Mission: To promote the appreciation of wildlife around Union Bay and harmony between humanity and nature.

(It is fine for educators and artists to use any of the photos on this blog as long as when publicly displaying the photo or related artwork the following comment is included, "The original photo sourced from http://unionbaywatch.blogspot.com".)

Saturday, March 21, 2015

Investment Versus Expense

This male cooper's hawk is looking into the future and making some tough choices. 

Not only must he select... 

 …just the right branches but… 

...he may also be wondering whether his nest building efforts are an investment or an expense. 

Those of us who are not accountants might legitimately ask, What's the difference?

Here is the first example that came to mind. When I was young my uncle introduced me to his grandfather, who had sold sewing machines to farming families, in the early part of the 20th century. Sewing machines were new and expensive, but the farming families could easily justify the investment. A machine would pay for itself, by saving time that would otherwise be spent sewing clothes by hand. 

When the traveling salesman bought his inventory, the sewing machines were an investment. The machines would eventually sell for more than the initial cost. The cost of feed for the traveling salesman's horse, which pulled the wagon that carried the sewing machines, was an expense. The feed did not increase in value, it was just a cost of doing business.

Male cooper's hawks often create more than one nest. Sometimes the extra nests are not even used. It makes one wonder why the hawks go to all the effort. Maybe they create the extra nests as a secondary option in case predators discover the first nest or the first nest is blown out of the tree. Maybe the extra nests are decoys to distract predators. Another possibility is, that an extra nest shows that the male has the energy and skill to provide for a growing family e.g. to attract a mate. A nest used to raise young is an investment, but the extra nests seem a bit more questionable. What do you think? Are they an investment or an expense?

By the way, the long feathers in the photo above are tail feathers, not wing feathers. 

Relative to other birds, the cooper's hawk has a very long tail that helps it maneuver between branches with ease. Here the male jumps off the nest, heading out to secure more branches, without even opening his wings. He uses his tail like a rudder to guide his body through the tangle of maple branches. The male always searches for small dry branches high in the trees. He never exposes himself to the risks, like off-leash dogs, that would come from picking up branches off the ground.

 While the male works at building the nest, a young female observes the process.

She constantly shifts position to keep the male in view while he flies back and forth between the nesting tree and nearby douglas firs or western red cedars. The coniferous trees seem to have much more brittle branches that are more easily removed from the trees. While watching the birds a piece of broken branch landed on my head and stuck in my hair.

The youth of the female is evident from the dark, vertical, teardrop-like, stripes on her chest. This indicates she hatched out last year and is in her second calendar year. Even though she is young, she is old enough to take a mate.

The more mature male has orange irises, instead of yellow, and reddish-orange horizontal bars on its chest. 

In this photo you can see that the male is wearing jewelry, e.g. bands around his legs. The female has not yet been banded.

Ed Deal has been banding cooper's hawks and peregrine falcons, in our area, for a number of years. The goal is to learn more about the birds and help them to thrive. Historically, cooper's hawks were shy and choose to stay away from cities. The last couple of years the number of cooper's hawks in Seattle appears to be growing. It seems like most parks, and even just neighborhoods with large trees, have cooper's hawks. 

(Just like barred owls, cooper's hawks also catch rats. Studies show that rat poison does bio-accumulate in birds and kill them. Rat traps are just as effective and much less dangerous to birds, pets and the environment.)

The key to tracking and learning more about the birds is the bands. Ed applies purple bands to the left leg of male birds. Orange bands are applied to the right leg of females. Both genders have metallic bands applied to their opposite leg.

There are unique codes printed on the colored bands. In this case the male has the code "3 over 3" on his purple band. This band was applied by Ed's colleague, Martin Muller, during the bird's first summer in July 2013. According to Ed's records, this bird was spotted again in August 2013 and then in October 2014.

If you would like to help track cooper's hawks you will need a pair of binoculars and a willingness to get a stiff neck while searching the tree tops. It also helps to listen for their calls. Ed sent the following set of links to help identify the calls of cooper's hawks.

An adult female: http://ibc.lynxeds.com/video/cooper039s-hawk-accipiter-cooperii/two-frontal-views-adult-perched-looking-around-calling-soft  A female will also make the "kekking" sound, like the males.

After you follow this link click on either "Food delivery to nest" or "Begging calls of chicks"

Now is an especially good time to watch for cooper's hawks because our big-leafed maple trees have not yet leafed out. If you spot a male bringing branches to a tree, I would be happy to pass new locations on to Ed, so he and his team are aware of the potential nesting sites. (My email is: ldhubbell at comcast dot net.)

All About Birds says, a study of cooper's hawk skeletons showed... 23 percent had healed over fractures to there chests. (Look under Cool Facts.) 

If you watch the way they fly between branches and around trees you will understand why.

The other day, while photographing a woodpecker, two birds flew past me very quickly.

They were way too fast for me to identify, but the first bird sounded like a very anxious robin.

