The one with a good view of parents fishing would maybe provide improved
chances of (long-term) survival for the young. At an LBL Eagle tour, I learned
that a very high percentage of young eagles do NOT make a successful transition
from being fed by parents, to hunting enough food on their own to survive.
From our excursion boat we saw one immature eagle trying repeatedly to catch a
coot. As the eagle swooped down, the coots simply submerged. They came back
up pretty quickly, but the eagle's trajectory had taken it past their location.
He had to perch and rest... and then he tried again. It was funny to watch,
but heart-wrenching to think this behavior may have been based on desperate
hunger. Anyone could see that he was never going to catch a coot, but he still
kept trying, wasting valuable energy.
Maybe we were just witnessing the standard 'learning curve' of a young eagle.
I hope he learned to catch fish!
It would be interesting to know if the 2-nest strategy is used by eagles on a
regular basis. Seems like it might have a natural selection benefit. Would
2-nest families successfully raise more young than 1-nest families? Just
having a backup in case a nest is lost to stormy weather would be a big plus.
Not to mention escape from parasites! And a good eagle's-eye' view of parents
fishing would be a major benefit, as well.
Sent from my iPhone
On Jul 12, 2015, at 11:19 PM, "Tina Nauman"
<tinanauman@xxxxxxxxx<mailto:tinanauman@xxxxxxxxx>> wrote:
About 6 weeks ago my favorite Bald Eagle's nest, with one eaglet, collapsed
after a week of heavy rain with the eaglet still in it. Luckily the eaglet was
able to get to a branch rather than falling with the nest. The property owner
found it perching unsteadily on a branch where the nest had been. I estimated
the eaglet was within 10 days of fledging so there was a very good chance for
survival. I was in Oklahoma so couldn't go check on it and was worried because
no one had seen it since the collapse. Saturday, with no rain in the forecast,
I made to the lake and was thrilled to find the eaglet getting soaring lessons
from mom, all the while screeching at her as it tried to keep up. One missing
tail feather seems to be the only sign of the event.
What I find interesting is that during the winter of 2013/14 a second nest was
built near the lake shore but never used for eggs. The original nest is very
secluded and out of sight of boaters but the newer nest is highly visible to
all on the water. Last year and this year, as soon as the eaglets fledged,
they moved to the newer nest and tree for feeding and as their nightly roost.
The eaglets got the benefits of a nice fresh nest, a view of the busy lake
beyond their secluded nest and could observe the adults fishing.
This nest was at least 10 years old and has been watched over by 4 generations
of the property owners. I estimate that it was 6+ feet across and research
suggests it could have weighed 1500 pounds. I hiked into the nest site and was
shocked to find only a few small sticks left in the tree and a massive amount
of sticks and grass at the bottom.
It will be interesting to see if they rebuild at the secluded site or use the
newer very public nest.
Photos here of the nesting season for this pair including post-fledge photos.
http://tinanauman.zenfolio.com/f396191263
Did I really say I have a favorite nest? I don't think so but it is the one
I've observed the longest.
Tina Nauman
Lexington, KY
