Animal community ecology has traditionally focused on energy
and nutrients as the main ecological currencies influencing species
interactions. However, water is a resource with an extremely important
physiological role and dehydration can have important impacts on growth,
activity, reproduction, and survival. As such, this resource may often be the
most limiting in many environments or at certain times in most environments.
Here we present preliminary evidence of water-mediated interactions between
crickets and wolf spiders from several experiments. In one laboratory study, large
adult wolf spiders (Hogna carolinensis) were acclimated
to cages and given food and water ad libitum. Water
was then removed from cages and consumption of juvenile house crickets (Acheta domesticus) was examined
daily. These spiders consumed more crickets than spiders that had continual
access to water. From another laboratory study, we present evidence of a
threshold resource ratio for consumption of house crickets by wolf spiders, based
on the water:dry-biomass
ratio of the crickets. This suggests a trade-off between the water content of
prey and water loss associated with predation. Together, these experiments
suggest that rates of consumption by spiders are determined in part by the
water content of their prey and thus interaction strengths between these predators
and common prey items are influenced by water.