Swainson's Hawks will start to fledge soon so I thought I
would share a little tip on one aspect of ageing them in flight. Of
course there are other ways to age Swainson's Hawks, but this is just a
note to share. Check out the contrast between the dark flight feathers
and the pale body on the adult (left) versus the juvenile (right).
Light adults have a much higher contrast to the underside (due in part to their darker flight feathers) than juveniles and
this is a good mark to look for on distant birds. Also, adults have a dark
tail tip and full "bib." Beware of one thing...although uncommon, some juveniles look bibbed similar to adults. Note the juvenile's fresh buffy plumage they show when recently out of the nest.
Mia, Thanks for sharing your pics with me...that is equally helpful! Let's get out with Ron when the Swainson's group together in August for some photos.
While really a biological questions, I'll pose it anyway: Fledging throughout their range? I ask because we've noted many pairs of Swainsons on the Texas-Mexican border who decided to nest here this spring. Owing to their short trip, I've been wondering if they fledged early. Rich in Texas
If I understand your question correctly...southern populations breed earlier than northern populations most times, so young leave the nest earlier in Texas than Canada for instance. Same with low altitude populations compared to high altitude nesters
An interesting post, Jerry. I'll be looking for some of the field marks you mention on our next trip to sw Montana where there are usually gobs of these young hawks this time of year.
The August plans to photograph these birds sounds good to me!
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I'm anxiously awaiting photographing this years Swainson's fledglings, they are incredibly beautiful.
Thanks for your earlier help in aging the sub-adult Swainson's I photographed earlier this month.
Mia, Thanks for sharing your pics with me...that is equally helpful! Let's get out with Ron when the Swainson's group together in August for some photos.
That sounds great Jerry!
Could I possible see these hawk in the English Road /RT 390 area ????
Do you mean 390 in upstate NY? If so, there are a few that go by on spring migration every year and likely fall too
While really a biological questions, I'll pose it anyway: Fledging throughout their range? I ask because we've noted many pairs of Swainsons on the Texas-Mexican border who decided to nest here this spring. Owing to their short trip, I've been wondering if they fledged early. Rich in Texas
Hi Rich
If I understand your question correctly...southern populations breed earlier than northern populations most times, so young leave the nest earlier in Texas than Canada for instance. Same with low altitude populations compared to high altitude nesters
An interesting post, Jerry. I'll be looking for some of the field marks you mention on our next trip to sw Montana where there are usually gobs of these young hawks this time of year.
The August plans to photograph these birds sounds good to me!
Thanks Ron
A good tip when they are high up or distant, among other clues.
We'll have to go to Snowville, remind me!!!
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