[CT Birds] Morning flight and Bluff Point Groton, Part 1
davidprovencher at sbcglobal.net
Sun Aug 29 20:31:03 EDT 2010
Okay, it has been a busy day of taking my daughter Janet and her friend
Emily kayak practicing for in preparation for a kayak/camping trip to Selden
Island next month and this is the first chance I've had to post the info
people have been asking me about.
First let me differentiate between a good migration night and a good morning
flight at Bluff Points "Hot Corner," as they are not necessarily the same.
We are talking about night or "nocturnal" migration specifically. Nocturnal
migration has number of benefits. Its primary advantage is physiological.
Long distance migration is extraordinarily taxing. Great amounts of energy
is spent by these travelers. Flying is most efficient for these birds when
the atmosphere is cool and stable. Efficient flight is essential for
increasing survival rates, and long distance migration has a high mortality
rate. After the passage of a cold front, the atmosphere is cooler, more
dense, and usually more stable. Most of these marvelous little travelers
instinctually choose these nights to head south. Many birders think it is
the northwest winds that cause the birds to go. Well tailwinds are certainly
better than headwinds, but for efficient flight and successful navigation, a
light wind is better than a strong wind and calm is just fine as well. For a
good Morning Flight at Bluff Point, the winds MUST be northwest or calm. Any
wind that has an easterly component is not good, and any wind that has a
southerly component is extremely not very good! I am talking about local
conditions in southeastern CT here. So a good migration can occur with light
easterly winds or even light southerly winds, but the Hot Corner at Bluff
will be dead, bird-wise. This comes from years of experience, it has nothing
to do with radar or the actual number of birds moving. It's all about
migratory behavior, weather, and geography/topography.
I'd like to say one word about radar since it became a discussion point this
morning. In my opinion, radar is a wonderful tool, perhaps more of an
ornithological tool than a real help to birders. Now admittedly I'm a bit
old school, I use a map and compass in the wilderness rather than GPS. See
GPS can get you killed in the wilderness if you put religious faith in it. I
know someone who ran into a GPS believer in the White Mountains who was
walking down slope past the summit he was climbing looking for the peak. He
could see he was walking downhill but the GPS told him the summit was "that
way" and GPS couldn't be wrong, see he walked downhill away from the peak to
go up the mountain because GPS told him to! So if you know how to use maps,
and understand declination and magnetic anomalies, a map and compass will do
you fine. So to do I rely on my experience with weather, winds, bird
behavior, and Bluff, rather than radar, to judge whether to go there or not
on a given morning. And I am admittedly wrong sometimes, but usually only
when the winds are different than predicted.
On to Part 2.
Naturally New England
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