Rach, J. J., and Dawson, V. K., 1991, Aspects of the life history of the calico
crayfish with special reference to egg hatching success: The Progressive Fish
Culturist, v. 53, no. 3, p. 141-145.

Abstract

Life history data were collected on adult ( greater than or equal to 25 mm carapace
length) female calico crayfish (Orconectes immunis ) in conjunction with an
egg-hatching study during 1986-1988. Eggs stripped from 10 females in October
1986 and 10 females in September 1987 were pooled each year and hatching
success was monitored for samples of 100 eggs placed in each of eight diluter
aquaria at 12 degree C. In fall 1987, berried calico crayfish were cultured at 12, 25,
and 30 degree C and hatching was monitored. Data on length, weight, and number
of eggs produced were collected for 28 females in September 1987 and 36 females
in April 1988. An additional 456 female crayfish were checked for the presence of
eggs. Hatching success was 86% in 1986 and 89% in 1987. The eggs on berried
females held at 12 degree C started to hatch within 33 d. At 25 degree C, hatching
started within 10 d. At 30 degree C, no hatching occurred, the eggs became orange
(indicating death), and most of the eggs later developed fungal infections.

Keywords

eggs-/ hatching-/ life-history/ temperature-effects/ fish-ponds/ Orconectes-immunis/
females-/ USA,- Wisconsin/ freshwater-crustaceans.