A new method for studying spiders using vibrations

Abstract

Spiders play an important ecological role as omnivorous predators, being an important food source for many other species and a bioindicator of environmental health. However, spiders have not been well studied. Given their importance, spider survey methods used to determine differences in spider diversity and abundance should be compared to understand their limitations and biases. A new survey method attracting spiders based on the vibrations of an idling diesel tractor was tested and compared with traditional methods of pitfall traps and manual collection of spiders at night. A total of 2,294 spiders representing 34 families, 138 genera, and 226 species were identified across the three survey methods. Spider species diversity and abundance in spiders collected at night were significantly higher than in the other two methods (spiders collected with pitfall traps and attracted to vibrations). Spider collection using night collection and the vibration-based method was very similar in terms of labor required and material costs. Of the spider species identified, 80% were captured by hand, 30% by pitfall trapping, and 30% by vibration trapping. Although most spider species captured by pitfall trapping are known to be primarily terrestrial, both arboreal and terrestrial spiders were captured at night, when attracted and trapped using the vibration method.