Prey capture and feeding efficiency of social and solitary spiders: A comparison
Acta Zoologica Fennica
1990
Journal Article
190
339-343
Reserva Nacional Tambopata animals invertebrates arthropods Arachnida spiders Anelosimus eximius predation animal behavior ecology Madre de Dios Bibliography
Prey capture was monitored in two spider species. A social species, Anelosimus eximius, was studied in a subtropical forest of SE Peru. A solitary species, Achaearanea tepidariorum, was studied in an urban habitat of SW Ohio, USA. The size distribution of prey captured and efficiency with which each of the spider species captured prey in various size classes were determined from field observations. The ability of each of the species to utilize the resources contained in prey in several size classes was determined by a measure of weight loss of the prey during feeding. An. eximius captured a greater range of prey sizes with approximately the same efficiency. This social spider removed a high percentage of the prey biomass in all size classes. The size range captured by the solitary Ach. tepidariorum was not as great as it was for the social spider and the capture efficiency of this species declined with prey size. In laboratory experiments, the solitary spider removed a very high percentage of the edible biomass of small prey but was much less successful at completely consuming large prey. These data suggest that the capture of large prey is a characteristic of spiders that forage in groups, whereas the solitary species is specialized to feed effectively on small prey.