BEHAVIOR OF COLONIAL ORB-WEAVING SPIDERS DURING A SOLAR ECLIPSE

The behavior of colonial orb-weaving spiders (Metepeira incrassata) in tropical Veracruz, Mexico was studied during the total solar eclipse on July 11, 1991. Spiders behaved in a manner typical of daily activit y until totality, when many began taking down webs. After solar reappe arance, most spiders that had begun taking down webs rebuilt them. The re was no significant difference in the overall activity patterns of s piders during totality across a range of colony sizes. Experimental il lumination of part of a colony during totality altered web takedown be havior. While spiders in the darkness of totality began to take down w ebs, those spiders which were artificially illuminated did not. These observations suggest that the primary environmental cue responsible fo r the daily rhythm of web building behavior in this species is light l evel.