Egg population dynamics of naturally spawning dace,Leuciscus leuciscus (L.) |
| |
Authors: | Chris A Mills |
| |
Institution: | (1) Freshwater Biological Association, River Laboratory, East Stoke, Wareham, Dorset, BH20 6BB, UK |
| |
Abstract: | Synopsis Survival of dace eggs in a chalkstream was 8.6 to 21.8% from spawning to hatching. The proportion of dead eggs in samples rose from 4.9% at the end of spawning to 59% after 13 days. The combined number of dead eggs, live eggs and the empty shells of eggs after hatching also began a steady decline soon after the end of spawning. Egg drift was estimated to be 2.0% of the initial egg population. Laboratory studies and field population estimates indicated that macroinvertebrates were capable of eating large numbers of dead eggs but much smaller numbers of live ones. A large part of the fall in egg numbers was accounted for by egg decomposition. There was a close relationship between the percentage of surviving eggs and substrate composition with poor survival in areas of high silt and low gravel content. |
| |
Keywords: | Current Decomposition Depth Drift Model Predation Silt Substrate composition Temperature |
本文献已被 SpringerLink 等数据库收录! |
|