Monday, August 16, 2010

Update on the Golden Eagle Work

I mentioned in some previous posts (here, here and here) that I had done some work with the WA Department of Fish and Wildlife on Golden Eagles. Much of that work involved getting to eagle nests and removing any prey remains that were in the nest after the young had fledged. Today I got some the the results of that work emailed to me.
At one nest was the following: 1 coyote pup, 2 pheasant, 1 magpie, 1 crow.  The next nest contained: 3 yellow-bellied marmots, 1 hoary marmot, 1 deer fawn, 1 short-eared owl, 1 chuckar, 1 pheasant, 1 raven, 1 snake, and another unidentified bird.  The third nest contained: 2 coyote pups, 4 yellow-bellied marmots, 1 deer fawn, 1 chukar, 1 magpie, 1 rock dove, 1 snake.
The nest below had no above anchors and the rock below was of such poor quality that every time I tried to leave the ground I would end up pulling grapefruit size chunks of rock down.   I ended up climbing in from the ledge on the left of this photo and tunneling through a very small constriction on the far left of the photo after tossing a large pile of rock that was blocking my way.  Although the rope would have done very little to prevent me from hitting the ground if I was to fall I was more worried about the rock above collapsing as I crawled through. 
Here I am in one of the nests collecting prey remains.  Its also known as picking up dead things and putting them in a bag. 
 One nest still had a young bird in it and as I came to the nest that bird fledged. It was then captured, banded and fitted with a GPS tracking device.
Measuring the eagle before we carried him back to the nest. 

It was then carried back to the nest, but it decided it liked the outside world more and fledged for its second and final time later that day. The map below shows the movements of that bird since we fitted it with the GPS device. 
Courtesy of WA Dept. of Fish and Wildlife
There are many wind turbines in the area where this nest is so lets hope our bird manages to avoid the hundred or so that are there now and the hundreds more that are planned.

We also revisited the nest I placed a trail camera in earlier in the year.  This was to retrieve the trail camera which hopefully had been shooting photos of mother and two young birds for the last month of their time in the nest.  
Here are the birds when I visited the nest for the second time. 
The good news on this nest came before we got the ropes in place when a juvenile eagle flew right over head.  The great news came when we got home to find out there were 6000 photos on the trail cameras memory card and all but the last couple had eagles in them.
A photo from the trail camera showing mother bird, the two chicks and a coyote pup.  (WDFW Photo)
This is one of the last photos of the chicks in the nest.  The next morning they were both gone. (WDFW Photo)  

Although I have not been in that many nests I probably have the distinction of having sat in more of these (legally) than most other people.  The nest are huge, one which I went to was about 8 feet long and 6 feet wide.  The one in the photo just above was typical of sizes which is about 5 to 6 feet wide.  Not all of the nests are as stable as I would like.  I certainly never un-clipped from the rope while at any of the nests (with the exception of one which did not require a rope to get to, but turned out to be the most unstable).  I made the call that if it did collapse it would result in bodily harm but probably would not kill me.

All the nests I went to had several other nest nearby.  Eagles will often build more than one nest in a given area or on a cliff.  They tend to rotate from one nest to another over several years. The reason for this is not know for sure, but one theory is that parasites build up in the nest over several years and moving to other nests allows them to die off.  We did visit several tree nests which I did not climb to.  That was fun when I was a kid, now it looks downright scary.  Luckily I was with another person who was more that willing to climb tree nests.
Tree nest in Eastern Washington.
I usually don't like to create blog posts without a bunch of pretty pictures since that is what I am supposed to do, but I kind of felt the content of this post makes up for it.  But...  Here is a few pretty pictures just in case.  I shot these all in the last week or so.
Ravens don't often let you get this close. 
Closer still.  I only shoot with a 200mm lens. 

Juvenile Robin

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