Saturday, February 23, 2013

Elvis & The Red-Headed Relative

This week the chips fly as Elvis works hanging upside under a decaying log.
To view the video of Elvis at work, Click here. 


Nearby a redheaded relative works at a similar angle...
...however with a bit less force.

While clearly related these two are at the opposite ends on the Union Bay woodpecker spectrum. According to the Cornell Lab of Ornithology the Downy Woodpecker seldom weighs more than an ounce while the Pileated Woodpecker can weigh up to 12 times that amount. Cornell shows that the lengths of these birds do vary, however you can think of the Downy as being around 6 inches long and the PW as being roughly 3 times that length. Their wingspans have a slightly smaller ratio. The maximum width listed for the PW it is 29.5 inches while for the Downy the max is listed as 11.8 inches.

One way the two birds look similar is that they both have darker coloring on top of their heads, along their eye stripes and along their cheek (or malar) stripes. The red on the back of the head of the Downy tells us it is a male.

As mentioned in a previous post, the red on his cheek and forehead tell us that Elvis is male.

Another interesting difference in the two birds is the length of their bills as compared to their head sizes. This may seem like an odd metric however it can be particularly useful when looking at the Downy. In the case of the PW the bill is roughly the same length as the head. With the Downy the bill length is about half the head length. 


We have a third local woodpecker, the Hairy, which on first view looks a lot like a Downy. It is larger but in the field you don't always have the two side by side in order to compare. However the Hairy, unlike the Downy, has a bill that is roughly as long as its head. To see a very nice comparison, Click here.

Craig Johnson has done an amazing website all about our local woodpeckers. Follow this link if you would like to learn more.


After the video (Did you notice the chip falling onto his chest? Sorry, I just thought it was interesting.) Elvis flew to the ground to further inspect the chips he had knocked loose. During the process his head would disappear below the grass and then pop up as he checked for approaching danger.

In one case he came up with his eyes still closed. 
Note: This may not be an effective strategy for dealing with danger.
It seems obvious that PWs close their eyes to keep out the wood chips. However some folks think they also close their eyes to keep them from popping out of their head when they strike a tree or log.

Here is another shot showing Elvis with his eyes closed. It is from 2 weeks ago when he was working on the Empress tree.

There is no evidence of Elvis continuing to work on the Empress tree as described in the Danger in the Park post. For more about the Empress tree check out the Odds and Ends section below.

In closing here are a few more shots of Elvis's little redheaded relative.



Just in case you are wondering, the small white streaks in the photos are just a bit of Seattle rain. :-)

I think the buds in the photo however are another Sign of Spring.

Larry


Odds and Ends:

An interesting email from Arthur Lee Jacobson about the Empress tree.

Dear Larry,

Here is a May 7, 1998 photo I took of the tree. I used this in the second edition of my book Trees of Seattle. The flowers are edible, and sweetly aromatic. This individual tree specimen is about 80 feet tall, and dates from 1948. It is the largest in Seattle. You can use my photo if desired...

Arthur




Thank you to Arthur for a view from another perspective!

By the way here is another link I found about Arthur and his garden:

http://seattletimes.com/html/pacificnw/2011427334_pacificparthur04.html




Saturday, February 16, 2013

The First Sign of Spring

Not every bird comes to Union Bay, so sometimes Union Bay Watch goes to the birds.
These young Great Horned Owls were photographed earlier this week in the Nisqually Wildlife Refuge. GHOs are the most widespread owl across North and South America. Although only about half the weight of a Bald Eagle the grip of their talons at 300 psi is said to be nearly equal to the Bald Eagle's grip. At night the GHO is very close to the top of the food chain.

There are very few birds that raise their young in the middle of winter. Feel free to offer theories for why this happens in the comments section below, it could make for a very interesting discussion.
Even at just a few weeks old these birds are very alert. In this photo they focus and track a helicopter as it flies over. Notice the "horns", actually tufts of feathers, are erect on the bird to the left, this might be a reaction of alarm. Note: These horns are not their ears either. Their ears are asymmetrically located on the each side of their heads (See Update below) to allow them to "triangulate" with sound as well as sight. 
It can actually feel a bit alarming when their focus shifts to you...

...even when you know they cannot fly.

It is also interesting to note the difference in the size of the pupils. 
The bird on the left is focusing on something in shade among the trees while the bird on the right attempts to focus on the backlit helicopter. Obviously the wider pupils are drawing in more light. It would be very interesting to see the size of the pupils when these birds are hunting at night. 

