Zimmermann Manfred, Spence John R
Department of Entomology, University of Alberta, T6G 2E3, Edmonton, Alta., Canada.
Oecologia. 1989 Aug;80(2):187-194. doi: 10.1007/BF00380149.
Prey of feeding juvenile and adult Dolomedes triton (Walckenaer 1837) were sampled over two seasons on three small ponds in central Alberta, Canada. Prey were mainly insects active at the water surface with truly aquatic species making up about 14% of the diet. Throughout the season aquatic and semi-aquatic Heteroptera represented about 30% of the prey. Diptera and adult Odonata were also important prey items but their abundance in the diet was more variable seasonally. Of the 625 prey items recorded nearly 50% were represented by taxa taken no more than once by spiders in one of the five size classes (adult females, adult males, large, intermediate and small juveniles). Large spiders did not take the smallest prey available, although small and intermediate-sized spiders fed on nearly the full size range taken by larger spiders. Cannibalism was common, accounting for 5% of the observations, with females and large juveniles as the most frequently observed cannibals. We hypothesize that intraguild predation (including cannibalism) could be an important coevolutionary force structuring phenology, population dynamics and microhabitat use of the predatory guild of the neuston community.
在加拿大艾伯塔省中部的三个小池塘中，对处于捕食阶段的幼年和成年横纹盗蛛（Dolomedes triton，Walckenaer 1837）的猎物进行了两个季节的采样。猎物主要是在水面活动的昆虫，真正的水生种类约占其食物组成的14%。在整个季节中，水生和半水生异翅目昆虫约占猎物的30%。双翅目昆虫和成年蜻蜓也是重要的猎物，但它们在食物中的丰度随季节变化更大。在记录的625个猎物中，近50%是由五个体型类别（成年雌性、成年雄性、大型、中型和小型幼蛛）中的蜘蛛捕食不超过一次的分类单元所代表。大型蜘蛛不会捕食最小的可用猎物，尽管小型和中型蜘蛛捕食的猎物大小范围几乎与大型蜘蛛相同。同类相食很常见，占观察结果的5%，其中雌性和大型幼蛛是最常观察到的同类相食者。我们推测，集团内捕食（包括同类相食）可能是塑造漂浮生物群落捕食者集团物候、种群动态和微生境利用的重要协同进化力量。
