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

 I’ve had the good fortune of caring for 15-20 monitor species during my zoo career. From the diminutive Storr’s to the massive Water, Lace, Crocodile and Komodo Monitors, all have instilled in me the feeling that they were, somehow, “more complicated” than other reptiles. Indeed, recent studies have confirmed that they are, among lizards, highly advanced.  While some are too large for the average household, several moderately-sized and even dwarf varieties are being bred by hobbyists, and all make fascinating and responsive captives.

The following information can be applied to the care of Savannah, Black Tree, Nile, Merten’s and most other monitors.  However, details vary; please post below for information on individual species, and be sure to add your own thoughts and observations on monitor lizard care.

Natural History

Seventy-three monitor species (Family Varanidae) range across Asia, Africa and Australia. Nile Monitors (Varanus niloticus), introduced to south Florida, are a major environmental concern there.  Lace Monitors (V. varius) and other large speciesare usually the dominant predators in their habitats.  While most dwell in warm regions, Desert Monitor (V. griseus) populations in Kazakhstan are adapted to Vermont-type winters.  Read More »

With their highly-permeable skins, amphibians absorb ammonia and other pollutants over a greater surface area than do fishes.  Surinam Toads, Axolotls, tadpoles and other aquatic amphibians are most at risk from poor water quality, but even terrestrial species such as toads and Fire Salamanders can quickly succumb to water-borne toxins while soaking in terrarium pools. Keeping their water clean, both visibly and chemically, can be quite a challenge.

General Considerations

Natural History

Your pet’s natural history will determine the type of filter that should be used.  For example, newts and Dwarf Clawed Frogs will be stressed by fast currents, Hellbenders are extra-sensitive to water quality, many species are prone to bacterial attack in highly-oxygenated waters, and so on.  Please post below if you need help in selecting a filter.

Types of Filtration

Biological filtration, wherein aerobic bacteria convert ammonia to less harmful compounds (nitrites and nitrates), is the most important of the three basic filtration processes. Ammonia enters the water via dead animals and plants, uneaten food and the occupants’ waste products. The organisms involved in the process, Nitrosomas and Nitrobacter bacteria, live on substrates that are bathed with oxygenated water (i.e. gravel, filter pads). Read More »

Mauritius, an island nation off the coast of southeast Africa, is best known to naturalists as the site of the Dodo Bird’s extinction (Mauritius also is, in a sense, the reason I was hired by the Bronx Zoo and spared life as a lawyer – see article below for the story!).  Herp enthusiasts, however, know it as the habitat of several unique reptiles, all of which are now very rare or extinct. But we can delight in some news just released by the Durrell Wildlife Trust – a new population of the Round Island or Keel-scaled Boas, Casarea dussumieri, will soon be established in the wild.  This unusual snake disappeared from nearly all of its range in the 1860’s, and its return is the culmination of 40 years’ worth of captive breeding and habitat restoration efforts.

Status and Conservation

The Round Island Boa is now confined to Round Island, a tiny speck of habitat where perhaps 500-1,000 individuals survive.  A single wild population and limited number of captives place it at continued risk of extinction.  The new population to be established on another Mauritian island (where the snake formerly lived) is a vital step towards ensuring the species’ survival.  Read More »

People are often surprised to learn that Land or Terrestrial Hermit Crabs engage in complex social behaviors, are capable of communicating via “chirps” and, with proper care, may live for over 20 years.  I’ve had the pleasure of working with them at home, in zoos and the wild, and have even kept the massive, awe-inspiring Coconut Crab.  Please read on to learn about their care and natural history, and be sure to post your own thoughts and experiences.

Hermit Crab Natural History

The Purple-Pincher or Caribbean Hermit Crab (Coenobita clypeatus) is the most common pet trade species.  It ranges throughout the Caribbean, reaching as far north as Florida and Bermuda.

Some populations live at altitudes of over 3,000 feet, but females return to the sea, usually in one massive migration, to spawn. The larvae, or zoea, float about with plankton for 2 months, after which they take up life on land. Read More »

In 1990, the IUCN’s Declining Amphibian Populations Task Force, to which I belonged, was one of the few large scale efforts addressing what is now known as the “Disappearing Amphibian Crisis”.  Today, with legions of biologists and hobbyists at work on the problem, we still do not fully understand why nearly 200 species have become extinct in the last 20 years – a rate 200x that of what might be “expected”.  But we do have some insights, one of which was highlighted in a recent journal article (Philosophical Transactions of the Royal Society (Biology) .  It appears that stress, much of which is in response to what we are doing to amphibian habitats, is worsening the effects of normal pathogens and diseases.

Parasites and Insecticides: a Confusing Scenario

As the reality of worldwide amphibian declines became apparent, herpetologists and private citizens began noticing increasing numbers of deformed and dead frogs. In 1995, school children in Minnesota made headlines when they found dozens of deformed frogs in a local pond. Since several chemicals are known to cause growth abnormalities, researchers began focusing on pollutants. At the Bronx Zoo, I worked with a veterinarian who studied African Clawed Frogs, and was amazed to see ovaries develop in males that had been exposed to Atrazine (a common insecticide). Read More »