Friday, May 21, 2021

Update On Montlake Cut Eagles, Marsha and Monty


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



Waiting

Where's the food?

In late March, one of the Montlake Cut adult Bald Eagles was in the nest. Since Marsha is the one who lays the eggs I suspect it was her. This year will be their fourth Spring of raising young on the southeast corner of Montlake Cut. From past experience, I generally assume our local eagles lay their eggs around the last week of March.

April was mostly a month of waiting. In this photo, Marsha appears to be sitting on eggs in the nest while Monty is standing guard. The Cottonwood tree is also waiting. It requires warm weather to induce its sap to rise and fuel a burst of green leaves and flowering catkins.

By the way, I call them Monty and Marsha because they have made Montlake Cut and Marsh Island the core of their territory. They defend this area that surrounds their nest, which is truly the center of their world.

By May, the leaves arrived and the unseen eggs had probably hatched. However, for Eagle watchers, the waiting continued. It takes time for a young eaglet to get strong enough, tall enough, and active enough to be seen from the ground. 

Early on, when the eaglets are very young, the parents seldom leave the nest unguarded. On warm days the nest may appear empty but usually, a careful search of the nearby Cottonwood branches would reveal a watchful parent half hidden among the green leaves or sometimes I suspect a parent was laying so low in the nest that they were not visible from the ground. 

On May 3rd, I got my first visual evidence of new life in the nest. Directly below the vertical branch in the background is a small, fuzzy, half-circle of white.

A split-second later the fuzz has moved and the adult eagle's head has turned to track the movement. This confirmed for me that there was at least one eaglet in the nest.

By mid-month, the eaglet had grown significantly. When standing its head was probably 4 or 5 inches higher. The young bird had replaced most of its white downy fuzz with what appears to be a nearly uniform blanket of grey feathering.

When feeding the parent tears off tiny pieces of meat and carefully "hands" the bite-sized pieces to the young bird. While the young one is consuming the previous morsel the adult will tear off another piece. Sometimes, if the nestling is not yet ready, the adult has time to swallow the food before ripping off another piece. 

Much of this process happens below the rim of the nest and it can be difficult for a viewer to determine exactly what happened. Is there a second eaglet in the nest? Is the adult eating some of the food or feeding another nestling? However, if there are multiple healthy young eaglets sooner or later they will both (or all) be visible at the same time. 

In the meantime, just seeing one gray fuzzy head sticking out of the nest is a heart-warming sight.

All About Birds states that the normal clutch size for Bald Eagles is from one to three eggs. It also implies that incubation averages around 35 days. So egg-laying during the last week of March and hatching in late April or early May seems likely.

Preening and cleaning their feathers is a critical survival skill for a Bald Eagle. Clean feathers shed water and retain heat plus properly aligned feathers enable flight and are fundamental to the Eagle's ability to catch prey and feed themselves - and their young.

For the young eaglet, preening is also important. Within the next few months, it will grow to be the size of its parents, while replacing virtually all of its feathers as it develops the ability to fly. This appears to require a consistent effort to help remove the smaller older feathers as they are pushed out by the new ones.

As the eaglet, or eaglets, mature and grow the number of creatures that could potentially harm them in the nest declines. The adults become more willing to leave the nest unguarded from time to time. In this photo, the adult in the upper right had just swooped at the duck in the lower right. The second eagle followed a similar course of attack, however, the duck avoided them both. 

On the other hand, an unlucky fish chose the wrong moment to come to the surface. The second eagle snatched it from the water and continued on to a nearby tree.

A couple of days later, on May 18th, the eaglet and the adult are very obvious in the nest. The whitish feathers on the eaglet's head have been mostly replaced.

The eaglet is hungry and the adult supplies the food.

Its demand for food seems nearly infinite. 

I find it interesting that young eaglets have no access to water during their first two to three months. They must learn to fly before they can learn to swim. Eagles do not dive underwater and their method of swimming looks more like rowing than anything else. You can see an example from last year by Clicking Here.

At this point, even though I had only seen one eaglet at a time it did not mean there was only one in the nest. The absence of data is not proof of absence.

However, a moment later two little heads popped up, both wanting food, I finally had proof of two eaglets. It always takes me a moment of staring at this photo before I can register and see both eaglet heads, one on each side of the adult. Their camouflage is quite effective. 

Of course, now the question is, Could there be three?

If there are three healthy eaglets sooner or later they will all be seen at once. 

All birds lay eggs sequentially. However, they are not always incubated sequentially. Wood Ducks will often lay an egg a day, with an occasional day of rest in between. However, they do not immediately start incubation. On about the tenth day they begin sitting on the eggs. That way all the eggs hatch out at about the same time. This makes it feasible for the whole brood to leave the nest at one time and for the mother to keep an eye on all of them.

The National Eagle Center says that Bald Eagles will lay an egg every other day or every third day. Apparently, Bald Eagle incubation begins as soon as the first egg is laid. As a result, each egg hatches on its own schedule with the youngest eaglet breaking out last.

The older and larger eaglets tend to demand and get more food which must extend and emphasize the size and developmental differences. One year, two eaglets at the Broadmoor nest fledged at significantly different times. The older one first flew from the nest in early July while the younger one was left behind did not fledge until early August.

From what I have seen the two eaglets in this year's Montlake Cut nest seem to be fairly close in size. It will be interesting to see how they develop and when they take their first flights. My current best guess is sometime in July.

I was surprised by the level of pin development and the size of flight feathers shown in this May 19th photo. While checking out these development photos my assumption changed a bit. I am currently thinking this eaglet may already be a month old. If that is true then its incubation probably happened a bit earlier than I assumed. Maybe this eaglet's egg was laid closer to the middle of March. 

Some fun things to watch for this year will be how the young eagles behave just before and after they learn to fly. Normally, I remember seeing young eagles spending a lot of time flapping their wings and developing their muscles before they attempt to fly. It seemed to me that last year's eaglet, Tsuloss, skipped much of that preparation and simply flew. Also, two years ago the Monty and Marsha's young often returned to the nest to eat - even after they learned to fly. Again, I did not notice that behavior with Tsuloss.

Giving these young birds names would be wonderful. Especially, if their names inspired hope for the future and harmony with nature. A future where all life, human and otherwise, is cherished and protected. It would also be appropriate if their names offered respect and honor to Native Americans, on whose ancestral lands, we all live.

Following This Link and scrolling down to the bottom of the page you will find the Lushootseed name for Bald Eagle. English seems inadequate for reproducing this word. Plus, we have two eaglets to name.

The Lakota name for Eagle is, Wanbli, and is defined as the one who flies the highest. The Ojibwe name for the Bald Eagle is Migizi. (My new Native American friends who taught me this word explained it is rude to point at a Bald Eagle. Their custom is to pucker their lips in the direction of the eagle to indicate where it is.) The Cherokee name for an Eagle is, Awa'hili, however, there are other symbols involved with this name that I do not understand. There are probably hundreds of other Native American names for Bald Eagles. I wish I had time to learn all the names and all the appropriate customs. 

Finally, it might be best to wait and watch before attempting to name these eaglets. In time genetics and gender will surpass the influence of birth order. Once full-sized, female Bald Eagles are noticeably larger than males. On the other hand, their names do not have to be gender-specific. 

The one thing of which I am certain is any names we attempt to give should be given with respect and awe. These are magnificent creatures who were here before humans and, if we can clean up the water and help the salmon to return and flourish, Bald Eagles should be here forever.
 and help the salmon to return and flourish, Bald Eagles should be here forever.


A few final eaglet photos:









 

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