Beetles, Pacific Northwest
Darkling Beetle are one of the most common members of the beetle community. Mostly, they are dark colored and spend a good deal of time walking about on the ground.
These beetles feed on dead plants but also will eat fresh plant material. They prefer walking to flying. Their tracks easily can be observed in sandy areas. Darkling beetles are active both at night and during the day.
Many of these beetles have a very interesting defense mechanism. If disturbed, they assume a head down and tail up position, and if handled roughly, they emit a dark colored and foul smelling fluid. This behavior is enough to discourage all but the most determined predators. The fluid washes off easily with water in case of contact with your hands.
Most species of Darkling Beetles are active above ground through spring, summer and fall. With the onset of winter weather, some species seek shelter below ground in burrows of other animals and remain there until warmer weather returns in the spring.
Other species of darkling beetles do not live through the winter as adults. They lay eggs in the soil during warm weather and die with the onset of freezing. Their eggs hatch into larvae when warm weather returns.
These larvae live in the soil for up to two years before the adults emerge to eat and reproduce.