An online resource based on the award-winning nature guide – maryholland505@gmail.com

Archive for July 3, 2013

Adult Stoneflies Emerging

7-2-13 stonefly adult 058Stoneflies spend their larval stage on the bottom of streams, in amongst the stones for which they’re named. Some species of larval stoneflies feed on decomposing organic matter, others are predators. As adults, very few stonefly species feed due to their short life span. Those that do feed on algae and lichens, nectar, or pollen. After shedding their skin 10 to 22 times (depending on the species), the larvae crawl out of the water, split their skin a final time and emerge as winged adults. Most emerge in the spring or early summer, though some species mature in the fall, and even in winter. Most larvae spend 10 to 11 months under water, and only 1 to 4 weeks as terrestrial adults. The adults spend their days hiding on the branches or leaves of streamside vegetation, and crawl around at night. They usually only fly to disperse to a new habitat, which is surprising, given the size of their wings.