Subterranean Spiders

A neat paper has just appeared in the Journal of Arachnology (2011, Vol 39: 393-398), titled “Vertical distribution of spiders in soil” by Laska et al.   (you can visit the Journal by clicking here).  The authors studied spiders in soil by using a modified subterranean trap that collected animals up to depths of 95 cm.  They studied in six different sites in the Czech Republic, and in all but one of the sites, they collected spiders at depths greater than 90 cm.    Although I was not surprised that Linyphiids were among the deepest-dwellers, they also found at Nesticidae  and Dysderidae inhabiting the deep.  Although some of the sample sizes were small, their habitat coverage was broad, and the evidence of soil-dwelling spiders is strong – and they also suggest that in some habitats, the spiders likely had to arrive there by means other than vertical movement – this means there is a vast and fascinating “subterranean environment created by a system of voids”.  This is pretty interesting and has caused me to rethink my own long-held assumption that spiders seldom move into the soil, and instead largely occupy the organic matter above soil.   I may just have to tackle this kind of project in my local forests and see if similar results are found this side of the big pond!