Crocodiles: one of the last archosaurs

There are twenty-three species of crocodiles left in the world today, the latest in a large and diverse group of reptiles whose origins date back some 250 million years. The tropics in what we know as the New and Old worlds have crocodiles in their various shapes and forms, but all of these species are endangered and vulnerable to extinction. Crocodilians are one of the main branches of the subclass of reptiles called Archosauria, sometimes referred to as “ruling reptiles” due to the dominance of these creatures in terrestrial habitats during the Mesozoic Era. As one of the main branches of the Archosauria family tree, crocodyliforms (the term used to refer to all kinds of crocodiles, alligators, alligators, and gavials), share a common ancestor with flying reptiles and dinosaurs. The only other surviving members of the Archosaur family alive today are birds.

Alligators, crocodiles, gharials and alligators

Of the twenty-three extant species, only thirteen are true crocodilians, the other members of this group being the broad-snouted alligators, alligators (restricted to the New World), and narrow-snouted gharials (restricted to the Old World). Although several individual species have extensive ranges, all types of crocodyliforms are covered by CITES (the convention on international trade in endangered species, although certain species are more threatened than other species).

The problem is that these creatures do not have many allies among humans. All of these animals, even some of the smaller species, such as the broad-nosed crocodile (osteolaemus tetrapis) of central and western Africa, which rarely exceeds six feet in length, is capable of inflicting very serious injuries. Attacks on children are rare and there have been reports of deaths. Large crocodyliforms such as the American alligator (Alligator mississippiensis) have been known to attack people, and many domestic cats and dogs are eaten by these reptiles in Florida each year. However, man has had a devastating effect on alligator populations in the past. In the period from 1880 to 1894 it has been estimated that some 2.25 million were slaughtered in the wild, many of them for their valuable skins.

The largest species of true crocodiles that can exceed twelve feet or more in length are known to be man-eaters. The saltwater or estuarine crocodile (Crocodylus porosus) is responsible for a number of fatal attacks each year. Nile crocodile (Crocodylus niloticus) has a formidable reputation, as does Asia’s Mugger crocodile – Crocodylus palustris. There are often conflicts of interest between local fishermen and villagers and a resident crocodile population, especially as human settlements have moved into areas bordering the swamps as the human population has grown. It’s the crocodiles that end up being euthanized, people, and these apex predators don’t get along.

The underside skin of many types of crocodiles has been processed for thousands of years, producing extremely soft and luxurious leather. Crocodiles are hunted for sport and there is much intensive poaching of young animals for the pet trade. It has been estimated that more than a million young crocodiles are exported from South America each year for the pet trade. Pollution has affected various crocodile populations, as has the loss of suitable habitat. The Indian gharial is perhaps the rarest of all crocodyliforms, numbering only about two hundred wild specimens. Several adult animals have succumbed to the disease, perhaps to chemical poisoning due to contamination of the river, and the breeding population in the wild in India has decreased significantly. The gharial is now listed as “critically endangered” under CITES. These magnificent fish eaters nearly became extinct in the wild in the 1970s, but a captive breeding and release program brought this species back from the brink of extinction. However, attempts to reintroduce individuals to the wild have been hampered by the lack of suitable range available for gharials. There simply are not enough suitable release sites available.

Unfortunately, many people find it hard to love these scaly monsters, with their fearsome and in many cases well-deserved reputation as man-eaters. However, it’s not just the cute and cuddly pandas that need our protection. In fact, it could be argued that money spent trying to maintain panda populations can be better spent trying to protect crocodile species around the world.

Why crocodiles over pandas?

Crocodiles are certainly not cute, they lack the fur of mammals, but they play a bigger role in food chains than China’s giant panda, for example. The American alligator, when fully mature, eats many rodents and thus helps keep pest numbers down. The American alligator digs out ponds in Florida’s swamps and these “alligator holes” provide an oasis of water during droughts in the region. These sites can support a wide variety of indigenous flora and fauna, all of which rely on adult alligators to dig the ponds in the first place.

All members of the Crocodyliforms are covered by CITES regulations. For some species, trade in any product produced from animals, bones, skin, meat is prohibited. Population numbers are so low that they make any trade a real threat to the survival of the species. Some crocodile products can be traded, but this is done under the strict supervision of CITES.

Visiting Schools Teaching about Crocodile Preservation

When we visit schools that work with young students aged five and up, we use the example of crocodiles to explain extinction. We compare crocodiles to those other reptilian members of the Archosauria, the dinosaurs, and try to overcome the need to protect all animals and their habitats as best we can. When asked to name an animal in danger of extinction due to the activities of our species, students tend to name mammals as examples. However, we’re doing our best to help convince future conservationists that even unloved scaly monsters like crocodiles need our protection, too.