Thursday 20 October 2011

Crocodiles of the World

As a birthday treat to myself this year, on the nineteenth of September I made a trip to Crocodiles of the World in Crawley, a town just outside of Oxford in the Cotswold Hills. When I first heard about this place, about a month before, I was so excited to visit that I booked a place on a private tour for that day, knowing that I’d be passing through the area en route back to London from Gloucestershire. It’s a small facility that houses twelve species of crocodilian and a small number of other reptiles, but some of the species are found in few other captive collections. A breeding pair is sought for each species, and some are already breeding in the very short history of the centre, which only opened to the public in February this year. The centre exists due to the work of Shaun Foggett, known to viewers of a UK Channel 5 documentary as ‘Croc Man’, and he deserves high praise for the work he is doing to help conserve and educate the public about crocodilians.

All photos below were taken by Mo Hassan at Crocodiles of the World, Oxfordshire, September 2011.

Siamese crocodile
Crocodylus siamensis Schneider, 1801
Crocodylidae; Crocodilia; Sauropsida; Chordata

The Siamese crocodile is one of the rarest crocodiles in the world, restricted to the Indochinese Peninsula, Borneo, and possibly Java. It is a relatively small crocodile that coexists with its much larger relative, the saltwater crocodile (C. porosus) across its range, and indeed they occasionally hybridise both in the wild and in captivity. This dilution of the gene pool is a severe threat to the Siamese crocodile, as well as hunting for its skin, as in all crocodilians.

Dwarf crocodile (one-year-old juvenile above, two-day-old hatchling below)
Osteolaemus tetraspis Cope, 1861
Crocodylidae; Crocodilia; Sauropsida; Chordata

As its name suggests, the dwarf crocodile is the smallest crocodile, and is native to west and central Africa. It too coexists with a larger, more well known species, the Nile crocodile, as well as the slender-snouted crocodile (Mecistops cataphractus), all of which occupy different niches so they do not suffer from interspecific competition. Dwarf crocodiles eat fish and crustaceans, not taking larger prey. As you can see, they are breeding well at the centre.

American alligator
Alligator mississippiensis (Daudin, 1802)
Alligatoridae; Crocodilia; Sauropsida; Chordata

American alligators need no introduction, so no introduction shall I give. Notice the maloccluded jaw on this specimen.

Cuban crocodile
Crocodylus rhombifer Cuvier, 1807
Crocodylidae; Crocodilia; Sauropsida; Chordata

The Cuban crocodile is a lightly built, critically endangered species of crocodile restricted in distribution to parts of Cuba and nearby small islands. It was previously more widely distributed on the island, and fossil remains have been found on other Caribbean islands. It is easily distinguished from other crocs by its ‘pebbled’ appearance and relatively long legs, which suggest it is more terrestrial, and it is. It shares its range with the American crocodile (Crocodylus acutus), but doesn’t clash due to differences in habitat and ecology.

Black caiman
Melanosuchus niger Spix, 1825
Alligatoridae; Crocodilia; Sauropsida; Chordata

The largest of the six species of caiman, the black caiman hails from the river Amazon and its tributaries. It can be told apart from the other, smaller caimans by the presence of black blotches on its lower jaw and its darker coloration. When adult, the black caiman is an apex predator, eating the other large animals found in its ecosystem, including capybara, anaconda, and tapir, and are immune from attack from jaguars due to their size.

Juvenile Nile crocodiles
Crocodylus niloticus (Laurenti, 1768)
Crocodylidae; Crocodilia; Sauropsida; Chordata

This is the beast that dominates much of Africa and Madagascar, unless the studies that have shown there to be two species of African Crocodylus prove to be correct. The subspecies C. n. suchus from western and central Africa, and historically from the lower reaches of the Nile, has been identified in various studies as perhaps forming a species in its own right. Part of the basis for this finding has been the study of DNA from mummified crocodiles from Egypt and the Sudan. I’ll personally wait until there have been more studies, especially morphological ones.

Schneider’s dwarf caiman
Paleosuchus trigonatus (Schneider, 1801)
Alligatoridae; Crocodilia; Sauropsida; Chordata

Also known as the smooth-fronted caiman, this is a small little-known species from northern parts of South America in the Amazon and Orinoco rivers.

Cuvier’s dwarf caiman
Paleosuchus palpebrosus (Cuvier, 1807)
Alligatoridae; Crocodilia; Sauropsida; Chordata

Another tiny crocodilian, in fact, the tiniest, at no more than one and a half metres in length. It is found in lowland tropical parts of South America, mostly in fast-flowing streams. At the time I visited Crocodiles of the World, the female Cuvier’s dwarf caiman had just laid a nest of eggs.

Broad-snouted caiman
Caiman latirostris (Daudin, 1801)
Alligatoridae; Crocodilia; Sauropsida; Chordata

The broad-snouted caiman is in the same genus as the spectacled caiman (C. crocodilus) and the yacare caiman (C. yacare), and is found in southern Brazil and neighbouring countries in marshes, swamps, mangroves, and other slow-moving water bodies. It is intermediate in size between the larger black and spectacled caimans and the smaller dwarf caimans.

The other species held at Crocodiles of the World are the Morelet’s crocodile (Crocodylus moreletii) from southern Mexico and Central America, the Chinese alligator (Alligator sinensis), and the spectacled caiman. There are also a few kinds of freshwater turtle, a Meller’s chameleon (Trioceros melleri, and two of the longest monitor lizards.

Crocodile monitor
Varanus salvadorii Peters & Doria, 1878
Varanidae; Squamata; Sauropsida; Chordata

The crocodile monitor from New Guinea reaches lengths of almost two and a half metres, truly earning its name. It’s an arboreal species and uses its prehensile tail to help with gripping to tree branches. It is the apex predator of New Guinea (despite there being an endemic crocodile, Crocodylus novaeguineae, and even saltwater crocodiles on the coasts), bringing down large mammals, like its heavier relative, the Komodo dragon (Varanus komodoensis) does.

Water monitor
Varanus salvator (Laurenti, 1768)
Varanidae; Squamata; Sauropsida; Chordata

The water monitor was previously believed to live in much of southeast Asia, but several former subspecies have been separated, including three Philippine species, from the water monitor proper. It’s another very large monitor, among the world’s longest, and like the crocodile monitor, can take large prey.


traumador said...

Love that shot Schneider’s dwarf caiman. He looks like he wants to talk to you.

A very cool looking facility.

I discovered Hong Kong has a very famous Saltie in captivity that was caught in the swamps 5 blocks from where I live. Not sure how I feel about sitting by the water's edge now looking for Kingfishers...

davidmaas said...

Fantastic stuff, thanks!

Jae Kay said...

1. I'm very jealous

2. That picture of the paleosuchus trigonatus is tremendous!

3. That place sure beats the Thai crocodile centre I went to, which consisted mainly a bunch of deep pits full of crocodiles that managed to be both cruel and utterly pointless as no one could bloody seem them! I may have to visit...