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

 

Well, the name says it all – Titanoboa!

Snake-oriented web sites will be alive this week with news of the discovery of fossils belonging to a snake of unprecedented size.  Writing in the journal Nature, researchers from the Smithsonian Institute and the University of Florida note that Titanoboa was larger than the contrived serpent that “tries to eat Jennifer Lopez in the movie Anaconda” (Ms. Lopez and company appeared at the Bronx Zoo when that movie was in progress, seeking technical advice.  I was a reptile keeper at the time, but, sadly for me, the powers that be declined to become involved!).

Colombia‘s Anacondas…now and then

An artist’s rendition of the huge beast casts it much like a very large anaconda.  Indeed, the giant is believed to have kept to Colombia’s marshy areas, home to modern-day anacondas.  Titanoboa roamed Colombia during the Paleocene Epoch, just after the extinction of the dinosaurs (approximately 65 million years ago).

Chasing Today’s Giants

There is only one reasonably reliable account of a modern-day snake measuring over 30 feet in length.  A reward offered by the Bronx Zoo for another stood uncollected for nearly 100 years.

I’ve done my level best to find a record breaking anaconda, and I like to think that she is out there somewhere.  The largest anaconda that I came up with was just over 17 feet long and weighed in at 215 pounds – no Titanoboa, but then again not an easy animal to wrest from the muck of a Venezuelan swamp either.  For the full story and some photos of myself and others with that snake, please see my article Hunting Anacondas in the Venezuelan Llanos.

 

 

A recent article (Jan. 2009) in Physiological and Biochemical Zoology has shed light on why spitting cobras nearly always hit the eyes of whatever creature they are aiming for, be it secretary bird (a predator), gnu (a trample hazard) or person.

Perfect Aim Not Needed

Utilizing high speed photography and EMG tests, researchers established that the snakes contract their head and neck muscles just before ejecting venom.  The contractions rotate the head and jerk it sharply from side to side, so that the venom forms a complex geometric spray pattern as it approaches its target.  As long as aimed in the general direction of the face, the venom contacts the adversary’s eyes nearly 100% of the time.

Keeping Zookeepers on Their Toes

I have worked closely with several types of spitting cobras.  Like many Elapids (cobras and their relatives), they are alert and quick-moving, and seem, at least on the surface, to be quite intelligent.  These traits, combined with their ability to both bite and “spit”, renders them quite a handful in captivity, and they provide much fodder for zookeepers’ tales.

Perhaps He Thought They Needed Exercise?

In one very bizarre incident from my Bronx Zoo days, a visitor held his son up so that the child could kick in the glass of an exhibit housing 3 black-necked spitting cobras (Naja nigricollis)!  As might be expected, the breaking glass caused a great deal of agitation to both the snakes and some of the other visitors…I say “some of” because nearly as many people were pushing towards the exhibit as were running away (those wacky New Yorkers!).  Fortunately, all emerged unscathed, and the snakes were recovered quickly.

Cobra Hunting to Start the Day

Another zoo adventure began when, still bleary-eyed after a few mugs of espresso very early one spring morning, I discovered that 3 red spitting cobras (Naja pallida) had vacated their holding cage overnight.  The ancient plastic goggles I used around spitters were fine for exhibit work, but rendered me nearly blind in the dim, cluttered recesses of the reptile house’s basement and storage areas.  Lifting the goggles briefly to peek under something was terrifying, but so was leaving them on and seeing only unidentifiable shadows.

One colleague, goggles perched on his forehead, spied a snake and grabbed it with tongs, neglecting to lower the goggles in the excitement.  Fortunately, the trapped serpent vented its wrath by biting the tongs, and not by spitting at my partner’s face!  After a few sweaty, suspense-filled hours, all 3 snakes were re-captured…whereupon I ordered new goggles!

I’ve also had run-ins with the spitting cobra’s much larger relative, the king cobra…please see my article A Close Call With a King Cobra http://blogs.thatpetplace.com/thatreptileblog/2008/06/ for more cobra tales.

Image referenced from Wikipedia, first published by LA Dawson, and shared under the Creative Commons Share Alike-2.5 License.

 

Click: The Natural History of the Ball Python, Python regius: Ball Pythons in the Wild – Part 1, to read the first part of this article.

Status in the Wild

This species is threatened across large areas of its range by collection for the food, leather and, in the past, pet trade.  Today the vast majority of animals in the pet trade are captive bred.  It is listed on Appendix II of Cites.

Diet

Grassland rodents comprise the majority of the diet.  Recorded prey species include cane rats, Nile rats, gerbils, jerboas, jirds and zebra mice.  They also feed upon shrews and ground-nesting birds, and hatchlings may take lizards.  Wild individuals often favor particular prey species, and may be difficult to habituate to commercially available rats and mice when taken captive.