Here is one more example.
The bird in front could be called, The Young Hunter, clearly the instinct is strong in this one.

These birds are so naturally fit to hunt that their tongues appear to be grooved to they can be used in combination with their beaks. They will become silent hunters in the night. Sometimes taking creatures that weigh more than they do. In these situations they may have to leave the body where it lands and then return to feed.

In spite of their hunting instincts right now these birds can look very young, soft, fuzzy and cute.
But they are growing wings that may end up spanning as much as five feet.
(Just like everyone else in the Northwest they have a "moss-on-the-roof" problem.)

In any case for the moment they can look very sweet.

In the next couple of weeks if you happen to find yourself south of Tacoma and passing by the NWR you should make the time to stop and check on these beautiful creatures. Soon they will be wandering out on to near by limbs and then spreading their wings.

Smile this is truly the first sign of spring!

Larry Hubbell

Note: I have heard of GHOs being seen in the south end of the Arboretum, although I have never seen one there. Feel free to let us know if you are lucky and happen to see one anywhere near Union Bay.

Updates:                                                                                                                  2-17-13

1) In the comments below Karen reports the owlets have left the nest and therefore are now fledglings.

2) I just saw a very well done video of the owlets. If you would like to take a look click on the link below:


Dan, Very nice work! Larry


Update:                                                                                                                  2-18-13

Peter Reshetniak, President of the Raptor Education Foundation ( http://www.usaref.org) sent in these comments.

"...Thanks Larry- is there a citation?  Wiki is a mile wide and inches deep on many things.  However, even this you can find  as per  hearing asymmetry in owls, and Bubo v. as well as Asio o. do not have asymmetry, i.e. both the Great-horned and screech have symmetrical ear placement (Payne, Roger S.. Acoustic Location of Prey by Barn Owls (Tyto alba). J Exp Biol. 1971; 54, 535-573 ) The owls with asymmetry appear to be the deeply nocturnal species, such as the barn owl..."

The answer to Peter's question is there is a reference however without access to the book I cannot be sure that the author was not misread or misquoted. The reference was, "Owls of the World by Konig, Weick & Becking. Yale University Press (2009), ISBN 0300142277".

"... I doubt that the PSI quote has any experimental data to support it (this is science by consensus ).  There is data on the dragging power of certain eagle species, plus the impact force is a simple mathematical calculation, but actual psi would require a very complicated machine to record the “crushing force.” and so far, I have found no such experimental evidence for any raptor.—whatever that is worth..."

The wiki reference for the 300 psi is,


"...As far as timing on egg laying, hatching, and fledging (all my intimate data is Colorado based) we will see 3 month variations in all of those categories with Bubo.  There is very little  “normal” in some things, as a wide variety of  unknowns, and knowns can change and alter some of those times/schedules.  I would imagine your part of the world is not much different.  The birds haven’t read about what they are supposed to do, or when they are supposed to do it.  Again,  if it is in Wiki, and if you cannot get a verifiable citation, and check the citation, it may be quite spurious.  I spend time in the Seattle area, and appreciate what you are working at, so watch Wiki as a source, it is quite broad, but its depth can hurt your head when you dive in..."

Thank you to Peter for the information and concern with the truth. In the future I will follow the links at greater length and look harder for the science behind the claim. Thank you especially for your knowledge about the timing of egg laying. It will be very interesting to follow up next year and see how much the timing changes. So much to learn and so little time. :-)

Larry













Monday, February 11, 2013

2013 State of the Union Bay Address

Union Bay is still beautiful and productive but it has changed. How did we get here?

Have we passed the darkest hour? 

History:

From the last ice age until about 150 years ago Union Bay was in a natural and sustainable state. The water level was higher which made the bay wider and the shoreline longer. The marsh area was also larger, so the population of local and migrating waterfowl waas most likely greater as well. The northern shore was somewhere between 45th and 50th streets. Spawning salmon would have returned to Union Bay via the Duwamish and the Cedar rivers, then crossed the southern portion of Lake Washington to spawn in Arboretum and Ravenna Creeks. Deer, elk and bear almost certainly roamed the woods around the bay. The bears, eagles and the Duwamish People were fed by the returning salmon. Most likely all five of the native species of salmon (ChinookCohoChumPinkSockeye) returned to the bay at different times of the year. The Duwamish People had longhouses sprinkled all around the bay. Their houses would have been built from the wood of mature Western Red Cedar trees, that most likely grew very close to where they were used. The air was crisp and clean and the water pure.

