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USGS · 5223690

Estimating prey size and number in crayfish-eating snakes, genus Regina

J.S. Godley·R.W. McDiarmid·N.N. Rojas
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Abstract

Snakes of the genus Regina feed almost exclusively on crayfish. The paired, symmetrical gastroliths of crayfish are not digested and are detectable from x-rays of the snake. Gastrolith length is directly proportional to carapace length and can be obtained from x-rays. Carapace length can be converted to kcal of ingested energy. Using these relationships and repeated captures of radio-telemetered Regina, estimates of food consumption and energy intake by freeliving snakes are feasible. New information on prey selectivity, feeding behavior, and predator-prey size relations in Regina grahami and R. septemvittata are presented and compared with similar data for other snakes.

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J.S. Godley, R.W. McDiarmid, N.N. Rojas. 1984. Estimating prey size and number in crayfish-eating snakes, genus Regina. https://pubs.usgs.gov/publication/5223690

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