Do adult mosquitoes support terrestrial predatory invertebrates? A study of emergent mosquitoes from tires piles and the surrounding spider communities

Although the historical focus of research on isolated container systems (tires, tree holes) has been on the role of terrestrial resource subsidies (leaves) in supporting aquatic insect communities, little is known of the reciprocal contribution of emergent aquatic insects to surrounding predator communities. We predicted that if emergent adult mosquitoes from containers are an important resource for spiders, then there would be differences in abundance, richness, and composition of spiders around tire piles with emergent mosquitoes compared to piles lacking adults. Likewise, we predicted that as the distance from an established tire pile increases, spider communities would change do to decreasing inputs of prey. We established nine tire piles consisting of ten tires each which were separated into three treatment levels: all tires with water and emergent adults, half with water and emergent adults, and all tires without water. Prior to and six and twelve weeks after establishment spiders were collected along four transects at four distances from each tire pile and from each tire. In general, tire piles with water in all tires had significantly more spiders than did piles half filled with water, with piles half filled with water having more than piles with no water: abundance did not vary with distance. We also evaluated differences in richness and composition among treatment levels. Our work is the first to consider the effect of emergent adults from aquatic containers on spiders, and is one of the few studies to quantify the specific contribution of mosquito adults to supporting spiders.