Hi Tweets

Linda Phillips writes:

>At this time of year I am more than anxious for Spring's arrival but my
meager records don't indicate that Spring is any earlier this year than
last.

Amen to that. We still have six to eight weeks of winter left: we're only
halfway through. What we're having is a warmer, wetter (*el Nino*?) winter
rather than an early spring, which I wouldn't expect until March at the
earliest. And it could become more severe/cooler/closer-to-average at a
day's notice of a seasonally-appropriate incursion of Siberian Express
cold-rain/snow mix or Continental Arctic High frigidity. Real spring is
actually still some considerable distance away.

Regarding singing (mostly male) birds in winter. Studies over many years
have shown that male courtship songs and breeding-territoriality are the
result of increased daily light duration incurring hormonal changes leading
to to these things. Since we're still well short of daylight duration
sufficient to incite these hormonal changes (which at these latitudes won't
occur for at least a month or two depending on species), we need to look for
another reason that birds sing in winter, a period I'd suggest stretches
usually from mid-late November to late February/early March at these
latitudes.

And how do we know that the birds singing in your area now are the same
birds as will be singing there in April or May? We don't, not without
banding the little blighters and putting locators on them to track them. But
the Song Sparrow or Varied Thrush you hear today, January 15, may call a
forest or a thicket in the Yukon or northern British Columbia its summer
home, or anywhere in between, and the singing bird you'll be hearing in a
couple months' time may currently be in Tucson or Point Reyes or losing its
shirt in Las Vegas.

Usually, the birds we hear singing at these latitudes this time of
year---even resident/non-migratory birds such as House Finch and Bewick's
Wren---would be asserting winter-territory possession of shelter and food
resources against their own and other species' claims rather than the
territorial/mate-soliciting claims we associate with true spring on
breeding-territory.

And, yes, many plants are blooming earlier than usual this January. Let's
hope they won't be chastised for their eagerness by second-half-of-winter
frigidity.

Michael Price
Vancouver BC Canada
loblollyboy at gmail.com

"I feel like a fugitive from th' law of averages!" -- GI Willie
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