Distribution and Abundance of Adult Aquatic Insects in the Forest Adjacent to a Northern California Stream

Publisher Website
Google Scholar
Abstract
The distribution of adult aquatic insects in the mixed evergreen forest adjacent to Big Sulphur Creek, Sonoma Co., Calif., was examined using sticky traps (0.26 m2 each) that were placed in trees at three distances (5, 40, 150 m) from the stream and at three heights (2, 5, 8 m) above the ground. Species richness, number of individuals, and biomass of aquatic insects, and number of individuals for seven of 12 common aquatic insect taxa decreased (P ≤ 5 0.05) as distance from the stream increased. Species richness, number of individuals, and biomass of aquatic insects showed no relationship with height above the ground, but of the 12 common taxa, three were most abundant near tree tops and one was most abundant near tree bases (P ≤ 0.05). Adult aquatic insects represented 36.9 and 15.4% of total arthropod numbers and 25.3 and 10.7% of total arthropod biomass at the 5-m and 150-m sites, respectively. The abundance of adult aquatic insects in the forest bordering this stream suggests that adult aquatic insects provide an important conduit for energy and nutrients from the aquatic system to the terrestrial food web.