Ball pythons often inhabit areas subject to long periods of hot, dry weather, during which food is scarce.  Animals in such populations may aestivate in mammal burrows or similar underground shelters for several months.  It is theorized that the internal circadian rhythms of these pythons may be responsible for the long fasts that captive animals often undergo.

Reproduction

Females produce typically 6-7 large eggs at yearly or less frequent intervals.  Eggs are typically laid in abandoned aardvark or rodent burrows, and hatch after an incubation period of 3 months.  In common with other family members, female ball pythons remain coiled about the eggs during this time, providing protection and temperature/humidity modification.

Female pythons of various species have been shown to actively raise the temperature of their clutch by coiling about the eggs and “shivering”.  In captive situations, I have observed incubating female blood pythons (Python curtus) and Burmese pythons (P. molurus bivittatus) to raise their eggs by 7F above the ambient air temperature.  Field research conducted with ball pythons, however, indicates that incubation mainly functions to conserve egg weight by preventing water loss.

The young measure 10-17 inches upon hatching, and reach sexual maturity at 3-4 years of age, by which time they are approximately 3 feet in length.

Economic Importance

Ball pythons are heavily utilized as food by people throughout much of their range, and are harvested for the leather trade as well.  Until captive bred stock became widely available, huge numbers were collected for the pet trade and exported to Europe, Japan and the USA.

Miscellaneous

The common name of this snake is derived from its habit of coiling into a tight ball, with the head hidden within the center, when threatened.  Once so situated, it is difficult to uncoil the snake, and it will remain so even if rolled about (not recommended!).  However, some ball pythons surprise attackers (and annoying keepers!) by biting savagely when disturbed.  Actually, a number of other pythons and unrelated snakes utilize a coiled defensive posture, but in none is it so well developed as the ball python.

 

An extensive CITES-generated study of ball python populations and management in Ghana is posted at:

http://www.stevegorzulapresents.com/study_royal_python_ghana.pdf

Ball Pythons in the Wild

 

As recently as the early 1990’s, the now popular ball python was considered a troublesome captive, due largely to the prevalence of wild caught adults in the trade.  Today it is widely bred in captivity, but certain of its natural traits continue to affect how we go about keeping it as a pet. We’ll take a look at some of those traits, and then go on to captive care in future articles.

Physical Description

Although small as far as pythons, go, this species is very thickly-built.  Ball pythons average 3-5 feet in length, with occasional (and now only rarely encountered) specimens reaching 6 and even nearly 7 feet.  It is the smallest African representative of the genus Python, but not the smallest African python per se.  That title goes to the West African burrowing python, Calabaria reinhardtii, which rarely exceeds 3 feet in length.

Ball pythons are dark brown to nearly black in color and marked with numerous, generally oblong blotches of tan, light brown, reddish-brown or yellow-orange.  The color of wild specimens varies tremendously among different populations, with pied and even albino individuals reportedly being encountered more frequently than is usual among other snake species.  This may account for the ease in which captive color morphs are produced, although incubation temperature seems to affect the color pattern as well.  The savannahs of Ghana are known for their predominance of yellow-orange ball pythons, which are much favored in the pet trade.

Range

Sub-Saharan Africa, from Senegal on the west coast northeast through Mali to western Sudan and southeast through Guinea-Bissau to the Gulf of Guinea, then east to the Central African republic, possibly Zaire, and Uganda.

Although typically described as being native to “Tropical West Africa”, the ball python actually has a fairly wide distribution across central and into parts of east Africa.  In addition to the aforementioned countries, ball pythons have been recorded from Niger, Chad, Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Burkina Faso, Nigeria, Benin and Cameroon.

Most of the parent stock of today’s captive population apparently originated in Toga and Ghana.

Habitat

Ball pythons are snakes of open, often arid habitats – savannahs and other grasslands, sparsely forested woodlands, overgrown fields and the borders of agricultural areas.  They typically shelter in mammal burrows, termite mounds or hollow logs.  Although largely terrestrial in some habitats, ball pythons will climb, and often occupy tree hollows where such are available.

Where undisturbed, they frequent barns, tilled fields and village outskirts, drawn by large rodent populations.   Ball pythons do not occur in forests or thickly-wooded habitats, but will colonize such areas when they are cleared for agricultural use.

 

Status in the Wild

This species is threatened across large areas of its range by collection for the food, leather and, in the past, pet trade.  Today the vast majority of animals in the pet trade are captive bred.  It is listed on Appendix II of Cites.

