Wednesday, February 27, 2019

All About Eagles' Monty And Mary



Here is a recent post from the Union Bay Watch Blog published by Larry Hubbell, long-time local photographer and birder.

Here also is an in-depth article about Larry and his work.

Precarious
November 20th, 2018 was the first time, this winter-season, when I noticed Monty surveying the cottonwood branches. He appeared to be looking for candidates branches to use while building a new nest to replace the one which he and Marsha lost last summer.

By January of 2018, they had a visible start to their first nest. As you can see it was built out on the tree limbs, with the weight being indirectly transferred to the trunk of the tree.

By April the nest had grown significantly. Ultimately, one of the supporting limbs broke and the nest began to crumble. In the end, both of Marsha and Monty's young ended up at PAWS. Luckily, both of the juvenile eaglets were ultimately able to be released back into the wild.

This season, Monty is testing a new design. He has relocated about six feet lower in the same tree. The good news, he is using the biggest fork in the tree trunk. By the time of this photo, late November, he already had a half a dozen little branches balanced in the crotch of the tree. I doubt either half of the crotch will break this year, but this is no triangle of stability. The bad news, the new nest is simply balancing in the tree.

Having chosen their new location Monty and Marsha moved on to securing smaller branches and expanding the nest. 

Within two days, they had accumulated a dozen or more small branches.

When Monty is nest-building, his behavior is quite different. He spends less time sitting and searching the bay for potential meals.

He is more active. He flies from one tree to the next and then spends a good deal of time inside the canopy of the trees.

From there he searches for branches that are just the right size. If he picks a branch which is too large he will end up hanging upside down, unable to pull the branch free. If he picks branches which are too small, he will waste a good deal of time - making multiple trips back and forth to the nest site.

When Monty leaps between branches it seems quite odd to see his six-foot-wide wingspan extended inside the density of the cottonwood tree.

Although, I do find process rather picturesque. 

The golden yellow cottonwood leaves, the yellow of his bill and legs, plus his yellow irises almost feel like they are all color coordinated.

Some of the branches are thicker than others.

This particular branch initially caught hold and landed too high in the tree, near last year's nest site.

Monty struggled for quite a while trying to relocate the branch down to the new, lower nest site.

If I remember correctly the branch ultimately slipped from his grasp and fell to the ground, about the same time Marsha returned with a smaller branch for the nest.

The Eagles are continuing to work on the nest, but rather sporadically. It seems to me that they can't be too hungry and the weather can't be too cold. I must give them credit though, they are almost a month ahead of last year's schedule. If you are lucky enough to see them carrying branches back and forth across Montlake Cut, you should definitely stop and enjoy the construction process.

In December, I watched Marsha tugging on a stubborn branch on the north side of The Cut.

She is the bigger bird so it was not surprising to see her return with the larger branch.

Later, the sun broke through and the nest building continued. Monty returned with a branch which matched his capabilities.

On the afternoon of December 12th, for the first time, I saw both eagles sitting on the accumulated branches at the new nest site.

A month later, in early January, the nest had obviously grown. My concern for the nest's stability was also growing. Last week, I even got an email from a concerned neighbor who noticed the nest and mentioned that it looked rather precarious.

Here you can see Marsha residing in the nest.

The nest is perched in the fork with no other balancing limbs to keep it from tilting or falling. The fork is split to the east and west. As a result, the branches in the nest lay mostly along the north-south axis. Many of these branches have small branchlets. I have slowly come to the conclusion that the 'V' shapes, created by these branchlets are interlocking with the 'V's' on other branches. In addition, the accumulating weight of newer branches on top may be helping to hold the nest together.

I hope my logic is not just wishful thinking. I pray their construction technique is sound. For Monty and Marsha, their investment is not just in the nest building, Marsha must secure enough food to create eggs, they must protect and incubate the eggs until they hatch and then feed the hungry young for two or three months, until they finally learn to leave the nest and fly. At a minimum, this nest needs to survive for at least six months. Often, eagle nest's last for years and sometimes even decades. I sure hope this nest is not a precarious as it looks.



What species does the bird belong to? Is it native to Union Bay?


Ruddy Duck: These ducks are native to Western Washington and Union Bay. However, this is one of only a few which I have seen here. Females have the characteristic dark-line which bisects the lighter portion of their cheeks and both genders have the stiff little upright tail. This photo was taken last Tuesday, after our first snow storm, so the odd-looking reflection behind her is ice. For some unknown reason, she did not seem at all nervous about approaching me or my kayak.

Females do not have the blue beak or the brilliant 'ruddy' color of breeding males. 

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