The Snakes of Europe

by George Albert Boulenger

The enormous mortality for which snake-bite is responsible in India is well known. Statistics establish the fact that an average of 20,000 human lives are thus lost annually: 24,264 is the official return for 1911. In Australia, where highly poisonous snakes of various genera and species abound, the fatal cases are likewise very numerous, though less in proportion than in South America, and no doubt also in Africa. In the small island of Martinique, the Fer-de-Lance, Lachesis lanceolatus, causes every year the death of about 100 human creatures. Though numerous in species, the poisonous snakes of Ceylon cause a comparatively small mortality—200 per annum.

Modern research has resulted in the discovery of the only effective antidote for snake-venom intoxication: the serotherapic treatment. An animal that has been treated over a length of time with the venom of a poisonous snake, such as a Cobra, yields a serum which is antitoxic towards that venom; but the great difficulty resides in the specificity of the different poisons, which often renders the use of the serum ineffective in countries like India and Australia, where several kinds of poisonous snakes occur in the same district (see above, p. [67]). In India, where a special laboratory has been established for the supply of antivenine, at the Central Institute of Kasauli, it has been found impossible to obtain any venoms but those of the Cobra and Russell’s Viper in sufficient quantity to immunize animals, and thus produce the serum necessary for dealing with the bite of the King Cobra, the Krait, and the Echis Viper.

In Pondicherry the French Government places annually a sum of 200 rupees at the disposal of the director of the hospital for obtaining Cobra poison, the snakes, to be brought alive, being paid for to the natives at the rate of half a rupee to one rupee each, according to size and condition. Six hundred and fifty-three specimens were thus purchased in less than two years (1901-1903). The poison is utilized for the preparation of Calmette’s antivenine, which, as we have said above, is only effective against cobra poison, and, unfortunately, useless for the cure of bites from other species.

In Brazil, where the number of accidents is estimated at 19,200 per annum, and that of fatal cases at 4,800, over 2,000 snakes (Lachesis and Crotalus) are brought annually to the Serotherapic Institute of Batantan, in the province of S. Paolo, for the preparation of the antitoxic serum, which is given in exchange for the snakes. According to the latest report of the Institute (1911), two serums are distributed: the anti-crotaline (for Rattlesnake bite) and the anti-bothropine (for Lachesis bite); the third, the anti-elapine (for Coral-snake bite), is in course of preparation.

In many countries a premium has for years been paid for the heads of poisonous snakes, and has led to the destruction of enormous numbers of them, without, however, resulting in a very appreciable diminution of the dangerous reptiles. More than £12,000 has been spent for this purpose in India alone; the numbers destroyed in 1885 and 1886 throughout British India amount to 420,044 and 417,596 respectively. About forty years ago the Governor of St. Lucia offered a reward of 4d. for every Fer-de-Lance’s head. But the negroes caught them alive and bred families of snakes for the sake of the reward, and thereby made what was for them a little fortune, these snakes bringing forth up to sixty young at a birth. The reward had to be abolished very soon.

Now about the Vipers of Europe, the only really dangerous snakes of this part of the world.

Although the Adder, Vipera berus, is quite common in many parts of England and Scotland, accidents caused by its bite are rarely heard of, and cases of death are few and far between. It is not so, however, on the Continent, where the same species, and especially its close ally, the more southern V. aspis, are responsible for many fatalities, due no doubt to the more virulent action of the venom in a warmer climate.

In the French Departments Loire-Inférieure and Vendée, where these snakes are very plentiful, three or four cases of death are reported annually. From 1860 to 1868, 370 serious accidents to man have been carefully recorded, 53 ending in death, not only in the case of children, but also of adults of all ages, in 10 cases within one to twenty-four hours. In the Puy-de-Dôme cases of death are of frequent occurrence. In Germany and in Switzerland, 12 or 13 per cent. of the cases on record have ended fatally. Instances of death from the bite of the south-eastern V. ammodytes are also not infrequent. On the other hand, the bite of V. ursinii, which is but seldom inflicted, is not known to have ever resulted in death.

It must be borne in mind that accidents are much more frequent in districts where the poorer classes are in the habit of going about barefoot.

Anyhow, it is certain that Vipers are a serious danger in many parts of Europe, not only to man, but also to horses, cattle, and dogs. And it is not surprising that efforts have been made to reduce their numbers. The most efficacious means, besides the protection of certain animals and birds which feed on Vipers, appeared to be the institution of premiums to be paid for the heads of the dangerous snakes. By offering 21⁄2d. per head, 500,000 Vipers (V. aspis) were destroyed from 1864 to 1890 in three French departments, Haute-Saône, Doubs, and Jura, and in one district (Chaumont) of the Haute-Marne 57,045 were killed from 1856 to 1861; this gives an idea of the extraordinary abundance of these snakes in some parts of France. In the Puy-de-Dôme the premium was fixed for a time at 5d., and one man managed to destroy in the course of seven years 9,175 Vipers (V. berus and V. aspis). A woman in the Deux-Sèvres has made a living for many years by catching Vipers, the heads of which were paid to her at the rate of 5d. each. The average number of her captures amounted to 2,062 per annum (mostly V. aspis). Around Oesnitz in Saxony, 2,140 V. berus were killed in 1889, and 3,335 in 1890. In a single district in Southern Styria the heads of 4,197 V. berus and 7,381 V. ammodytes were sent in for the reward in the course of two years (1892, 1893).