Utilization of Crawfishes by Cold-Blooded Vertebrates in the Eastern United States

Abstract

Quantitatively crawfishes have been little studied. A few species, however, have been shown to exist in enormous numbers in their optimum habitats. Davis and Weibe (1930) reported the removal of over 500 pounds of unidentified crawfishes from a pond in Iowa slightly over an acre in extent which produced at the same time 7,581 fingerling black bass. Creaser (1934) found mixed Cambarus bartoni and C. robustus in Pine Brook of the Raquette River watershed in New York at the rate of 4,044 individuals per mile of stream (about 16 pounds per acre) which he stated was a production greater than that of the fishes present in the same brook. Surber (1936) reported unidentified crawfishes in a stream in Virginia at their peak of annual production in August and September at the rate of 3.1 individuals per square foot of bottom, or about 135,036 per acre. Langlois (1936) indicated Cambarus rusticus production in fish hatcheries in Ohio averaging about 850 pounds per acre with a peak of 1,587 pounds per acre in one pond in addition to the bass crop. Wickliff (1940) recorded peak production of unidentified crawfishes in stream riffles in Ohio between May and September: in a sand and riffle he found 6,250 individuals per acre (27 pounds per acre); in a gravel riffle in May, three per square foot or 130,680 per acre (1,176 pounds per acre); and, in a riffle in August four per square foot or 174,240 per acre (523 pounds per acre). He depopulated the rubble riffle and two days later it yielded at the rate of 6,070 crawfishes per acre, evidently being repopulated from adjacent parts of the stream. In the Cornell Experimental Fish Hatchery at Ithaca, New York, Tack (1941) recorded production of Orconectes immunis immunis at the rate of from 36 to 255 pounds per acre in different