Early-Season Activity and Habitat Characteristics of Terricolous Spider Families (Araneae) in an Appalachian Oak-Mixed Hardwood Forest

Abstract

Spiders of 24 families were collected by pitfall traps in an oak-mixed hardwood forest in northcentral West Virginia during an 11-wk period in early summer of 1989-1992. All trapped individuals were identified at least to the family level. Quantitative vegetation data allowed assessment of spider habitat associations on a finer spatial scale than previously reported. The Lycosidae dominated each year despite great annual variation in abundance for each family. Percentage of fern coverage on a plot basis was related inversely to abundance of Thomisidae and Gnaphosidae, but related positively to abundance of Linyphiidae, a reflection of the strategies of the families. There was a strong positive correspondence between abundance of the Thomisidae and percentage of oak basal area in the overstory. Pitfall-trap catches were biased slightly toward capture of male spiders; average sex ratio (male:female) for hunting-spider families over the 4 yrs was 8.1:1, and for web-spinners was 2.5:1. Abundance of juvenile spiders (over all families) varied temporally and was related inversely to total abundance.