The Newsletter of Camp Denali
Early on the morning of July 8th, Housekeeping Supervisor, Elaina O’Brien, happened upon a truly rare spectacle among the staff cabins. Undulating across the pathway at her feet was a gray, snake-like apparition. On closer inspection, this was no snake, (which don’t occur in interior Alaska), but an assemblage of thousands (?) of insect larvae wriggling forward atop one another in a steadily-advancing, rope-like column roughly a meter long!
Fortunately, we knew just who to call. Derek Sikes (SES leader in 2015) is the curator of insects at the University of Alaska Museum of the North and a professor of entomology at the University of Alaska Fairbanks. We soon learned that these larvae belonged to a relatively common group of insects called dusky winged fungus gnats in the genus Sciara. Adults – tiny mosquito-like flies – are easily overlooked. The slightly larger larvae are a common garden pest. Soil-dwellers, they feed on decaying organic matter and fungal mycelium, and can deplete nutrients essential for plant growth.
Derek was thrilled to receive Elaina’s report. This particular fungus gnat was likely a new species, one that Derek and a post-doctoral student were literally in the process of describing for scientific publication. According to Derek, there have been a mere handful of sightings in Alaska (all recent) of the behavior that Elaina witnessed.
Why the larvae travel en masse and why they take on a snake-like shape are mysteries. In this instance, the dry, compacted path, and lack of leaf litter, may have caused them to gather into such formations, Derek theorized. Moving as one may also be a disguise: “it’s possible they are mimicking a snake because most birds (at least migratory birds) avoid snakes”, he explained. Indeed, as soon as the column of larvae began to vanish one-by-one into the leaf litter on the other side of the path, White-crowned Sparrows and Dark-eyed Juncos discovered and descended to feast on the remaining few.
