Autumn Hawks and Falcons

     On November 3rd, I headed south of Bellingham along Chuckanut Drive.  I stopped at Larabee State Park and observed a migrating Merlin falcon for 50 minutes, then I continued down through Bow and Edison to Bay View.  On Bay View Road I got quite a show of Red-Tailed Hawk and Northern Harrier activity, plus a Perched Rough-Legged Hawk.  Bald Eagles were not in evidence.

     Red-Tailed Hawks are by far the most common large (Buteo) hawk in our region.  Many times they get mistaken for other hawks, because they are so variable in coloration.  Perhaps this is because there are three subspecies that appear in our county:  the 'Western' regularly, and the 'Harlans' and 'Alaskan', occasionally.  Furthermore, there are sometimes intergrades when they cross mate.  Then there is the 'Gloger's Rule' which notices a tendency for more northern members of a bird species to have darker pigments.

     Another thing which can confuse beginning 'birders' is that immature Red-Tails do not have red tails, but dingy brown retrices.  The second picture is a juvenile and the third photo is an adult who has a partly amputated wing, so is 'retired' from the raptor business and is not in the education business.  Notice it has the mature red tail.

     Red-Tailed Hawks vary from almost pure white to almost fully dark, so how can you identify them?  One way is the dark patch on the leading edge of the upper wing (the patagium).  A second 'tell' is the dark belly-band.  Other ways I identify when they are at a distance is by perch stance, flight type, and their strong head profile.  When they fly, they make several strong wing strokes followed by a glide.  They are also great at soaring on updrafts.

       

Red-Tailed Hawk

Buteo jamaicensis

young Red-Tailed Hawk

Mature Red-Tailed Hawk

(non-releasable resident at Sardis Raptor Center)

Note the dark belly-band.

     At Larabee State Park I saw this small, male Merlin perched at the top of a dead Sitka Spruce.  He was ignoring fly-by songbirds and by the crop size, was quietly digesting a meal.  This was not one of the local 'Black Merlins' (Falco columbarius suckleyi).  They are much darker...so much so that the black malar mark (mustache) below the eyes is obscured.  You can clearly see the malar mark on this guy. 

Male Taiga Merlin (aka Boreal Merlin)

Falco columbarius columbarius

     The scapulars on Taiga Merlins are often slate colored or slightly bluish, if the light hits them right.  Taigas like this one summered in Alaska and will make their way down to Central America or even northern South America for the winter. 

     After watching him from 11:00 to 11:47, he looked directly at me, muted, spread his tail, head bobbed, and took flight to the south.  Of course, he knew of my presence the whole time and when he was ready to leave, we made eye contact, across 50 meters.

 

Merlin profile

(Note the distinctive head profile.)

Adult Male Northern Harrier

Circus cyaneus

Northern Harriers were patrolling the farmlands of Skagit Valley.  They usually fly 'low and slow', looking for voles and field mice.  This time, there seemed to be a preponderance of males and I noticed one chasing another.  The male adults are easily distinguished from the females.  Males are grey, adult females are orangish and brown.  The subadults of both sexes look much like the adult females and I am no expert at telling them apart.  A white patch on the upper rump can help you see these harriers from quite a distance.

Rough-Legged Hawk

Buteo lagopus

(Perched 300 meters away)

     Finally, perched above Bayview Road in the middle of the agricultural valley, I saw this Rough-Legged Hawk.  They are much less frequently seen than the Red-Tailed Hawks.  They are called 'rough-legged' because their legs are sheathed in feathers, above the feet.  You can see the dark feathers of this dark morph bird.  Its upper parts were mottled, but its belly was almost black.  After watching it perch and preen for about twenty minutes, it suddenly stooped on something in the adjacent field... probably a vole or mouse.

Thoreau's Legacy: Walden Pond

     Annie and I visited Walden Pond, Massachusetts, in late October.  This was the site of Henry David Thoreau's experiment in intentional living.  From 1845 to 1847, he lived close to nature in a self-built house.  During this time, he trained himself to be a naturalist.  Over the years he filled thousands of pages of journals with accurate observations of natural phenomena and after he read Darwin's, The Origin of Species, he conducted the first systematic, American field study based on the principles of natural selection: The Dispersion of Seeds.

