0+ perch predation on 0+ bream: a case study in a eutrophic gravel pit lake
0+ perch predation on 0+ bream: a case study in a eutrophic gravel pit lake
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0 鲈鱼捕食 0 鳊鱼：富营养化砾石坑湖的案例研究
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
J. Borcherding
中科院分区：
文献类型：
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作者：
P. Beeck;S. Tauber;S. Kiel;J. Borcherding
1.我们研究了0+鱼类在富营养化的砾石坑湖，其中捕食的0+欧亚鲈鱼对其他0+鱼类被怀疑影响鲈鱼的生长和鱼类群落的结构，对湖泊食物网的影响。2.成鱼群落以鲈类为主，0+鱼群落以鲈类和鲷类为主。5月至8月底，鲷的总长度为80毫米，在夏季逐渐减少，并在秋季完全消失。胃分析显示0+鲈鱼≥28 mm以0+鲷为食。3.最初的单峰队列0+鲈鱼逐渐扩大，并成为双峰到7月底。较大的食鱼队列中的鱼比较小的消耗浮游动物的鱼（0.6 mm天-1）生长得更快（1.4 mm天-1）。虽然这两个队列的个人后来消费浮游动物和增长率相似（0.5毫米天-1），只有鲈鱼的大队列（平均TL 125毫米）被发现到10月中旬。对食物的种内竞争或老鲈鱼的同类相食可能导致了较小鲈鱼的消失。4.早期的快速增长0+鲈鱼的食鱼显然导致0+鲷的消失，在生长季节结束和雄性鲈鱼的早熟成熟。在其他研究中的结果相反，这些大0+鲈鱼，从而避免了少年瓶颈切换到piscivory早期在其个体发育。5.本研究的观察结果表明，早期piscivory的0+鲈鱼可以有一个长期持久的影响，在富营养化湖泊的鱼类群落，特别是如果猎物鱼丰富，结构复杂的湖泊是低的。此外，0+鲈鱼的早期食鱼可能有助于防止预期的增加0+鲤减少成年鲤，这被认为是重要的，以确保生物操纵实验的长期成功。
1. We studied the population dynamics of 0+ fish in a eutrophic gravel pit lake in which predation of 0+ Eurasian perch on other 0+ fish was suspected to influence perch growth and the structure of the fish community, with effects on the lake food web. 2. The adult fish community was dominated by piscivorous species, especially perch, and the 0+ fish community was dominated by perch and bream. Bream grew to a total length of 80 mm between May and the end of August, gradually decreased in numbers during the summer, and completely disappeared in autumn. Stomach analysis revealed that 0+ perch ≥28 mm fed on 0+ bream. 3. The initially unimodal cohort of 0+ perch gradually broadened and became bimodal by the end of July. Fish of the larger, piscivorous cohort grew faster (1.4 mm day -1 ) than the smaller, zooplankton-consuming fish (0.6 mm day -1 ). Although individuals of both cohorts later consumed zooplankton and grew at similar rates (0.5 mm day -1 ), only perch of the large cohort (mean TL 125 mm) were found by mid-October. Intraspecific competition for food or cannibalism of older perch may have contributed to the disappearance of the smaller perch. 4. Early piscivory of the fast-growing 0+ perch apparently resulted in the disappearance of 0+ bream by the end of the growing season and precocious maturation of male perch. In contrast to findings in other studies, these large 0+ perch thus avoided the juvenile bottleneck by switching to piscivory early during their ontogenetic development. 5. The observations of this study suggest that early piscivory of 0+ perch can have a long-lasting impact on fish communities in eutrophic lakes, particularly if prey fish are abundant and the structural complexity of the lake is low. Furthermore, early piscivory of 0+ perch may help prevent the expected increase in 0+ cyprinids following reduction of adult cyprinids, which is considered important to ensure the long-term success of biomanipulation experiments.