Apidae

I went to Coyote Hills preserve with the family today, and caught a large bumble bee - however, since I already have a bumble bee specimen, and bumble bees are becoming threatened species, I decided to let him go. Before I released him, I took a few nice photographs and was able to identify him based on these photographs.

Hymenoptera; Aculeata; Apoidea; Apidae; Apinae; Bombini; Bombus vosnesenskii
Common Name: Yellow-faced Bumble Bee

This specimen is approximately 1.5 inches long, with two yellow stripes and a yellow face. Not much is known about bumble bees. They form colonies with usually 50 members, not as organized or specialized as honey bee or ant colonies. Because the founder female has to make or choose a burrow, it is not very large or she settles in a vacant burrow made by a ground animal. The area in which this specimen was caught was covered with ground squirrel burrows, so it is likely that one of those burrows contains the nest. In the first picture above, the bee is cleaning its face (cute, I think). Their populations are threatened by habitat destruction, diseases from commercially raised bumble bee populations, and invasive social insects such as the Pennsylvania Yellow Jacket, which is able to forage more nectar and compete for space.

I also snapped a photograph of this fly, which looks like a Tachinid fly, but could easily be a different family, as many similar looking flies are members of different families.