     Though Thoreau observed and wrote everyday, he supported himself as a surveyor and by running his family's pencil and ink business.  He also lectured and wrote articles...especially on civil liberty and anti-slavery.  He was also part of the 'underground railroad', which helped smuggle escaped slaves to freedom.  To me, his legacy is environmental, scientific, and moral.  He was not afraid to speak out to set public prejudices and established interests.

                                Reconstruction of Thoreau's Cabin

Interior of Thoreau's cabin:  Thoreau said that he had three chairs - "one for solitude, two for friendship, three for society".

Walden Pond

It is almost a certainty that there would be no Walden Pond as it exists today, if Thoreau had not written Walden Pond.  Today it would be a developed suburb and business district, like nearby Framingham.

Predominantly Hardwood Forest Around Walden Pond

(Oak, Maple, Hickory, Beech, a little White and Pitch Pine)

Acorns

Poison Ivy

(an aggravating presence in eastern forests)

Beginning of Fall Colors

Red-Bellied Woodpecker

Cardinal

     Thoreau wrote about the pond always freezing over in the winter.  I talked to people at Walden Pond.  They said that last winter was the first time that the pond had not frozen over.  I talked to people in Maine who said that the tick problem has gotten much worse because last winter was so mild, that the ticks were not controlled.  I talked to people who regularly navigate the Potomac River, in Washington DC.  They said that the usual iceflows were missing last winter.  It used to freeze over.  I talked to a person from Indiana who complained about the horrible drought.

     I was wondering what Thoreau would say about global warming.  Actually, I'm pretty sure I know.

"If a few degrees more than our body temperature makes us ill, what of the earth."

           - Chaz Davies

"We cannot solve the problems that we have created with the same thinking that created them."

           - Einstein

"If we do not change our direction, we are likely to end up where we are headed."

           - Chinese Proverb    

     

    

"Who killed Cock Robin?" & Other Backyard Mysteries

By midsummer, the nests are abandoned and the fledgling birds are on their own.  I found this empty Robin's nest, while I was cleaning out my woodshed.  I knew that there had been a family of Robins in the shed and I had avoided bothering them until they had gone.

The structure of the nest is admirable.  Among the grasses and Red Cedar twigs that make up the majority of the nest, there are also pieces of garden twine and rope.  This nest fledged two young ones. 

Just two days ago. I saw a juvenile Robin investigating our blueberry bushes.  It figured out how to get under the 'bird net' and pluck a berry for itself.  I was impressed.

American Robin nest

Behind my house there are two mature Red Cedars, the scene of a little mystery.  The larger of the two trees is 113 feet tall (35 meters).*  As measured above the root swell at the base, the cedar is 16 feet in circumference and has a diameter of nearly five feet (1.5 meters).  Though a tree this size would not impress the first settlers of Bellingham, who regularly encountered giants that were 15 feet across, in present day, it is an impressive.  I estimate it is 80 to 100 years old, based on their tree rings usually being 0.5 to 1.0 centimeters thick.  (* using a clinometer, which translates degrees elevation into tangents)

Red Cedar (Thuja plicata)

     

At the base of the tree I found the remains shown below.

You may have guessed from the nursery rhyme title that they are what is left of a Robin.  This photo is of my original find, at the base of the south side of the trunk.  All the 'evidence' seemed close together on the ground, next to a root.  One feather was caught in a spider web above the ground.  You see above, a clipped right wing, the upper and lower beak, an unattached tail feather, an unattached primary flight feather, a smashed skull with the feathers attached, and part of the leg (femur and fibula/tibiotarsus).  The leg appears to have been eaten and later discarded or expelled.  Who killed the 'Cock Robin'?

Later, I found the other clipped wing on the west side of the tree and feathers on the north and northeast side.  This scattering is important in reconstructing 'who done it'.  

Our neighborhood is well patrolled by cats, but this wasn't a cat kill.  They leave a mangled, bloody mess, often accompanied by vomit.  Besides, our friendly, neighbor cat has been concentrating on rodents and bringing them to me as a 'gift': 2 rats, 1 mouse, and a shrew in the last two weeks.  This robin was neatly butchered after being caught.  It was beheaded (and the brains eaten).  It's wings were clipped, its larger feathers were plucked, and a leg was broken off.  This was the meal of a raptor:  either a Sharp-Shinned Hawk, a Cooper's Hawk, or a Merlin, which is a local falcon.

Who does the evidence point to?  Both the hawks and the Merlin have tomial 'teeth', a sharp bump on their upper mandible, used for beheading prey.  The clipped head does not point to one species over the other.

