Intraseasonal Change in Caloric Content of Some Freshwater Invertebrates
1971
Wissing, Thomas E. | Hasler, Arthur D.
Intraseasonal changes in caloric contents of planktonic cladocerans (Daphnia spp. and Leptodora kindtii), amphipods (Hyalella azteca), and chironomid larvae (primarily Glyptotendipes sp.) were studied in 1968. Mid—summer decreases of 823, 2117, and 422 g—cal/g dry weight were observed in the Daphnia, L. kindtii, and H. azteca, respectively. Calorica content of Daphnia increased again during August and early September. The energy content of chironomid larvae increased steadily during June and July and then declined. The low value (4899 g—cal/g dry weight) occurred on 9 September. Variation in energy content of the Daphnia appeared to be related to known changes in population numbers. The influence of significant changes in caloric contents of food organisms on the daily ration of predator fish species is discussed.
显示更多 [+] 显示较少 [-]