Subject: Re: Hutton's Vireos
Date: Jan 13 01:33:48 1998
From: jbowling at direct.ca - jbowling at direct.ca


** Reply to note from Kyle Elliot

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Earlier, Michael Price suggested that Hutton's Vireos might be migratory
in the Pacific Northwest. I have not noticed this with the local pairs
(2-3) which nest/winter in Cougar Canyon (Delta BC, just south of
Vancouver.) The habitat is mostly deciduous, with some old-growth. Both
nests I have found have been in young (30 feet maximum tall) cedars. I
follow them quite religiously, and have their daily patterns quite mapped
out, so I am pretty certain it is the same pairs during both summer and
winter. I would suggest, then, that most pairs are not migratory.

However, I have heard of people banding them in fairly large
numbers in Washington State during migration. I also saw one at Iona
in 1995; I doubt it was resident. So, I guess some do move. Perhaps it
depends on age; young birds seem to disperse from Cougar Canyon in fall.

Although I have not noticed any regional "dialect" in their songs, I have
observed them calling on several occasions. They have a very rasping,
harsh call; quite different from the Ruby-crowneds "chi-di-dit". I find it
useful in confirming identification (although it is pretty rare to hear
them call).

I am also interested in the seeming increase in Hutton's Vireo sightings.
Is this just increased observer awareness, or a real increase. I would
have thought them to be decreasing due to Brown-headed Cowbird parasitism.
Jamie Smith tells me that they are are one of the species hardest hit in
his study in Burns Bog. Neither of the nests I found in the canyon had
BHCO evidence. An example of the increase is the Reifel/Alaksen (an area
notorious for BHCO density). There were at least two nesting pairs last
year.

Are Hutton's Vireos decreasing/increasing elsewhere in Tweeterland?
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Glad to see you on Teeters, Kyle. I appreciated your efforts on the "Vancouver
Birds in 1995" project. As in most things birdy, we have a lot to learn about
this one. I include below a paste from the summer 1997 "Field Notes" summary
which describes an interesting bit on Hutton's Vireo:

"A late report from the spring (of 1997), a male *Hutton's Vireo* was heard
singing at Windy Bay, S. Moresby I., Q.C.I., May 27 (AD), the first vireo of
any kind reported from the archipelago."

Adrian Dorst is well-acquainted with this species from his Tofino home. Obviously,
there is some vagrancy - albeit short-distance - in this instance.

Also, here is another bit from the winter 1995-96 "Field Notes":

" S.A. The status of Hutton's Vireos in the Sunshine Coast is typical of the rest
of its s.w. B.C. range. The species is normally recorded as scattered singles
during the non-breeding season, becoming conspicuous only as the males start to
sing in January-February. This winter they began singing in early February, after
which they were commonly heard in second-growth Douglas Fir stands throughout the
area, e.g. four at the Sechelt Airport Feb. 16 (TG). Indeed, the Sunshine Coast
may be the centre of abundance of Hutton's Vireos in the Region. What is unknown
is if these are all resident birds, or if some migration from the south is
involved."

Tony Greenfield told me that they were more common during this period than at
any other time in his 20+ years in the Sechelt area. His feeling is that some
migration must have been involved. Either that or some years, Hutton's Vireos
just *want* to sing more often and be heard! My gut feeling is that there has
been a population increase in Hutton's Vireos in the PNW over the past several
years, and its distribution is expanding commensurately.

- Jack









Jack Bowling
Prince George, BC
jbowling at direct.ca