Mission: To promote the appreciation of wildlife and increase harmony between humanity and nature.

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Monday, April 22, 2019

The Osprey Fight On

In 2016, for the possibly the first time in one hundred years, Ospreys successfully nested near Union Bay. Although, they did have to overcome some challenges. (Sadly, in 2018 their challenges took a new twist.)

In 2016, the Ospreys put a tremendous amount of work into their initial nest site. Unfortunately, the location, above the entrance to the new University of Washington Baseball field, was not acceptable. The nest was dismantled, prior to eggs being laid. Luckily, the UW athletic department paid for a nesting platform in the Union Bay Natural Area, right next door.

To the amazement of many, the female Osprey took the hint, settled down on the new platform and laid her eggs. Due to the time pressure, the nest was fairly sparse.

In spite of the minimal nest, by late August, they had three healthy offspring. In this photo, the adult female, who I call Lacey, is on the right. Her name was inspired by her brown 'necklace' which decorates her chest. Here it is easy to notice that the three young birds have dark feathers with beautiful white tips, unlike Lacey's more uniformly dark adult feathers. 

In July of 2016, I happened to catch this photo of Lacey and her mate, Chester. Chester's name was inspired by the fact that male Ospreys generally have pure white chests. This photo, with both adults looking down, gives us a chance to view the crowns of their heads. Later, I would learn that their crowns can be uniquely patterned. In this photo, we can see that Lacey, on the left, has more dark feathers on the top of her head, as compared to Chester.

At the end of each summer the Ospreys head south to warmer weather, most likely Mexico. Whenever it is warm the fish stay closer to the surface, so migrating helps the Ospreys to catch an adequate supply of winter food.

The Ospreys returned in the Spring of 2017. Even from a distance, we can see that Chester has visibly more white on the crown of his head. Although I find the markings on their heads adequate to tell the two of them apart, I am not 100 percent positive that I could successfully use the markings to identify them from other Ospreys.

In 2017, unlike the year before, they were able to focus on their nest on the pre-built platform. As a result, they built a noticeably taller nest.

During the summer, Chester worked hard and the nest continued to grow.

He also brought plenty of food back to the nest. The Ospreys successfully raised two young in 2017.

In 2018, they returned and clearly had every intention of raising young once again.

It is interesting to note that in May of 2018 the number of sticks in the nest was only half as high as in 2017. Lacey laid eggs and two young birds hatched out. Sadly, one disappeared early on and the second died later in the summer. The story of their demise was covered well in a Pacific NW Article by Glenn Nelson. If you click on the highlighted link you can read Glenn's story and you can also see that the sticks in the Osprey's nest never attained the height or depth that they did in 2017.

The experts suggest that the young birds did not get enough food. Since Bald Eagles steal fish from Ospreys, and a new third pair of Bald Eagles began nesting on Union Bay in 2018, the Eagles may very well have thrived at the expense of the young Ospreys.

However, there could have been other factors as well. For instance, what if Chester was replaced by a less-skilled male in 2018. How would we know? Last year, I could see that the male had less white on the top of his head than his mate, but was he really the same male from the prior year?

Here is a closeup of Chester in 2017.

Here is the 2018 male.

While light, shadows, angles and even the wind can change how feathers look. When I look close, the markings on the forehead and crown look different to me. Still, I am not completely positive. Ospreys mate for life and can live for a couple of decades. At the same time, a single mistake while diving headfirst after a fish could easily be fatal. 

The good news is, the Osprey pair returned last week. They were even seen mating. (Thank you, Ronda!). One way or the other, hopefully, this year's male will be a stronger and more adept provider.

In addition, a few days ago we watched Lacey chase away an adult Bald Eagle.

The Bald Eagle landed south of the Conibear Boathouse and then proceeded to chase after two immature eagles. I suspect one of the immature eagles might have been carrying a fish. 

Immediately thereafter, the adult eagle could be seen carrying a fish back towards the Talarus eagle's nest. I suspect the adult took the fish away from one of the young eagles. I believe he was the male bird, that I call Russ, because this time of year the female eagle would most likely be incubating eggs at mid-day.

Even though Russ was not an immediate threat, Lacey decided to let him know he was passing too close for her comfort. 

Given that she is probably half his weight her mid-air attack was quite impressive.

For good measure, she also chased off the two immature Bald Eagles.

A couple of days later there were a few more sticks on the platform. It may be the tiniest of encouraging signs. Still, the Ospreys have returned, as opposed to relocating to a new nesting site. Plus, Lacey is showing her tenacity and desire to retain her Union Bay nest site. At this point, it feels like all we can do is hope.

However, given that Ospreys eat fish, we can try to help the local fish population, which would indirectly benefit the Ospreys. One immediate opportunity is to minimize our usage of the 520 bridge. Currently, the runoff from that section of the bridge, directly above Union Bay, drains directly into the water. Automotive runoff is apparently unhealthy for fish. Healthier fish will reproduce more which in turn should mean easier pickings and less competition for our local, fish-eating Ospreys.

Have a great day on Union Bay...where nature competes in the city!

Larry


Going Native:

Without a well-funded Environmental Protection Agency, it falls to each of us to be ever more vigilant in protecting our local environments. Native plants and trees encourage the largest diversity of lifeforms because of their long intertwined history with our local environment and native creatures. I have been told that even the microbes in the soil are native to each local landscape. My hope is that we can inspire ourselves, our neighbors and local businesses to respect native flora and to support native wildlife at every opportunity. I have learned that our most logical approach to native trees and plants (in order of priority) should be to:

1) Learn and leave established native flora undisturbed.
2) Remove invasive species and then wait to see if native plants begin to grow without assistance. (If natives plants start on their own, then these plants or trees are likely the most appropriate flora for the habitat.)
3) Scatter seeds from nearby native plants in a similar habitat.
4) If you feel you must add a new plant then select a native plant while considering how the plant fits with the specific habitat and understanding the plant's logical place in the normal succession of native plants.

My intention in my weekly post is to include at least one photo each week and visually challenge us to know the difference between native and non-native lifeforms.








Is this a native or non-native type of flora?












Scroll down for the answer.














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Pink Flowering Dogwood: It is non-native, but related to the native, Pacific Dogwood

















For more information about native plants visit the Washington Native Plant Society.




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The Email Challenge:

Over the years I have had many readers tell me that Google is no longer sending them email announcements regarding my posts. Even more frustrating when they go to 're-sign-up', hoping that will enable them to once again start receiving the announcements, they get a message which says 'Sorry, you are already signed up.' Google has not responded to my requests for help with this issue. 

My functional workaround is to set up my own email list and each week I manually send out a new post announcement. If you are experiencing the issue and would like to be added to my personal email list please send me an email requesting to be added. Thank you for your patience!


My email address is LDHubbell@comcast.net

















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