Jun 29, 2019
The cottonmouth is a pit viper frequently seen by the marsh in Hudsonville.
Cottonmouths, Agkistrodon piscivorus, display large broadbands and they turn almost solid black as they age. The belly has irregular blotches and the underside of the tail is black. The western cottonmouth is the one found in Hollysprings, it is one of the 5 sub-species of the South East. (A. p. leucostoma). The typical size is about 3 feet long, but the large ones can be up to 6 feet. One of the distinctive characters is a black line from the eye to the back of the lower jaw. Its body shape is heavy to very heavy in some individuals. it can be called water mocassin or even cottonmouth mocassin by tradition. One fact that I used to associate to local folklore and therefore give little credence to is that cottonmouths can actually bite underwater.
Cottonmouths are rather associated with river swamps than with the rivers themselves. They are prevalent in isolated wetlands, especially when such habitats are surrounded by swampy habitat or heavy vegetation, which is the case at the head of the Cold Water river. They will hibernate during winter, in retreats which are away from the swamp, we see them in October on the paths in the woods on the western slopes. During the active season, cottonmouths move at night or during the day. They will hunt after dark in hot days. One can find them coiled on a stump or along a fallen log. On sunny days of fall they may be found on the lower branches of a tree. I personally have never seen any in a tree.
While they have been named after their fish diet (piscivorus), they are opportunistic predators and eat a wide assortment of preys. They can ambush or actively hunt. They will eat rodents, birds, fish, frogs, turtles, other snakes.
The mating period is in spring, apparently there also can be a fall mating period. Males will ‘fight’ other competing males in ‘combat dances’ to win the privilege of mating. Litters of 7 babies in average are born late summer or early fall. Baby cottonmouths are lighter in color and more brightly banded. They display a greenish tail tip. The baby cottonmouths can be mistaken for copperheads.
The very large cottonmouth below (I estimate 5 feet long ) fought with one of the dogs and stood its ground, keeping its mouth open to deter the opponent. I could finally hold the dog back, it had been bitten in the chest. I carefully checked the snake looking for wounds as there was blood in its mouth. There was not even a scratch. It finally calmed down and went its way back in the swamp. Behavioral research has demonstrated that the species is not agressive toward humans, cottonmouths are mainly defensive in nature. These studies have also shown that most cottonmouths will not bite a person unless they are being picked up.
They are not threatened as a species, they can be locally extirpated, especially if a new road separates the foraging area to the hibernation quarters.
The venom of cottonmouths destroys blood cells and has anticoagulant properties. Deaths have resulted from their bites, however nearly all victims that received proper medical attention survived.