:
> Could this be happening a lot right before our eyes and only noticed
> in the most extreme cases of disease or poisoning?

I also belive that it is happening all the time in hives.

Few practical observations to support this

I indoor winter few hundred hives every year. About +3 C completely
dark. Dead bees end up on floor, and they are not taken there by other
bees (who could not return). No bees flying ever unless I put on light.
Very few bees on bottom boards in spring only 10 – 40. On floor 0,3-0,5
litres/ hive. There is also trends in time when they come out depending
on last brood cycles. The time with heavies fall on floor can change by
1 -2 months depending on year and age cohorts of bees ( how old average
bees were in start of winter)  I believe the old bees walk out
voluntarily before dying in bottom.

In Finland we have very long flightless periods in winter, up to 6
months if early winter and late spring. If there is winter with warms
spells there is much less dead bees on bottom boards, and I never saw
bees taking dead ones out during winter. So they come out with their own
muscles. .

Last the more scientific observation. I have a friend who sent a lot of
time with scale hives. He had a system measuring 10 g differences every
5 minutes.   He saw in fall, especially after feeding and also after
long rainy periods days when hive lost 100 – 300 g of weight in less
than 30 min, and could not relate these losses to anything else than
bees leaving and not coming back. This happened normally in morning
after the weather had warmed for flying, and made same kind of curve in
data as bees going after nectar. But they were not coming back.

I would like to see data from bee counters about this. I remember a
study indicating that 5% of outgoing workers in a day do not return.

Ari Seppälä
Finland

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html