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

I’ve been fortunate in having had many adventures with reptiles.  Some took place in the exotic locales I dreamed of visiting as a child, but one of my first was situated in far less promising surroundings – the sewers below the Bronx, in NYC!

The Legend

I grew up hearing tales of huge alligators that supposedly cruised the sewers of NYC, warmed by the steamy air and gorging on rats, roaches and garbage.  In the 1950’s and 60’s, huge numbers of baby Spectacled Caimans (Caiman crocodylus), dubbed “alligators”, were sold to tourists visiting Florida.  In fact, I was presented with just such a creature by my grandfather.  As the story went, the “gators” wound up in sewers after being flushed or dropped there when they became ill or too large for their owners to manage.

My Golden Opportunity

When I was 10 or 11 years old, construction on the street outside my home gave me a long-awaited opportunity…the chance to sneak down into the sewers on an alligator hunt.  I couldn’t imagine a more fortunate set of circumstances, and felt sorry for the many children deprived of such a grand adventure!

Provisioned with a hook, line and pilfered cold cuts, I spent many summer afternoons stalking the mythical beasts below the streets of the Bronx.  I did see “wildlife” – rats, mice and roaches – but I did not catch any alligators (or infectious diseases, thankfully!).

Fortunately, my interests were wide, and with the aid of my books and the (very!) patient, kind-hearted folks at the American Museum of Natural History’s Invertebrate Department, I was able to determine that at least 3 different species of cockroach roamed the area.

The Reality of NYC’s Sewer Gators

Of course, NYC’s sewer system is a less than ideal home for crocodilians of any type – cold winter temperatures, a lack of sunlight and a poor diet would doom the creatures to brief lives, if ever they were there.

I recently expressed that opinion in an interview that was scheduled to air on the TV show “Monster Quest”.  However, I upon watching the episode I found that I had been “deleted” – hopefully because my comments were not “dramatic” enough, and not due to my poor on-air appearance!

Some Real NYC Crocodilians

About 10 years ago, a young Spectacled Caiman did wind up being caught in a filter at a water treatment plant on the Bronx River…perhaps the first solid evidence of a free-living crocodilian in NYC.  The animal had likely been dumped by its owner a short time earlier, but we could not trace its history.

A young alligator, released into a lake in Central Park a few years back, put Manhattan on the map as crocodilian “habitat”.

Working with Crocs

Happily, as time went on I was able to work with 15 or so species of crocodilians in zoos and the wild.  Please see the attached photos – the beast charging me is a marsh crocodile,  Crocodylus palustris, the long-snouted fellow being led into the net is an Indian gharial, Gavialis gangeticus, and the white specimen is an albino American alligator, Alligator mississippiensis.

 

Few amphibians exhibit a more dramatic change in appearance than male Crested Newts in breeding condition.  It really is something to see and, fortunately, breeding this species is actually quite feasible.  Breeding the crested newt in captivity also has great conservation value, as this species is in decline throughout Europe.  Furthermore, any information garnered is applicable to other species of concern, including the Alpine Newt, Triturus alpestris and the Swiss Newt, T. helveticus.

Natural History

The Crested Newt, which may reach 6.4 inches in length, is grayish to black above and orange with round black spots below.   

Living a largely terrestrial existence for most of the year, both sexes enter breeding ponds in late winter or early spring.  At this point, the males’ colors intensify and a large, comb-like dorsal crest develops. In both sexes the tail also becomes more paddle-like to facilitate swimming. Males also usually develop a white line along the sides of the tail, while reproductively active females sport a white line down the back.

Bringing Newts into Breeding Condition

While breeding may occur spontaneously in captivity, the most consistent results will be obtained if the newts are over-wintered at 36-42 F.  An increase in water depth may stimulate breeding outside of the normal cycle, but fewer viable eggs will be produced).

Upon emergence from hibernation, the newts should be housed in aquarium, or their terrestrial terrarium should be modified to provide a large water area. Resting sites such as cork bark slabs or basking platforms should be provided.

Due to their unique egg-laying behavior (females fold a plant leaf around each egg), crested newts slated for breeding are best housed in well-lit aquariums stocked with live plants.  The water should, if possible, be maintained at 54-65 F (a cool basement or garage often proves ideal).

We’ll take a look at raising the larvae next week. 

In  Part I of this article we looked at the importance of calcium, leaf litter and decaying wood in the diet of the African giant millipede (Achispirospreptus gigas) and its relatives.

Research Needed

Few field studies have been made of millipedes in the wild, and we therefore know little about their exact nutritional needs.  Based on experience with related species, and in the hopes of providing as many nutrients as possible, I began offering African giant millipedes a wide variety of food items.  With the help of colleagues here and abroad, I eventually arrived at a diet that has allowed me to breed a number of native and exotic millipedes, and to maintain individual animals for over 10 years.

A Useful Millipede Diet

In addition to leaf litter and wood (please see Part I of this article), I feed most millipedes a mixed salad of yam, carrot, kale, cucumber, apple, banana and a wide variety of other fruits and vegetables.  To this is added moistened insect gut-loading diet and tropical fish flakes, both of which supply necessary protein, and a bit of Forest Tortoise Food.

San Francisco Bay Prepared Tortoise Food is a convenient means of providing a wide variety of nutritious foods, and is readily accepted by many millipedes. I use this as an occasional supplement, or mix it into the regular salad.  All food offered is powdered with Reptocal.

 

Despite – or perhaps because of – its immense size, impressive armament of teeth and scarcity, the spectacular Crocodile Monitor Lizard (Varanus salvadorii) is often considered the crown jewel of private and public monitor collections.

