Likening it to providing more runways at busy airports, researchers at North Carolina State University found in a new study that adding protruding rocks to restored streams can help attract female aquatic insects that lay their eggs on the rock bottoms or sides.
More eggs that hatch into larval insects is great news for stream restoration because the re-establishment of organisms, such as insects, is often slower than expected in restored streams, says Brad Taylor, associate professor of applied ecology at NC State and corresponding author of a paper describing the research. A thriving population of stream insects generally portends good water quality, overall stream health, and provides food for fish, amphibians, reptiles, and even birds, he adds.
Most stream insects use rocks protruding above the water as runways to land on, then crawl underwater and attach their eggs to the underside of the rocks. Because restored streams sometimes fail to regain their abundance of aquatic insects even decades following restoration, researchers were interested in testing whether increasing egg-laying habitat the rock landing areas would increase the abundance and diversity of insect eggs and larvae.
Read more at North Carolina State University
Image: A caddisfly egg mass sits on the underside of a protruding rock. (Photo courtesy of Brad Taylor, NC State University)