Nature. Migration of Blowing Vipers.

Waikato Times, Volume XXV, Issue 2057, 12 September 1885, Page 6 (Supplement)

Nature. Migration of Blowing Vipers.

BY C. I'EW SEISS.

A few seasons ago, a narrow sandy island on the coast of New Jersey was overrun with countless numbers of the common toad (Bufo lentigiriosm Americanm). The toad is generally of crepuscular habits, except during cloudy and rainy weather, but here they were met with, out in search of food, at all hours of the day, even beneath the hot glare of the noonday sun. It may be that, bad they all waited until the cool of the evening to hunt for their insect picy, many of the weaker and less active toads would have been supperless. So, by hunting bolh by day and night, they were able to secure both diurnal and nocturnal insects. Over two hundred toads were counted in a short stroll between four and five o'clock in the afternoon of a July day. At this period there were no snakes of any kind to be met with on the island. That a few did exist I do not doubt, but they were not observed. Now, this narrow island is separated from the mainland by a small bay or thoroughfare, which is perhaps over a quarter of a mile wide at its narrowest portion. The vegetation on the [island consisted of little else than rank grass, stunted cedar?, and pines. In the season following the one above noted the toads were again innumerable, but, what was startling, "blowing vipers" (Wterodon platyrhintu) were numerous also. They were observed in nearly every part of the island, and were seen pursuing, capturing, and swallowing the toads, as though bent on their extermination, Sometimes a toad would endeavour to escape by quickly burrowing into the sand, but the snake, having marked the spot where the toad disappeared, would force its head, with shovel-like snout, into the sand, seize the unfortunate toad, drag it from its hiding place, and swallow it. What was the cause of this sudden appearance and number of snakes? They made their appearance in early summer, when the young Heterodont were not yet out of the egg, and it requires several months of growth before they are capable of mastering an averaged sized toad. Did they come from the mainland by swimming across the bay, whioh at its narrowest part is a quarter of a mile wide ? This would seem like a great undertaking for a non-aquatic speoies, but, nevertheless, it is the only way in which they oonld have oome. A migration of snakes has never before come under my notice, and yet I must consider this sudden appearance of " blowing vipers " as suoh. It is highly probable that food became scarce in their old haunts, and they migrated to the island in hopes of finding food more plentiful. It is not probable that their sense of smell is so highly developed as to have soented the toads from suoh a distance, and that they were quitting their old home with the certain knowledge that food in abundanoej awaited them on this sandy island. In the summer following this migration, toads were not numerous, and only a few snakes were observed; and such, I learn, has been the case for the two or three intervening years since then. Of course, great numbers of the snakes were killed by man ; not beoause they were thought to be poisonous, for this speoies is here generally and correctly understood to be perfeotly harmless, nor always for mere wontonneu, bat from the belief that in destroying the snakes they were preserving the lives of many toads, whioh were benefioial to man, inasmuch as they fed upon mosquitoes. Now, the. tormenting misqmto (Cultx damnotiu) is by far too small a spceies of game for the toad. I have examined the contents of the stomachs of several maritime toads' but failed to find mosquitoes. Very young toads, wbioh have just left the water and the tadpole stage, do feed upon minute inseots, tuoh as gnats, ants, aphides, do., but I refer only to the mature animals.