They wove between the trees, with the second bird immediately behind the first. Given that we were not far from this nest, plus the speed and the close pursuit, I suspect the robin was fleeing from one of the cooper's hawks. They passed within 2 or 3 feet of me before disappearing into the underbrush. It made the hairs on my neck stand up. It also made me happy to be bigger than a cooper's hawk.

While writing, I just watched a crow breaking a branches off our neighbor's tree and flying away with them. Spring is here. Nest building is under way. We are beginning the most exciting time of the year! Hopefully, all the nests being built are wise investments, that pay high dividends.

Have a great day near Union Bay…where cooper's hawks nest in the city! 



By the way the PNW Nature Blog Scavenger Hunt that started last week has been extended through Sunday night. Last I heard, some of the prizes may still be available.

The goal is to answer a nature question on each of a variety of PNW nature blogs, just one question per blog.

The Union Bay Watch question is, "What treasure is scheduled to be hidden next to the ponds at the Union Bay Natural Area?" You will need to read last week's post to find the answer. You can scroll down or click the following link.

To learn the rest of the questions and the other nature blog locations please visit:


Monday, March 16, 2015

Hidden Treasures


This week Union Bay Watch is proud to participate in the PNW Nature Blog Scavenger Hunt. 

Your goal is to answer a nature question on each of a variety of PNW nature blogs, just one question per blog.

The Union Bay Watch question is, "What treasure is scheduled to be hidden next to the ponds at the Union Bay Natural Area?"

To learn the rest of the questions and the other nature blog locations please visit:


Northern Flickers tend to blend in with their surroundings. From the back, while working in your yard, they might even be mistaken for a large robin. 

When you stop and take a closer look at our most common Union Bay woodpecker, you notice the richness of the alternating colors. You see the tan-brown on the back and top of the head, the grey of the face, the off-white of the belly highlighted by the random but somehow uniform black dots and in the males you notice the bright red malar stripe.

From the front you can see the black crescent that looks like a dark bib. If you watch closely when the flicker flies away, you will see a bright white rump as they ascend into the foliage of a tree. However unless you watch very closely, you are unlikely to see the flicker's hidden treasures.

Our local northern flickers only display their orange feathers when competing for mates or territory. These displays happen quickly and are not aimed at humans, so capturing the colors feels like finding a hidden treasure. This female is hoping to gain the affection of a male.

The male is interested in something but…

 …the question is…

 …Is he interested in either one of the females that are attempting to gain his attention? As you can see in this photo, the undersides of their wings are also covered in orange.

Maybe the male was just playing hard to get, because when one of the females gets closer, he does turn and provide her with his own tail display.

Although hidden to the camera, it looks as though the female is responding with a similar display. The other female immediately springs into action.

She drops to a lower position and begins a nearly upside down display, which is clearly aimed at the male.

 Although she gives her best effort, the male seems mesmerized with the closer female.

When the first female decides to do an aerial display, the second gives up and leaves.

I wonder if the bright orange shafts, displayed on the top side of the tail feathers, are the source of the red-shafted name for our local variety of the northern flicker. If so, it seems like a more appropriate name would be an orange-shafted northern flicker.

The beautiful colors and displays of the mating process end in nest making, egg laying and raising young. The young in the nest are the flicker's ultimate hidden treasure. Can you pick out the hidden treasure in this photo? 

Around The Bay:

The shorelines around the main ponds, at the Union Bay Natural Area (UBNA), have historically provided food and rest for 29 species of migrating shorebirds. The planned 520 mitigation would cover and surround these shores with native plants, denying shorebirds a key stop in their migration. 

Click Here to read why local experts, Connie Sidles, Dr. Dennis Paulson and the Seattle Audubon, are against this portion of the mitigation.

Ironically, there are many other Union Bay shore areas which desperately need the native plants included in the mitigation plan

Examples include this shoreline on the southeast side of Foster Island (as pictured above) or the shoreline near the mouth of Arboretum Creek, which looks similar. These shores are covered with invasive ivy, holly and blackberries, unlike the shores of the ponds at the UBNA. The alternative shorelines would clearly benefit from the mitigation efforts.

Please sign the Seattle Audubon petition and ask the Washington State Department of Transportation (WSDOT) to relocate the 520 shoreline mitigation work, which is currently planned for the ponds at the UBNA. The millions of dollars being spent should be applied where the need is clear and uncontested. Speak up for the shorebirds by asking WSDOT, "Please do not hide the treasured shores of the UBNA ponds."

Click Here to see shorebirds in action.

Click Here to sign the Seattle Audubon petition.

Have a great day on Union Bay…where shorebirds hope to migrate!


Saturday, March 14, 2015

PNW Scavenger Hunt

This coming week Union Bay Watch is planning to participate in the:

The goal will be to answer a nature question on each of a variety of PNW nature blogs, just one question per blog. The hunt has been scheduled to begin on Monday at 8 a.m. and will run through Friday, 3-20-15. This Saturday's Union Bay Watch post is being delayed to coincide with the hunt. Please return on Monday to participate in the fun!

