[EBB Sightings] Swainson's Hawks (continuing)

Folks:

I stopped by Lindemann (Alameda Co.) and Herdlyn (Contra Costa Co.) road 
during the heat of the day on Thursday, 6/30/2005.  A field off Lindemann 
apparently is still full of voles as I counted 57 SWAINSON'S HAWKS on the 
ground and perhaps another 10 were in the air.  Also working the field were 
one or two Red-tailed Hawks and 10-20 American Crows and 10-20 Common 
Ravens.  I watched the Swainson's and the two corvids consuming 
voles.  Some Swainson's were also soaring with voles in their 
talons.  Perhaps they were going elsewhere or were just showing what good 
providers they could be.

Off Herdlyn, I found only two Swainson's Hawks.

There are some interesting papers on population explosions and crashes in 
Meadow Voles in central California.  Surprising to me is that these are not 
locked into our seasons, but seem to just happen.  The Swainson's appear to 
have figured this out a long time ago, which is why they are still around, 
I suppose.  This is quite a show--thanks to all who have continued to post 
to this list about this interesting concentration.

Bill Bousman
Menlo Park