What about the position of the remains?  It seems obvious that the 'food prep' was done from up in the cedar.  The heavier pieces fell nearer the trunk and the lighter, free feathers drifted further away.  Feathers and wings were found on different sides of this large trunk.  A perch was used.  This points away from the Sharp-Shinned Hawk for two reasons.  First, "Sharp-shinned Hawks often sit on the ground where prey is plucked and then eaten." (Raptors of Western North American; Wheeler).  Second, Robins are the upper size range of what a Sharp-shinned Hawk will catch.  Larger females will catch a Robin, but not the smaller males.  Sharpies are going to start migrating south, starting this month and may be starting upslope toward the Cascades now.

Cooper's Hawks are rare in my neighborhood, though they are occasionally found in the region.  The fall migration starts soon for them (mid August) and they will be heading up the Cascades to catch the updrafts along the ridge lines.  I don't think it is a Cooper's Hawk.

I do know that our subspecies of Merlin (Falco columbarius suckleyi) take their prey to well-concealed tree perches to pluck or 'plume' their food.  They clip the head and eat the brain.  They clip off the wings and tail and eat the legs/feet.  I also know that where I live is well within the hunting range of our local Merlins.  They usually eat smaller birds and insects (swallows, sparrows, dragonflies), but they have been known to eat Robins.  Robins are at the upper limit of what they can catch and carry.  The males form a resident population and the females migrate.

I cannot be sure who ate the Robin, but the clues explained above lead me to believe the hunter was Merlin.  Investigating nature is often like this: putting together a circumstantial case from the available evidence.  

Lake Padden & Padden Creek, Bellingham WA

I. Lake Padden

Lake Padden is a gathering place for outdoor loving Bellinghamsters (yes, "Bellinghamsters").  Think of it as a more peaceful and wild version of Seattle's Greenlake.  Like Greenlake, it is a city park and a place of recreation.  It fits Bellingham's description of itself: the city of subdued excitement.  On this day, July 13th, there were kayakers, people fishing, swimmers, sunbathers, dog walkers (and a dog park), joggers, and people strolling or gazing out at the water.  The footpath around the lake is about 2.75 to three miles.

Unlike Greenlake, Lake Padden feels removed from the city.  It is girded and swathed by alders and willow and Mountain Ash (aka Rowan) at the lakeshore, and a forest of fir and cedar which rises up on the surrounding hills.

a fairly young Douglas Fir stand on the north shore

II. The Padden Creek and Trail

Several trails lead away from the lakeside. One follows Padden Creek, which flows from the west end  and empties into Bellingham Bay.  This is an easy, gravel covered trail which gives a beautiful sense of what a diverse, regenerating forest can be.  At this time of year, the creek is just a trickle of water, but it has cut an impressive gorge over time.

The forest along Padden Creek is a mix of Red Cedar, Douglas Fir, Western Hemlock, and maples. Many of the trees are young - evidence of past logging, but their are a few that are a meter across and must go back to the beginning of the last century or the end of the 1800s.

The canopy is dense and the light is filtered.  On a hot day, it is a peaceful oasis.

About a half mile (a km) below the lake, the creek and forest continue on the south side, but the north side of the trail opens up into tiny farms...the sound of roosters and tthe sight ofpastures.

The forested part of the trail ends abruptly and becomes an Inter-Urban Trail which will take you down slope to Fairhaven and the bay, while occasionally touching or crossing Padden Creek.

III. Canopy

Although many of the Red Cedar and Douglas fir are 25 meters (80 feet) tall, the Big Leaf Maple can also attain the upper canopy.  

As the name implies, the Big Leaf Maple is known for its huge leaves.  Some of these are as big as a dinner plate.

In the understory, there is a different species of maple, the Vine Maple.  This is one of the first trees to show fall colors each year.  Its leaves become a dark red or rich orange.

The forest floor has a luxurient covering of Salal and Sword Fern, both shown in the following photo.

 IV. Epiphytes and Nurse Stumps

Padden Creek Trail is a great place to see nurse stumps.  These are the decaying remains of old trees that give their nutrients to the new trees growing out of them.  There are also epiphytes everywhere you look along the creek.  Ferns and mosses cover the trunks and branches of trees.  This will give the walker a small taste of what they can see in the Hoh River Valley rainforest in the Olympic National Park.

