[Tweeters] Black Swift stuff 101
lpatters at ix.netcom.com
Wed Aug 24 16:37:22 PDT 2005
I realize that this is a very different kind of post and apologize in
advance if it's inappropriate.
I would like to attempt to foster so thoughtful cyberspace
conversation. Some of you already know all of this, but for others it
should be all new.
The Black Swift is one of North America's most poorly understood birds,
and what is known is a work in progress. Where these birds build their
nests is a lot of the problem. Danny Tyson found a Black Swift nest
near Mission, BC and writes about his discovery and the birds nesting
needs in a Spring 2004 Discovery Magazine Article.
"The nests are notoriously difficult to locate since the swifts have a
unique breeding ecology. All Black Swift nest sites must meet certain
specifications (Knorr, 1961). These include the presence of water, a
high location, inaccessibility to predators, unobstructed flyways to
and from the nest, and a situation protected from direct sunlight.
Thus, the nest sites are located on steep, sea-sprayed cliffs, in sea
caves, or at inland canyons near waterfalls. To make them a little
harder to find, the birds only return to these sites near nightfall to
feed the young."
It's beginning to look like the high location and unobstructed flyways
are perhaps not a must, and the lone baby swift can tolerate a bit of
sunlight, but what does seem to be vital is evaporating water very
close to the nest.
Why is this so?
No need to raise your hand. Just use your keyboard.
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