This can be contrasted with the state of Union Bay in the middle of the 20th century. The creation of the Montlake Cut (1916) was an economic boon that allowed access to timber and timber mills on Lake Washington, however it also lowered the water level by nearly 9 feet. This exposed vast areas of mud around the new, smaller Union Bay. This area was then used to store trash from the city of Seattle. Attempts to control potential flooding resulted in Ravenna Creek being routed in the sewer system and Arboretum Creek being forced into a culvert before reaching Union Bay. Reduction of water flow, pesticides, sewage and pollution from motorized vehicles (on land and water) stopped salmon from spawning in the original Union Bay watershed. DDT weakened the eggs of birds and resulted in reduced populations. Various introduced species, like bullfrogs and carp, also made it more difficult for native creatures to survive. Finally when the 520 bridge was built the untreated runoff was drained directly into Union Bay.

On the other hand during this "darkest hour" there were major efforts that mitigated some of the damage. The creation of the Washington Park Arboretum, the Union Bay Natural Area and the outlawing of DDT. Lead pollution in Union Bay was reduced first when hunting was stopped and later when lead was removed from gasoline. During the last few years Ravenna Creek has been partially restored and reconnected to Union Bay.

Currently:


The existence of eagles, osprey, peregrine falcons, pileated woodpeckers, wood ducks, hooded mergansers and trumpeter swans on Union Bay, to mention just a few of our favorites, is to a large degree because of the efforts and the accomplishments of our predecessors.

According to eBird during the last five years the average number of bird species sighted in the Union Bay Natural Area (UBNA) has been about 149 species per year. The highest count was 159 species in 2012. We cannot be sure why the increase occurred. People could be paying more attention or logging their results more often or there might actually be more species at the UBNA. However the good news is the species count does not appear to be decreasing.

There are three pairs of eagles nesting in the Union Bay area. There is a colony of Great Blue Herons that nest on the UW campus. Last year there were Pileated Woodpeckers and Barred Owls raising young in Interlaken Park and more in the Arboretum. 

There are now four beaver lodges in Union Bay. 
In the book "The Life of a City Marsh" the authors imply the first pair of beavers returned to Union Bay in the 1940s, most likely after being "trapped out" sometime earlier. Raccoons and coyotes seem to be thriving in the area. Not surprisingly deer, elk and bear no longer find their way to Union Bay.

On the salmon front things are a bit more challenging. Up until the last economic downturn introduced salmon did return to an artificial pond on the UW campus. Their eggs were harvested manually and "raised" indoors in trays of clean water. This was required because the water flowing out of Union Bay was and is too polluted for the eggs to survive.

The Future:  

Imagine all five species of salmon once again returning to Ravenna and Arboretum creeks. Imagine first grade school children watching salmon eggs hatch in their school aquariums and then taking a field trip to see their fry released into their local streams. 

Imagine in fifth or sixth grade the same students take a second field trip to the same streams to see their salmon returning to spawn. From a bridge they watch the eggs being released. They also see bald eagles swooping down to pick up the spent salmon. With binoculars they watch as the eagles return the salmon to their nests to feed their young. 

Imagine salmon being cooked on a piece of western red cedar in the same way the Duwamish People prepared their salmon for thousands of years. Imagine the students learning that this food is good to eat because it is once again free of pollutants.

Imagine that in middle school and high school the students return to the same streams to help protect and maintain the native plants that provide shade and food for the salmon and their young. Imagine these students being taught the environmental intricacies of the web of life that depends on the salmon and the wetlands of Union Bay. Imagine less pollution, less cancer and healthier lives for all the children living on and around Union Bay.

A few years ago this would have seemed like an impossible dream. Today parts of this  dream are starting to sound feasible. As part of the new 520 bridge construction the Arboretum Creek will be day-lighted. Wetlands damaged by the new construction will be replaced by new wetlands near by. The polluted 520 runoff will be routed into a settling pond and cleaned before it returns to Union Bay. We could potentially create even more wetlands by carefully sinking the old bridge in selected locations.

