is stoutly-built, much like the familiar Blue-Tongued Skink (please see photo) and sports rust to burnt-orange coloration that closely matches the red sands in which it lives; its Aboriginal name, Mulyamiji, means “red nose”. 

The diet is comprised largely of beetles, spiders and other invertebrates, with termites being an important food source for part of their active season.  Small snakes, lizards and some vegetation are also taken.  Please click here to view a photo of this most attractive lizard.

The Great Desert Skink’s range has greatly decreased in recent years, and it is classified as Vulnerable by the Australian Government (please see article below for conservation plan).

Skink “Towns”

The degree of social behavior exhibited by the Great Desert Skink is unprecedented among lizards, and has shocked the herpetological community.  Researchers from Macquarie University and Parks Australia have discovered that families comprised of a breeding pair and several generations of offspring cooperatively build complex tunnel systems which are occupied for at least 7 years.

Their subterranean homes have up to 20 entrances and separate latrine areas, and may cover an area spanning 50 feet or more.  Tunnel construction and maintenance duties are carried out by family members based upon size, with the largest individuals doing most of the “heavy lifting”…all seem to contribute some effort, however.

Mate Fidelity and Family Ties

Australian Red SandMated pairs of Great Desert Skinks remain together for years.  Females seem to copulate only with their mate, but 40% of male skinks father young “outside” of their primary relationship.  The young are born alive and remain within the tunnel system of their birth, with their parents and siblings, for several years.  How and when they disperse and breed is being investigated.

Biologists hope that further studies of Great Desert Skink communities will reveal insights into the evolution of social behavior in reptiles and other creatures.

 

 

Further Reading

Natural History and Conservation of the Great Desert Skink (Australian Government Report)

Central Australia’s Red Sand Habitats

Social Behavior in the Prehensile-Tailed Skink

 

New Test for Cryptosporidiosis, an Incurable Disease of Snakes and Lizards

Corn Snake and PreyA decade or so ago, Cryptosporidiosis became recognized as a major concern in captive snake and lizard collections.  Caused by a one-celled parasite known as Cryptosporidium varanii, the disease remains incurable to this day.  At the Bronx Zoo, where I worked at the time, tests showed that many snakes already in our collection, along with wild and pet reptiles, might be harboring Cryptosporidium.  But diagnosis was difficult and errors were common, resulting in the institution of expensive and time-consuming isolation protocols for new and sick animals.  So I was happy to learn of a newly devised test that ensures early, accurate diagnosis of Cryptosporidium…it will surely prove useful to pet keepers and zoos alike.

Crypto and the Pet Trade

A number of factors render Cryptosporidiosis as a major concern, including the popularity of reptile pets and the fact that the parasite can be transferred to people.  While not often of major concern to healthy adults, Crypto, as it came to be known, is a danger to immune-compromised individuals (please see article below).  A recent survey of 672 pets revealed that 1 in 6 of the Corn Snakes and 1 in 12 of the Leopard Geckos tested harbored Crypto in one form or another.  Read More »

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