>My co-worker is having a problem with bees and wasps in his bird nest
>boxes. This is the first time he has had such an overwhelming problem.
>What, if anything, can be done? Our pollinator population has enough
>trouble as it is, I would hate to" rob Peter to pay Paul" on this one.

Put in lots more boxes and keep everyone happy?

Cleaning out nest boxes thoroughly before spring might help. Bumblebees
prefer nesting materials to be already available, so do their best to find
old rodent (and bird) nests rather than starting from scratch. You can put
in boxes especially for bumblebee, too, though it's probably too late for
this year. There are several bumblebee books, Bumblebee Economics by
Heinrich, which I've just started reading, and Humblebee Bumblebee by
Griffin, which I haven't got hold of yet, but I'm told is good. Both
contain plans for making nest boxes. I've also heard of another simple
scheme that I haven't tried yet: take an old kettle, punch some holes in
the bottom for drainage, put in a handful of dried grass, dog fur, or
similar nesting material, and some used rodent bedding if possible as an
attractant. Bury it with the spout sticking out, preferably protected from
rain. In principle you can leave to top above groun too, and open the lid
to peak from time to time, but doing that could cause enough disturbance to
prevent the nest from thriving.

Wasps, well, if it's german yellow jackets, kill 'em with no regrets.
They're an invasive species and do no good. They've pretty much wiped out
our less aggressive native yellow jackets around urban/suburban areas. The
method recommended by some wasp people I know is to use about 1/4 tsp of
Sevin powder in the entry way, after dark. For some reason the y.j.s are
less likely to interpret this as an attack than other methods, but wear
protective clothing anyway, and don't carry a light. After they're all
dead, clean the box thoroughly to get rid of remaining traces of sevin. If
brave, and if the box is easy to close up and detach, it might also be
possible to trap them all in there after dark and dunk the whole thing in
soapy water. But be careful--y.j.s generally manage to have back doors,
and can get through pretty small cracks.

If unsure of ID, catch one with a bug net, pop it into a vial of rubbing
alcohol, and send it to Cooperative Extension.

>Is it related to the wet season?

Dunno, though maybe if the soil was soggy at the wrong time they'd be more
inclined than usual to go for above ground homes.


--
Allyn Weaks allyn at teleport.com
Seattle, USDA zone 7-8
Pacific Northwest Native Wildlife Gardening:
http://www.teleport.com/~allyn/natives/