Morse Douglass H
Department of Zoology, University of Maryland, 20742, College Park, Maryland, USA.
Oecologia. 1979 Jan;39(3):309-319. doi: 10.1007/BF00345442.
Crab spiders Misumena calycina (L.) in pasture rose Rosa carolina flowers regularly attacked bumble bees, smaller bees, and syrphid flies that visited these flowers. Attacks reached a maximum rate of over 20/h during mid morning, but only 1.6% of the most important prey item, bumble bees, were captured. The next most important food source, the most frequently taken item, syrphid flies Toxomerus marginatus (Say), were captured in 39% of the attempts. Since these flies have a biomass only 1/60th that of bumble bees, they comprised a much less important food source than did bumble bees. Spiders would obtain over 7% more food by specializing on bumble bees than by attacking all insect visitors, and as much as 20% more food at certain times of the day. However, they did not show a tendency to specialize at any time.
在卡罗来纳蔷薇花上的蟹蛛（Misumena calycina (L.)）经常攻击前来访问这些花朵的大黄蜂、小型蜜蜂和食蚜蝇。上午中旬攻击率最高超过每小时20次，但最重要的猎物大黄蜂只有1.6%被捕获。下一个最重要的食物来源，也是最常被捕食的对象，边缘食蚜蝇（Toxomerus marginatus (Say)），在39%的捕食尝试中被捕获。由于这些苍蝇的生物量只有大黄蜂的1/60，它们作为食物来源的重要性远低于大黄蜂。蜘蛛专门捕食大黄蜂比攻击所有来访昆虫可多获取7%以上的食物，在一天中的某些时候甚至可多获取20%的食物。然而，它们在任何时候都没有表现出专门捕食的倾向。
