Subject: Cuckoo Migration
Date: Dec 14 19:38:11 1997
From: B&P Bell - bellasoc at mail.isomedia.com


Hi Tweets -

Some comments on the Cuckoo thread -

Gene Hunn is correct, in northern California the general time of cuckoo
arrival is late June to early July.

During one study of potential cuckoo nesting at the Bobelaine Audubon
Sanctuary on the Feather River a pre study training session was held by
Steve Laymon. The information given was that YBCs in the Sacramento
Valley were found in relatively undisturbed riparian forest in close
proximity to orchards, often walnut orchards. Presumably because of a
good supply of "worms" for food. The best information on nesting sites
was to look for large old willow trees with overhanging branches
providing good access to a nest site, but also good cover. During our
study in the late 80s, we found a number of YBCs, on one occasion having
9 observations of a minimum of 6 separate cuckoos. They almost uniformly
occured sitting fairly high in a tree, but with a good overhead cover
(the one exception was the bird seen on our arriving and walking up the
levee - it flew overhead from the adjoining walnut orchard with a large
larva of some sort and disappeared into the forest). Most of those were
in relatively close proximity to a series of bar (borrow) ponds along
the western side of the sanctuary. These ponds act as the overflow
chutes for the Feather River during high flood conditions. Alas, we
never located a nest, but continued to have reports of cuckoos until
they left apparently sometime in August. The lack of nest location might
have had somewhat to do with the very dense undergrowth, much of it made
up of some of the most luxurient growth of poison oak you have ever
seen, present throughout much of the sanctuary.

Bobelaine is owned by National Audubon, and managed by Sacramento
Audubon. It is 430 acres, up to one-quarter mile wide and one-and-a-half
miles long, of relatively undisturbed riparian forest - or was until
1993 when a runaway fire ran about six miles down the Feather River
inside the levees. The fire basically destroyed the northern two-thirds
of the sanctuary (old growth Fremont Cottonwoods, Populus fremontii).
The fire was stopped just as it was getting into the magnificent old
oak/woodland portion of the sanctuary. The understory has made a good
recovery, and replanting has been ongoing. In spite of the fire the
sanctuary is worth a stop for anyone on a trip south through the
Sacramento Valley. Any time of year - one April the birdathon recorded
90 species within this 430 acres.

Happy Birding,

Brian H. Bell
Woodinville, Wa
bellasoc at isomedia.com