Saturday, March 7, 2015

Cartwheels In The Sky!

Two bald eagles surveyed Union Bay, from the top of a cottonwood near the Waterfront Activities Center, early Tuesday morning. Their calm acceptance of each other and their apparent need for companionship, seemed like the behavior of a mated pair. It made me wonder if we might not be adding another set of resident bald eagles on Union Bay. However, on closer inspection, their plumage indicated otherwise.

The eagle on the left still has traces of its dark juvenile beak showing through the yellow. In addition the iris of its eye is darker than the yellow of a mature eagle. Plus the head and tail are not completely white.

The eagle on the right looks a bit older. It has more yellow on both the beak and the eye and the breast is mostly dark, but the head is also not fully white.

When the bird, on the right, stretched its tail and wing, it became obvious that the tail is not completely white either. I am guessing these eagles are 3 or 4 years old.

The righthand eagle's immaturity was also obvious in flight.

The eye stripe looked almost comical, like a flying raccoon.

On the other hand, the claws are nothing to laugh at.

Lately, there has been a influx of immature eagles around Union Bay. Almost two weeks ago, this bird was seen perched above Arboretum Creek. I suspect it is younger than the eagles in the previous photos, due to the darker beak and less white on the head and tail.

Last Saturday, three young eagles with dark beaks and dark eyes visited Cottonwood Downs, on the southeast side of Foster Island.

With very little white on their heads and tails, and lots of white speckling on the bodies and wings, these birds appeared to be fairly young, 

I am guessing they are first or second year birds.

When a more mature eagle tried to scare one of them away, the three young ones turned the tables on the older bird, who settled for a perch further to the west. This older eagle appears to be more mature than all of the eagles we have seen so far. Still, the hint of darkness about the head and tail feathers, makes me think it may be newly mature e.g. in its first adult plumage.

I believe these sightings indicate the presence of 5 or 6 immature eagles, in addition to the eagle above. Hopefully, Union Bay is becoming a winter feeding and congregation site for immature bald eagles. Since these counts do not include the mature nesting eagles on Union Bay, like Eva and Albert, we may currently have as many as a dozen different eagles around Union Bay.

After an hour or so the eagle on the left, in our initial photo, relocated to one of the sequoia trees behind the Activity Center.

 The eagle's presence seemed to disturb the crows.

While the crows harassed the young eagle, a fully mature eagle landed on the top of the other sequoia tree, to the east.

Surprisingly, the younger eagle decided to switch perches and rushed the older eagle. Since the mature eagle looks smaller, I believe it is a male. 

The older, lighter and more agile bird chased after the crows before returning to the top of the other sequoia tree. Note: The tree with the larger cones is a Great Sequoia while the one with the smaller cones, to the east, is a Coastal Sequoia.

 Sadly, this did not stop the crows from harassing the younger eagle.

 The younger eagle gave up on the perch and headed south.

 As the eagle flew towards Montlake Cut, it watched another eagle approach.

Suddenly, the eagles grasp talons and the cartwheeling began.  If this is a courtship display the younger bird seemed decidedly unimpressed. Possibly, the fragment of feather on the older eagle's talon had something to do with the younger bird's apparent anxiety.

 (There was no time to cross The Cut for more favorable lighting.)

At this point the more mature bird rotated to the top. There are still a few visible tinges of darkness on the older bird's tail feathers, which presumably indicates its first adult plumage. This could be the same eagle seen on Saturday, on Foster Island.

 The cartwheeling continues.

The older bird dives toward the water. I have heard, once locked in each other's grasp, the birds may not let go until after they hit the ground.

Given how often the younger bird has its beak open, I suspect it was voicing a dissenting opinion through the whole operation. Once the talons are locked, I wonder if both birds must release their grip, before they are actually free from one another.

 They cartwheeled ever closer to The Cut.

 Twisting and turning as they descend.

 Eagles playing, Chicken in the Sky.

What if only one bird lets go?

Finally they parted ways.

The older bird circled and chased the younger one to the south before returning to perch on one of the sequoias. If this bird is searching for its first mate, apparently, it is still looking. I am hoping the process takes awhile and we get to see more of these courtship displays above Union Bay.


By the way if you missed last week's post from Dan, Craig and Joy, it is a very informative and enjoyable read, regarding Rufous Hummingbirds.


Also, last Saturday, I once again saw the tagged cormorant, ER4, at The Cut. This is the same bird seen early in February in the post, When the Fog Lifts.


The answer to last week's challenge is, the magnolia tree Magnolia Acuminate is commonly called the Cucumber TreeI hope you enjoyed the challenge.


Finally, as of this morning the Lichen is leading the Blossoms by a vote of 8 to 4. This is in regards to the question, Which of the next two photos do you like best?


I am curious if living in the pacific northwest causes us to prefer the lichen or the blossoms. I lean towards liking the lichen, but don't let that sway your vote. The voting is still open...

Have a great day on Union Bay…where nature cartwheels through the sky!