Because yellowjackets do not produce or store honey one might wonder why striped skunks, raccoons and black bears frequently dig up their underground nests. It is the young yellowjackets (larvae), not honey, that is so highly prized by these insect-eating predators. At this time of year it is crucial for them, especially black bears who go for months without eating or drinking during hibernation, to consume enough protein to survive the winter.
Whereas adult yellowjackets consume sugary sources of food such as fruit and nectar, larvae feed on insects, meat and fish masticated by the adult workers that feed them. This makes the larvae a highly desirable, protein-rich source of food. (Yellowjacket larvae reciprocate the favor of being fed by secreting a sugary material that the adults eat.)
Three to five thousand adult yellowjackets can inhabit a nest, along with ten to fifteen thousand larvae. Predators take advantage of this by raiding the nests before frost kills both the adults (except for fertilized young queens) and larvae in the fall. Yellowjackets are most active during the day and return to their underground nest at night. Thus, animals that raid them at night, such as raccoons, striped skunks and black bears, are usually very successful in obtaining a large meal. Occasionally, as in this photo, the yellowjackets manage to drive off predators with their stings, leaving their nest intact, but more often than not the nest is destroyed and the inhabitants eaten. (Thanks to Jody Crosby for photo op of yellowjacket nest (circled in red) dug up by a black bear – note size of rock unearthed.)
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