Two species of reptiles which, with the caimans, belong to a family closely related to the crocodiles. Alligators and crocodiles look extremely alike: the main distinguishing feature is the teeth. In a crocodile the teeth in the upper and lower jaws are in line, but in the alligator, when its mouth is shut, the upper teeth lie outside the lower. In both animals the fourth lower tooth on each side is perceptibly larger than the rest: in the crocodile this tooth fits into a notch in the upper jaw and is visible when the mouth is closed, whereas in the alligator, with the lower teeth inside the upper, it fits into a pit in the upper jaw and is lost to sight when the mouth is shut. In addition, the alligator’s head is broader and shorter and the snout consequently blunter. Otherwise, especially in their adaptations to an aquatic life, alligators are very similar to crocodiles.
One of the two species is found in North America, the other in China. The Chinese alligator averages a little over 4 ft in length and has no webs between the toes. The American alligator is much larger, with a maximum recorded length of 19 ft 2 in. This length, however, is seldom attained nowadays because the American alligator has been killed off for the sake of its skin; whenever there is intense persecution of an animal the larger ones are quickly eliminated and the average size of the remainder drops slowly as persecution proceeds.
It is sheer accident that two such similar reptiles as the alligator and the crocodile should so early have been given different common names. The reason is that when the Spanish seamen, who had presumably no knowledge of crocodiles, first saw large reptiles in the Central American rivers, they spoke of them as lizards – el largato in Spanish. The English sailors who followed later adopted the Spanish name but ran the two into one to make «allagarter» – which was later further corrupted to «alligator».
Long lazy life
Alligators are more sluggish than crocodiles; this may possibly have an effect on their longevity, for there are records of alligators having lived more than 50 years. They spend most of their time basking on the banks of rivers.
The American alligator is restricted to the south-eastern United States and does not penetrate further north than latitude 35. The Chinese alligator is found only in the Yangtse River basin.
Alligators’ food changes with age. The young feed on insects and on those crustaceans generally known as freshwater shrimps. As they grow older they eat frogs, snakes and fish; mature adults live mainly on fish but will catch muskrats and small mammals that go down to the water’s edge to drink. They also take a certain amount of waterfowl. Very large alligators may occasionally pull large mammals such as deer or cows down into the water and drown them.
Alligator builds a nest
It seems that the female alligator plays the more active role in courtship and territorial defence. The males apparently spend much of the breeding season quarrelling among themselves, roaring and fighting and injuring each other. The roaring attracts the females to the males, as does a musky secretion from glands in the male’s throat and cloaca. Courtship takes place usually at night, the pair swimming round faster and faster and finally mating in the water with jaws interlocked and the male’s body arched over the female’s.
A large nest-mound is made for the reception of the eggs. The female scoops up mud in her jaws and mixes it with decaying vegetation; the mixture is then deposited on the nest site until a mound 3 ft high is made. The eggs are hard-shelled and number 15-80; they are laid in a depression in the top of the mound and covered with more vegetation. The female remains by the eggs until they hatch 2-3 months later, incubated by the heat of the nest’s rotting vegetation.
The hatchling alligators peep loudly and the female removes the layer of vegetation over the nest to help them escape. Baby alligators are 8 in long when first hatched and grow 1 ft a year, reaching maturity at 6 years.
The biter bitten
Young alligators fall an easy prey to carnivorous fish, birds and mammals, and at all stages of growth they are attacked and eaten by larger alligators. This natural predation was, in the past, just sufficient to keep the numbers of alligator populations steady. Then came the fashion for making women’s shoes, handbags and other ornamental goods of alligator skin. So long as these articles remain in fashion and command a high price, men will be prepared to risk both the imprisonment consequent on the laws passed to protect alligators and the attacks of the alligators themselves.
There is also another commercial interest, detrimental both to the alligator and to the fashion industry. For, while the fashion for skins from larger individuals shows no sign of abating, a fashion for alligator pets also persists – though it may have dropped in intensity since its inception. Baby alligators are still being netted in large numbers for the pet shops, but – as so commonly happens with pets taken from the wild – not all those caught are eventually sold. Of a consignment of 1,000 hatchlings that reached New York City in 1967, 200 were already dead and putrefying, and many others were in a sorry condition and unlikely to survive.
In addition to persecution, land drainage has seriously affected the numbers of the American alligator. The Chinese alligator is an even worse case. Its flesh is eaten and the various parts of its body are used as charms, aphrodisiacs and for their supposed medicinal properties. The New York Zoological Park has recently announced plans to try and breed the Chinese alligator and so protect it from complete extermination.
Pets down the drain
The fashion for alligator pets has its disadvantages for owners as well as the alligator populations. Even setting aside the largest recorded lengths for the American species of 19 ft upwards, it still achieves too large a size to be convenient in the modern flat, and people who invest in an alligator often find it necessary to dispose of it. Zoos have proved unable to deal with the quantity offered them – Brookfield Zoo near Chicago has built up an enormous herd from unwanted pets – and it is widely said that unfortunate alligators are disposed of in such a way that they end up in the sewers. One result of this is that every now and then, despite official denials, reports have appeared in the press to the effect that the sewers of New York are teeming with alligators that prey on the rats and terrorise the sewermen.