While this will be a huge step in the right direction there are other issues. There are things we can do as individuals and things we can do as a community. We need to reduce the pollution that runs off our houses, yards and streets, click here or click here to learn more. We need to plant more native plants in our yards and use less pesticides, to find out more click here. We need to increase the volume of clean cool water in our streams, click here. We need to monitor and reduce Combine Sewer Overflow near the mouth of Arboretum Creek and near the Yesler wetlands (east of the Union Bay Natural Area), click here. None of these issues are insurmountable. We simply need to be aware of our options and the impact of our choices. The future of our children and all the young on Union Bay is up to us. 

Thank you for caring.

Larry


Points in Time:

1854 - On July 4th Thomas Mercer states that someday Lake Ha-ah-chu (which he renamed Lake Union) will link Puget Sound to Lake Washington. This appears to be the birth of the idea of the Ship Canal and Montlake Cut.
1886 - Railway built along what is now the Burke-Gilman Trail.
1901 - Water from the Cedar River watershed is first used in Seattle. 
1907 - Green Lake is lowered and disconnected from Ravenna Creek
1916 - Montlake Cut lowers Union Bay & reroutes the drainage of Lake Washington.  
(There is a great 3 dimensional display at the new Museum of History and Industry that shows how Union Bay shrunk with this change.)
1926 - 1966 - Marsh areas around the bay were filled with Seattle trash.
1934 - The Washington Park Arboretum created.
194X - Hunting outlawed on Union Bay.
1948 - The rest of Ravenna Creek is diverted into the sewer system.
1963 - The original 520 Bridge was constructed.
1972 - Union Bay Natural Area created.
1972 - DDT outlawed.
1973 - Leaded gasoline phase out begins.
2006 - Part of Ravenna Creek is restored and it is reconnected to Union Bay.
2014 - 2016 Arboretum Creek is scheduled to be daylighted.

What is next is up to us.





Monday, February 4, 2013

Danger in the Park

Update:                                                                                                                   2 - 6 - 2013

Yesterday the following email was received from the Arborist at the UW Botanic Gardens. 

"Thank you for your concern regarding the woodpecker event. I was not in the office yesterday, so I apologize for my delayed reply.

Yes, we are well aware of the situation and have been monitoring for the past week.

Several factors go into a risk assessment regarding trees, wildlife and people. The health and vigor of the tree are taken into account. The potential for damage and the likelihood of that tree or branch failing are also taken into consideration. Lastly, the value of urban wildlife plays a large role in the management of the WPA. Mitigation options including pruning, cabling, or tree removal...or remove the target (trail and people).

In this case, the tree (Chinese empress tree) has been in decline for many years. The branch is probably more likely to fail due to the woodpecker, but I would still consider the risk to be moderate. In the past, closing and re-routing trails has limited effectiveness. Removing the entire branch removes the wildlife habitat (bad) and creates a large wound on the main trunk of the tree (also bad).

I prefer a pruning solution that retains the habitat, while minimizing risk to visitors. This type of pruning would attempt to mimic a natural branch fracture slightly above the woodpeckers feeding site. Pruning in this manner has been controversial as it does not represent a "correct" pruning cut in the traditional sense. However, I think it may be the best course of action in this incident.

Thanks again and I look forward to hearing your thoughts on this."

Clearly this is a well thought out attempt to balance all of the various factors involved. We are lucky to have the Washington Park Arboretum in such good hands. By the way if you have never seen this particular tree in blossom it is a beautiful site and worth a visit on its own. Here is a link to what I believe is a similar tree in blossom.

On a different note here is an interesting sequence of Elvis photos taken last Sunday.
In the first photo we can see how woodpecker feet differ from many other birds. Instead of having three forward toes and one hind toe the woodpecker has two toes in each direction. Clearly this increases the ability to grasp and hold from all directions. I am pretty sure I remember seeing a Pileated Woodpecker striking a tree with force while hanging upside  down which demonstrates the strength of its grasp.

When we were looking for Elvis the other day Doug Schurman mentioned seeing a PW throwing its body at a tree. This next photo, taken just a split second after the photo above, is clearly out of focus but it is does show Elvis leaping off the tree on the right and throwing himself at the tree to our left. Notice his wings are not being used at all. An eagle making a similar move would almost always have its wings extended for balance. He is completely at ease with the strength and power of his legs. 

