Tso IM, Severinghaus Ll
Institute of Zoology, Academia Sinica, Taiwan
Anim Behav. 1998 Jul;56(1):219-25. doi: 10.1006/anbe.1998.0770.
In this study we used field surveys and experiments to investigate silk stealing, a unique form of kleptoparasitism. We studied the role that silk stealing plays in the interactions between a kleptoparasitic spider Argyrodes lanyuensis and its giant wood spider host Nephila maculata by testing: (1) if silk stealing generates any cost to the hosts; (2) if the amount of web lost to kleptoparasites varies with the size of the host; and (3) how prey stealing by A. lanyuensis affects N. maculata. Compared with uninvaded webs, N. maculata webs invaded by A. lanyuensis suffered an average orb reduction of 21%. There was a significant negative correlation between the percentage web reduction and body length of N. maculata, indicating that the impact of silk stealing was greater on younger hosts. No significant correlation was found between the number of A. lanyuensis on orbs and orb loss, but there was a significant negative relationship between percentage orb loss and silk diameter of N. maculata. These results suggest that the finer silk of smaller hosts may be at least partially responsible for their higher percentage orb loss. While prey stealing by other Argyrodes species greatly affects the foraging gain of hosts, A. lanyuensis did not seem to affect N. maculata. This was because the host took larger prey than the kleptoparasite did, and less than 3% of the host's biomass intake came from prey that A. lanyuensis would steal. Copyright 1998 The Association for the Study of Animal Behaviour.
在本研究中，我们通过实地调查和实验来探究偷丝行为，这是一种独特的盗寄生形式。我们研究了偷丝行为在盗寄生蜘蛛兰屿银斑蛛与其巨型木蜘蛛宿主斑络新妇之间的相互作用中所起的作用，具体测试了：（1）偷丝行为是否会给宿主带来任何代价；（2）被盗寄生者偷走的蛛网数量是否会随宿主大小而变化；（3）兰屿银斑蛛偷食猎物对斑络新妇有何影响。与未被入侵的蛛网相比，被兰屿银斑蛛入侵的斑络新妇蛛网的平均圆网面积减少了21%。蛛网减少的百分比与斑络新妇的体长之间存在显著的负相关，这表明偷丝行为对较年轻的宿主影响更大。未发现兰屿银斑蛛在圆网上的数量与圆网损失之间存在显著相关性，但圆网损失百分比与斑络新妇的蛛丝直径之间存在显著的负相关关系。这些结果表明，较小宿主的较细蛛丝可能至少部分导致了它们较高的圆网损失百分比。虽然其他银斑蛛物种偷食猎物会极大地影响宿主的觅食收益，但兰屿银斑蛛似乎并未对斑络新妇产生影响。这是因为宿主捕获的猎物比盗寄生者捕获的更大，而且宿主生物量摄入中来自兰屿银斑蛛会偷走的猎物的比例不到3%。版权所有1998动物行为研究协会。
