SEASONAL VARIATION IN EGG HATCHING AND 
CERTAIN EGG PARAMETERS OF THE 
GOLDEN SILK SPIDER 
NEPHILA CLAVIPES (ARANEIDAE)* 
By T. E. Christenson, P. A. Wenzl, and Peter Legum 
Department of Psychology, Tulane University 
New Orleans, LA 70118 
Introduction 
Little is known about seasonal variation in the reproductive suc¬ 
cess of spiders. Few field data, for example, are available on temper¬ 
ate egg productivity in relation to the phase of the season in which 
the female matured and in which the egg clutch was laid. Wise 
(1976) found that female filmy dome spiders ( Neriene ) who matured 
early in the summer laid more and lighter eggs than those who 
matured later. Levy (1970) noted that the early season crab spider 
(Thomisus) egg sacs contained more spiderlings than those laid 
toward the end of the season. Kessler (1973) noted that under field 
conditions the first egg sac of the wolf spider ( Pardosa ) contained 
more eggs than the second; it is probable that some of these late 
season clutches were the later ones produced by given females. 
The present study focuses on the seasonal variation of egg hatch¬ 
ing and certain egg parameters of a temperate population of the orb 
weaving Nephila clavipes. Mating occurs from July through Sep¬ 
tember, with a given female mating several times just after her final 
molt (Christenson and Goist, 1979). Females may copulate after this 
period, but usually when feeding. Productive females lay their eggs 
in one to three elaborate egg sacs from mid-August through early 
December (Moore, 1977; Christenson and Wenzl, manuscript sub¬ 
mitted). The female abandons the egg sac after its completion, 
directing no further attention toward it. Males die by late Sep¬ 
tember and females by mid-December. Second instar spiderlings 
overwinter in the sac for six to eight months, and emerge under 
favorable conditions in the spring. The eggs have been described 
(Moore, 1977), and the functions of the egg sac and major causes of 
egg and early spiderling mortality have been discussed (Christenson 
and Wenzl, manuscript submitted). 
* Manuscript received by the editor November 27, 1979 
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