Diet

Grassland rodents comprise the majority of the diet.  Recorded prey species include cane rats, Nile rats, gerbils, jerboas, jirds and zebra mice.  They also feed upon shrews and ground-nesting birds, and hatchlings may take lizards.  Wild individuals often favor particular prey species, and may be difficult to habituate to commercially available rats and mice when taken captive.

Ball pythons often inhabit areas subject to long periods of hot, dry weather, during which food is scarce.  Animals in such populations may aestivate in mammal burrows or similar underground shelters for several months.  It is theorized that the internal circadian rhythms of these pythons may be responsible for the long fasts that captive animals often undergo.

Reproduction

Females produce typically 6-7 large eggs at yearly or less frequent intervals.  Eggs are typically laid in abandoned aardvark or rodent burrows, and hatch after an incubation period of 3 months.  In common with other family members, female ball pythons remain coiled about the eggs during this time, providing protection and temperature/humidity modification.

Female pythons of various species have been shown to actively raise the temperature of their clutch by coiling about the eggs and “shivering”.  In captive situations, I have observed incubating female blood pythons (Python curtus) and Burmese pythons (P. molurus bivittatus) to raise their eggs by 7F above the ambient air temperature.  Field research conducted with ball pythons, however, indicates that incubation mainly functions to conserve egg weight by preventing water loss.

The young measure 10-17 inches upon hatching, and reach sexual maturity at 3-4 years of age, by which time they are approximately 3 feet in length.

Economic Importance

Ball pythons are heavily utilized as food by people throughout much of their range, and are harvested for the leather trade as well.  Until captive bred stock became widely available, huge numbers were collected for the pet trade and exported to Europe, Japan and the USA.

Miscellaneous

The common name of this snake is derived from its habit of coiling into a tight ball, with the head hidden within the center, when threatened.  Once so situated, it is difficult to uncoil the snake, and it will remain so even if rolled about (not recommended!).  However, some ball pythons surprise attackers (and annoying keepers!) by biting savagely when disturbed.  Actually, a number of other pythons and unrelated snakes utilize a coiled defensive posture, but in none is it so well developed as the ball python.

 

An extensive CITES-generated study of ball python populations and management in Ghana is posted at:

http://www.stevegorzulapresents.com/study_royal_python_ghana.pdf

 

 

The 60+ species of sea snakes – brightly colored, highly venomous relatives of the cobras, mambas and coral snakes – are little studied and not often seen in zoos.  I was fortunate enough to have worked with yellow-bellied sea snakes (Pelamis platurus) at the Bronx Zoo, but the species is no longer exhibited there (perhaps something to do with the preferred diet of live moray and American eels?).   If you have the opportunity to visit a zoo that keeps sea snakes, by all means do so – you will not be disappointed.

How Marine Snakes Find Fresh Water

A recent Physiological and Biochemical Zoology article, written by noted herpetologist Harvey Lillywhite, dispels a popular belief concerning marine snakes.   Sea snakes, it seems, do not use special glands to extract salt from sea water, thus rendering it drinkable.  These glands remove excess salt from the bloodstream, but the snakes can drink only fresh or very dilute sea water.

Research focusing on the black-banded sea krait (Laticauda semifasciata) showed that the snakes obtain all their drinking water from fresh water springs (sea kraits leave the water on occasion), and refuse to drink sea water even when dehydrated.  The majority of other sea snakes, which do not travel overland, are presumed to drink from the surface layer of fresh water that develops on the ocean when it rains.  Indeed, sea snakes reach their greatest diversity in regions with heavy rainfall, and sea kraits are most common near fresh water spring outflows.

Notes on Marine Reptiles in North America

The study seems to raise questions as to the drinking habits of other marine reptiles, such as sea turtles.  It brought to my mind time spent observing mangrove salt marsh snakes (Nerodia clarkii compressicauda) in Florida – that particular snake lives largely in salt water, but periodically travels to nearby fresh water swamps to drink.

At the mouth of the Nissequogue River on Long Island, NY, I encountered a population of snapping turtles (Chelydra serpentina) that have been documented as having salt-excreting glands not possessed by snapping turtles living further upstream in the same river.  I’ll soon review an article written on the turtles in that habitat, with a view towards reconciling it with this surprising new information.

You can read more about the natural history of sea snakes and sea kraits at the web site of the Chicago Field Museum:

http://www.fieldmuseum.org/aquaticsnakes/true_sea.html

Image referenced at Wikipedia, http://en.wikipedia.org/wiki/Image:Banded_Sea_Snake-jonhanson.jpg, and originally posted by Jon Hanson on FlickR.