Subject: Cuckoo Migration (was: Weird Urban Peregrine Prey) (long)
Date: Dec 14 00:34:33 1997
From: Michael Price - mprice at mindlink.bc.ca


Hi Tweets,

Kelly Cassidy writes:

>The cuckoo in question was reportedly photographed in June, which seems a
>tad late to be migrating (but with all due consideration to Michael
>Price's frequent reminders that "late" is relative; I have no idea when
>YBCs migrate).

Kelly, just happened to be looking for Allosaur teeth in the earliest
Cretaceous strata of my desk, and came upon, mirabile visu, a copy of the
Long Point (Ontario) Bird Observatory Checklist for 1985 someone gave me
when the world was green, a lovely *bar-graph* checklist for a location that
has among the best migrational datasets in N Amer.

Black- & Yellow-billed Cuckoo Seasonal Distribution at Long Point, Ontario:
* Single; + Rare; x Uncommon; xxx Common

Black-billed Cuckoo
xxxx xx
xxxx xx
+xxxxxxxxxxxxxxxxxxxxxxx ++ *
----|----|----|----|----|----|----|----|----|----|----|----
J F M A M J J A S O N D


Yellow-billed Cuckoo
xxxxx xxxxx
xxxxx xxxxx
++xxxxxxxxxxxxxxxxxxxx++++ *
----|----|----|----|----|----|----|----|----|----|----|----
J F M A M J J A S O N D


For BC:
BC Records of Yellow-billed Cuckoo as in Campbell et al's Birds of BC:
x - one record

May Jun Jul Aug

No date 1 3 2
Week 1 2 2 2
Week 2 2 1 1
Week 3 1
Week 4 3 1 1
_____ _____ _____ _____

4 9 5 4



Of known dates:
x x
week x xx x x
1234 x xxxx x x xx
----|----|----|----|----|----|----|----|----|----|----|----
J F M A M J J A S O N D



Total BC records: x
x
YB Cuckoo x BB Cuckoo x
x x
x x
x x x x
x x x x
x x x x x x
x x x x x x x
x x x x x x x
x x x x x x x
-|-|-|-|-|-|-|-|-|-|-|- -|-|-|-|-|-|-|-|-|-|-|-
J F M A M J J A S O N D J F M A M J J A S O N D

The June peak is consistent with YB Cuckoo's northbound migration period.

There's actually a personal record of Yellow-billed Cuckoo, a calling bird
June 23 1973 at the W end of Lost Lagoon in Stanley Park at a time when I'd
just moved to Vancouver BC from Back East. I almost never saw any of the
local birders, and hadn't the faintest idea what as common or rare here. A
while later I did run into one of the local authorities who told me *most*
definitely that what I had been hearing was a territorial Pied-billed Grebe
(there was a pair nesting at the end at that time, apparently). Uh-huh,
say's I, won't the folks at the Ontario Nature Federation be interested when
I write to tell them that there's a race of Pied-billed Grebe in Vancouver
BC that's so behaviorally divergent that it nests forty feet up in a
broadleaf maple. I heard no more fool nonsense about grebes from that point.
One of life's little moments to savor.

>But, heavens, to where would it be migrating? The
>Seattle-Vancouver area is a ways north of remaining known breeding
>populations west of the Rockies. (Occassional breeders in eastern Oregon,
>maybe still breeding along the Columbia west of the Cascades?)

Well, Kelly, only the threat of facing a firing squad at dawn would force to
me to guess, but I'd say those early YB sightings are bona fide migrants,
but later YB June sightings might be either (displaced?) non-breeders or
maybe prospecting birds searching for tent caterpillar infestations.
Certainly BB's big July record spike suggests something beyond
honey-is-the-map-in-the-glove-compartment? lousy direction, and July is the
big hairy caterpillar month--Back East, anyway. I'm never entirely happy
with the term 'overshoot': something that many species do so consistently in
regular pattern in consistent numbers needs a term that's more descriptively
accurate of what it is that actually impels that species to regularly go
beyond its 'usual' boundaries.

>Personally, I prefer to believe in some hidden cuckoo enclave in
>Washington known only to 'grines.

Cuckoo Nuggets? Naaahhhh....

>So you attach a miniature camcorder and
>GPS unit to Stewart, plus a little jet pack to give him boost with all
>that hardware....

And an uplink to Atlantis. Seriously, would a satellite link be feasible
without needing to win the Big One?

>Or, perhaps a more feasible plan would be a video camera aimed at the Beacon
>Rock peregrine nest, where cuckoos seem more likely to turn up as prey.

Where old cuckoos go to die... '-)

Michael Price We aren't flying...we're falling with style!
Vancouver BC Canada -Buzz Lightyear, Toy Story
mprice at mindlink.net