I became acquainted with these formidable giants when they were first imported into the USA, and have cared for several at the Bronx and Staten Island Zoos.  Their husbandry is straightforward, but little is known about their lives in the wild.  Today I would like to summarize what we do know; please see the article referenced below for notes on captive care.

Description

Crocodile Monitors approach 9 feet in length – nearly as long as the famed Komodo Dragon, but less stoutly built.  There are recurring but unverified reports of much longer individuals.

The Crocodile Monitor’s prehensile tail often exceeds 5 feet in length.  The body is dark gray to black in color and marked with yellow spots, making for quite a spectacular appearance.  The snout area, especially in mature males, is large and bulbous.

Crocodile Monitors are unusually large for canopy dwelling lizards…the 3 foot long black tree monitor is far more typical.  However, aided by slender bodies, long claws and prehensile tails, they are very agile climbers.

Their teeth are unique among monitors, being serrated and over-lapping – possibly an adaptation for carrying large prey high above the forest floor.

Range and Habitat

Crocodile Monitors are found only in southern New Guinea.  Highly arboreal, they seem restricted to the canopies of mangrove swamps and lowland forests along rivers.

Status

Little studied due to the inaccessibility of their habitat, the Crocodile Monitor’s limited range renders it a conservation concern.  Listed on CITES Appendix II.

Reproduction

Females lay 6-12 eggs at a time, and up to 3 clutches per year in captivity (multiple clutches may be a function of food availability), with arboreal nest sites being favored.  In common with other tree-dwelling monitors, they likely deposit eggs in tree hollows and similar sites above ground in the wild.

Diet

Their natural diet has been little studied, but probably includes nearly any animal that can be overpowered.  Likely candidates would be cuscus, tree kangaroos, naked-tailed rats, bandicoots, possums, bats, birds, frogs, snakes, lizards, invertebrates and carrion.

An Undiscovered Giant in New Guinea?

Long a creature of legend, the Crocodile Monitor is the source of rumors alleging “Papuan Dragons” of 20 feet in length.  This specie’s habitat is inaccessible and barely explored….I like to believe that it or an as yet un-described monitor may indeed reach such lengths.

A Calculating Reptile

Like all Varanids, Crocodile Monitors are highly intelligent.  One huge adult that escaped its enclosure at the Bronx Zoo wedged himself behind a cage while attempting to hide from myself and a co-worker.  As we moved into position to flush him, he very deliberately peered around first one and then the other side of his hideout, trying to keep us both in sight.  When we backed off, he followed our progress, again changing position periodically to ascertain where we were.

The lizard remained stationary while we were near, and only ran when we gave him some space.  When he did move, the old fellow made unerringly for a more secure retreat that he had obviously “decided upon” while in hiding.

Further Reading

Please see my article Monitor Lizards: an Overview for information about the captive care of this and related species.

A comprehensive field report on the crocodile monitor’s habitat is posted here.

 

Crocodile Monitor image referenced from wikipedia and originally posted by Ltshears

Our favorite animals’ own holiday, Reptile Awareness Day (RAD), will soon be upon us. On Wednesday, October 21st, herp enthusiasts can participate by doing something special for reptiles – educate someone about reptiles, clean up a reptile habitat, do something special for your pet, make a donation to a conservation organization…the possibilities are endless.

The Bronx River as Herp Habitat?

I’ve been involved in a few such endeavors over the years. One of the most gratifying was in conjunction with Bronx River Restoration. Neighborhood children were recruited to help remove debris that had accumulated along that part of the Bronx River that passes through the Bronx Zoo. A surprising array of reptiles and amphibians (i.e. snapping, painted and musk turtles, green and bull frogs, dusky salamanders) live along the river, but they need a hand on occasion.

We also trimmed overgrown banks to let in sunlight and improve basking opportunities for resident Eastern painted turtles and added tree stumps to the shallows. On return visits to the river, the children were happy to see both turtles and water snakes utilizing the new basking spots.

Water Snakes in NYC

Another surprisingly effective project that I enjoyed was the reintroduction of northern water snakes to the banks of the Bronx River and nearby ponds. Working on conjunction with several wildlife agencies, I collected water snakes from approved areas and released several gravid females. I also held back a few animals for captive breeding, and released the young (1 huge female gave birth to 89 live young, a near record!).

I’m delighted to report that the water snakes are breeding in their new habitat. If this can be accomplished in the center of the country’s most densely populated city, just imagine the potential that exists elsewhere!

Please Note: Reintroduction programs must be carefully researched and approved by your state Fish and Wildlife Agency.

Have Fun, Help Reptiles and Win Prizes!

Forgotten Friend Reptile Sanctuary, a reptile rescue and education organization located in Elizabethtown, PA, is sponsoring a contest in support of Reptile Awareness Day (RAD). So lending a hand to reptiles will not only feel good…it may just earn you some great prizes as well (Including a $50 gift card from That Fish Place/That Pet Place)!

To enter, simply post a note describing your “reptile friendly” good deed on Forgotten Friend’s site.

Radio Broadcasts

Anyone in the Central Pennsylvania area should be sure to tune in to the morning shows at FM 97 or WJTL FM 90.3 on October 21st – Forgotten Friend Reptile Sanctuary representatives will discuss their important work and suggest ways that we can help to make the world a better place for our reptile friends.

Amphibian Awareness Day?

We don’t have an Amphibian Awareness Day yet, but please don’t forget that frogs, salamanders and caecilians also need a hand. As you can see from the photo, even the youngest herpetologists among us can express real tenderness towards small creatures (the sturdy little fellow pictured here usually goes through life like a bulldozer!). Children are the conservationists of the future – include them in your hobby if at all possible.