Eadie John McAllister, Keast Allen
Department of Biology, Queen's University, K7L 3N6, Kingston, Ontario, Canada.
Oecologia. 1982 Nov;55(2):225-230. doi: 10.1007/BF00384491.
We tested Eriksson's (1979) hypothesis that goldeneye and perch compete for invertebrate prey. (1) Diet overlap was high on both prey type (71%) and prey size (80%). Ephemeroptera nymphs and Trichoptera larvae made up over 65% of the stomach contents of goldeneye and perch, and over 80% of the diets of both species were organisms in the 0-20 mm size range. (2) Goldeneye and perch co-occurred on all three study lakes but there was an inverse relationship between their abundances on nine study plots within those lakes. This reciprocal density trend was not due merely to differences in habitat use by perch and goldeneye. When variation in habitat structure was controlled via partial correlation techniques, the reciprocal density trend remained. (3) An alternative hypothesis that density dependent predation maintained habitat separation of perch and goldeneye was not supported. (4) Food resources were limited in at least some sites. (5) Sites which supported populations of both perch and goldeneye had a significantly greater diversity of resources and a tendency toward higher levels of food production than sites in which only one or neither species occurred. (6) We cannot reject Eriksson's (1979) hypothesis. Our results are in agreement with his studies in Sweden and suggest that interactions between goldeneye and Perca spp. may be comparable over large geographic areas.
我们检验了埃里克森（1979年）提出的鹊鸭和鲈鱼争夺无脊椎动物猎物的假说。（1）在猎物类型（71%）和猎物大小（80%）方面，饮食重叠度都很高。蜉蝣若虫和毛翅目幼虫占鹊鸭和鲈鱼胃内容物的65%以上，且两种物种80%以上的食物都是体长在0至20毫米范围内的生物。（2）在所有三个研究湖泊中，鹊鸭和鲈鱼都同时出现，但在这些湖泊内的9个研究样地中，它们的丰度呈负相关关系。这种相互的密度趋势并非仅仅是由于鲈鱼和鹊鸭栖息地利用的差异所致。当通过偏相关技术控制栖息地结构的变化时，这种相互的密度趋势仍然存在。（3）一种认为密度依赖捕食维持了鲈鱼和鹊鸭栖息地隔离的替代假说未得到支持。（4）至少在一些地点，食物资源是有限的。（5）同时支持鲈鱼和鹊鸭种群的地点，其资源多样性显著更高，且与仅有一种物种出现或两种物种都不出现的地点相比，有食物产量更高的趋势。（6）我们不能拒绝埃里克森（1979年）的假说。我们的结果与他在瑞典的研究结果一致，并表明在大地理区域内，鹊鸭和鲈属物种之间的相互作用可能具有可比性。