A few moments later Elvis works his way up the tree searching for food. On these two decaying trees, just a few feet west of the Chinese Empress Tree, Elvis finds food on or near the surface of the tree.  As he works his way up the tree he uses his tongue to pick up additional food.
Once again you can see the use of the four opposing toes and how they grasp a fairly smooth surface with ease.

Have a great time in the park.

Larry

***********************

Prior Post:                                                                                                        2 - 4 - 2013 

Yesterday, Elvis was once again at work in the park. 

This time he picked a branch that actually extends over the trail to Foster Island.  The quantity of holes and wood chips indicates he has been working this tree for a few days. Some one passing by asked if Elvis was damaging the tree. It is true that his holes are weakening the branch and increasing the danger of it falling. On the other hand his reason for drilling into the tree is to get at the bugs that have been destroying the branch from the inside out. This means Elvis is, in effect, giving us a visible sign of the weakness of the branch. 

This evening a closer examination of the photo above revealed dark wood inside these two holes. This shows that this hollow portion of the tree has been exposed to air for some time. 
Most likely some creature, maybe carpenter ants, have hollowed out a sizable cavity inside this branch. The danger was here before Elvis began searching for food. His work has simply informed us that we should not be walking under this branch. This tree is located just north of the intersection of Foster Island Road and Arboretum Drive. 

Here is the same branch when approaching from the south.
There are a number of interesting photos from this encounter with Elvis that will be published later when time allows. Tonight the main goal is just to warn you to avoid this branch. The folks at the Arboretum have ben notified and I am sure they will take action as quickly as possible. Here is one parting shot of Elvis when he appeared to be hiding from some sort of danger. It seemed appropriate.

Be safe.

Larry



Saturday, February 2, 2013

A Mystery Bird

Birds tend to appear suddenly and then quietly disappear just as fast. If you visit one of our beautiful Seattle parks and this bird flies past, Would you know what type of bird it is? 
If this view of the bird is insufficient to identify the bird then consider what other information may be available to you. The coloring of the bird tends to blend in nicely with the dry grass, so it looks like it belongs in this habitat. Knowing where it lives tells us something about what it likes to eat. Grassland tends to support small rodents, mammals, insects and some small birds.

Historically, our mystery bird has been seen a handful of times in the Union Bay Natural Area, at Discovery Park and a bit more often at another Seattle park. Lately, there have been a number of sightings at this third location. Almost all of the visits have been during the late fall or winter. eBird shows no documented cases of this type of bird in Seattle in the summer.

If you would like a bit more information take a closer look at the next photo.
The brown bars on the tail and the cream coloring on the wing should help a bit, still a side view would provide even more information. 

That flat face is a real give away isn't it? We are clearly looking at some type of owl. The question is which type? The body coloring is not barred enough to be a Barred Owl.
Plus the Barred Owl tends to hunt among the trees more than the open spaces or fields. 

On the other hand the coloring is a bit too dark when compared to the Snowy Owl.
The owl we are focused on is by far the most active of the three owls. It will spend hours circling and turning just a few feet above the grass in an open field. It seems as though it usually keeps one wing parallel to the ground while using the other wing like a rudder. In addition it constantly alternates which wing is parallel and which is up in the air. 

It will dive repeatedly and only occasionally will it actually catch its prey. 
However this approach has turned out to be very effective as this bird, including all the sub-species, is found in North America, South America, Asia, Africa, Europe and even in Hawaii. 

Our mystery bird is the Short-Eared Owl (SEO).
The small ridge of feathers sticking up on top the head is what gives the SEO its name. However they are not ears and in fact they are not usually visible. Yesterday, one of these birds was seen by Doug Schurman at Magnuson Park. It might be worth it to take a walk in the park.

Here are a few more shots to help inspire you to get out into the cold and the fog.

Aren't you glad you are not the small creature at the other end of that focused stare.


By the way Marcus Roening, my master birding friend, was the one who first took me to the fields near Stanwood, where many of these photos were taken and he continues to inspire my birding efforts today. If you are up for a road trip the large open areas near Fir Island and Eide Road provide many excellent Short-eared photo opportunities.

My true hope is that we all get a chance to see the Short-eared Owl right here in Seattle.

Good Luck!

Larry

Odds and Ends:

For those who realize a bird must eat, here is an early attempt at video that turned out to be slightly out of focus, which actually makes the viewing a bit less graphic.


***

In the Comments below Penny mentioned that the SEO can make a sound similar to a dog barking. Here is a link to the Cornell site, the second sound track is as Penny described it.