Clutch Size Related to Hunting Manner of Spider Species

Abstract

Clutch size among species of spiders is positively correlated with length of adult female of the species; regression equations are provided, calculated from published data. Additional factors, manner of hunting (type of web or degree of hunting activity) and habitat, appear systematically related to clutch size. Available information on number of clutches suggests overall natality is closely related to clutch size in spiders. More-sedentary web spiders and the less-active non-web spiders, in the series Clubionidae, Gnaphosidae, Salticidae, Lycosidae, Thomisidae, have higher egg production. However, web spiders (Pholcidae, Agelenidae, some Theridiidae) which live in habitats of supposedly low prey encounter rates have both low egg production and more care of offspring than other web spiders.