Watersnake Hunting

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05/30/2020: A northern water snake (Nerodia sipedon) with a stumpy tail chooses a perfect basking spot in the middle of a stream. Water snakes have a generalist diet and feed on a variety of aquatic and terrestrial prey, including fish, salamanders, frogs, small mammals, mollusks, earthworms, leeches, insects, and crayfish.

Photographed in situ [1], Columbia, Missouri

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4/04/2021: Young northern water snakes are among the most abundant snakes at the start of the spring. In Missouri, females give birth in the fall, so the now 6-7 month old juveniles emerge in mass to feed on frogs and fish after the long winter hiatus.

Photographed after slight disturbance [2]

Basking at sunset; photographed after slight disturbance [2]
Filmed in situ [1]

Two years ago back in my hometown, Temple, TX, I found another water snake (Nerodia erythrogaster transversa) hunting fish in a muddy stream. The snake whipped along the water’s surface back and forth with its mouth agape, while pink-sided fish spurted out from the ripples. Each time the snake’s head stopped moving, its body extended forward in a motion perpendicular to the imminent lunge. This circular movement is likely used to herd fish into a position where the snake can intercept them. As the snake turns, its head also dips all the way to the tip of the tail, which is moving in the opposite direction. Fish that happen to swim near the snake’s tail tip end up recoiling directly into the line of fire where the snake’s mouth is. So, by undulating in an exaggerated S-shape, water snakes take advantage of this stereotyped escape behavior in fish, termed a “C-start.” Looking closely at the footage, this sometimes occurs just before a fish wildly splashes and jumps out of the way. If only the water wasn’t so murky!

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Typical ‘C-start’ startle behavior in a northern pike (Esox lucius)Liu & Hale 2014

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