Every stump becomes the soil and the substrate for its own garden.  This stump holds a miniature forest of huckleberry and moss and one oddly placed stone.

This nurse stump of dead Red Cedar has two trees growing out of it: a Douglas Fir on the left and a Birch tree on the right.

This nurse stump also has two trees of different species growing from it:  a Red Cedar and a Western Hemlock (on the right).  As these trees mature, the stump will be recycled.  It will gradually disappear.

This was an 'off-shoot' of the originally tree, which is now dead.  This one is particularly weird in its cantilever trunk...new life growing out of old.

Vine Maple growing from a nurse stump.

Padden Creek Trail is a beautiful, easy walk.  It is just one of dozens of city park, greenway, and inter-urban trails you can take in Bellingham.

Merlins: Branchers and Fledglings!

Merlin in Flight

Falco columbarius suckleyi

by R. Stillman, after a photo by D. Drummond

Part I:  Protecting the Nest

On June 27th, I joined David Drummond (Merlin Falcon Foundation) in field observations of Merlins.  Our first view of Merlins this day was of the female.  You can see her in these photos waiting for the male and the prey he would deliver to her.

 David Drummond and I found the feathers from previous prey deliveries: Vaux's Swift, House Sparrow, Cedar Waxwing, American Goldfinch, Barn Swallow, and Red Crossbill.  We also saw and heard other birds in this forest habitat: the singing of a Swainson's Thrush, American Robins, Winter Wrens (aka Pacific Wren), Bewick's Wren, and Red-Breasted Nuthatch.  There was a Hairy Woodpecker drumming nearby.  As I walked quietly near the prey delivery sites, I noticed the quiet agitation call of a Dark-Eyed Junco.  "Chip-Chip-Chip." (I must have walked too near to its ground nest.)  A Rufous Hummingbird buzzed by me, its wings making a sound like the sound that a card makes, when struck by the spokes of a spinning bicycle.  (Remember that trick?)

In this photo, the female has begun a long preening session, starting with the upper body and working down to her feet.

Preening under the right wing

Individual feathers get preened

Merlins recycle old crows nests.  This means that they often choose a nest near new crow nest sites.  There are many territorial squabbles at first, but by the time that the Merlins and crows are raising their young, they seem to have settled down to an uneasy truce.  At 11:05 I saw a sight that surprised me.  I saw merlins and crows cooperating against a common enemy.

A Bald Eagle flew within 20 meters of both merlin and crow nests.  The two crows and the female Merlin flew together and chased the eagle out of their territory.  The Crow-Merlin flight formation lasted only as long as it took to run off the bigger raptor.  They tail chased him out of sight.  I was astounded by the cooperation. 

Since the female was gone, the male immediately took over nest sentry duty.  Here you see the male, watching the nest and, of course, preening.  Notice the vibrant orange feet.  Females have paler digits.  

Notice the nicotating membrane (yellowish/pale), that closes during preening to protect the eyes.  

Here the male buries his beak into his breast feathers.  

This preen lasted from 11:25 to 11:45.  Here the Merlin's eyes are partly open.

Each wing was preened.

At the end of the preen, the male suddenly focused...

...and thrust himself into flight.

Part II:  Feeding Young

On July 3rd, David and I went to a different location and watched a male deliver prey to his nestlings.  If you look closely, you can see the passerine bird he caught, held in his taloned feet.

More often, the male would take the food to his mate, but this time she watched from another perch about a hundred meters away while he took the bird to the young.  She was making calls that would serve to distract potential enemies from what the male was doing.

After feeding them in the nest, he left and the young climbed out on a branch.  At this stage, they are called 'branchers' and will be ready to try their wings in a few days.  You can still see a little down on their heads, but they have their flight feathers.

The next stage for these youngsters is fledging and learning to successfully hunt.

III.  Fledging

On July 6 I went to the second nest site and it was abandoned.  On a nearby tree I saw one of the young merlins, now a fledgling.  It still had little tufts of down on the crown of its head.  The young must have fledged on July 4th (Independence Day!) or July 5th.  

This particular fledgling was perched in a tree normally used by the parents for food exchanges.  This was early morning.

This young bird is still dependent on its parents (despite the July 4th allusion).  They will continue to bring food for the fledglings; later showing them how to hunt dragonflies, then small birds.  Here you see the juvenile merlin pulling some cached food from behind the broken branch.

-temporarily satisfied, but ever alert-