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Psyche 
[Vol. 93 
Figure 2. Diagram of the frame used in this study, showing a spider monitoring 
its web from the front, moss-covered sector. 
Frames and suspension lines were cleaned of all visible silk 
strands before spiders were released at 16:00 onto the top center of 
each frame. Frames were checked the following morning at 8:00 and 
the presence of webs and position of spiders recorded. A capture 
web was defined as a web with sticky (cribellar) prey capture silk. In 
contrast with the non-sticky, single-line resting web, the capture web 
usually consisted of multiple, diverging threads. Spiders always 
hung near one of the web’s attachment points (Fig. 1) and it was 
noted whether this was a moss-covered or bare site. During the first 
three days and last day of the study only a single specimen was re- 
leased onto each frame. On other days, one large and one small 
specimen were released on each frame. This was done to compensate 
