Saturday, February 28, 2015

Crossbills to Cucumbers

The name red crossbill is an obvious fit, when looking at this male bird. The red crossbill's scientific name is Loxia curvirostra.

The females also have a crossed bill, but more of a yellow-green color. The website, All About Birds, implies that crossbills will reproduce at any time of year, when ever and where ever they find an adequate supply of cones and seeds.


These crossbills were found last week in the Arboretum. The morning air was cool and crisp as the birds silently searched for seeds in a western hemlock. The tree's scientific name is Tsuga heterophyllia. Given how quietly the birds worked, the key to finding them was the carpet of cones covering Arboretum Drive.


Pine siskins worked side-by-side with the crossbills. The beaks of the crossbills provide extra leverage, compared to the short, straight bills of the pine siskins. (The pine siskin's scientific name is Carduelis pinus.)


The efficiency of the crossbill beaks may explain why the two birds can feed in the same trees, get the same amount of nourishment from the seeds and yet the crossbills grow to be more than twice as large as the siskins. Crossbills and siskins are usually found near the tops of coniferous trees, where the greatest quantity of cones grow.

In this case, after feeding in the hemlock tree, the crossbills surprisingly chose to rest in the top of this deciduous, e.g. cone less, magnolia tree, Magnolia acuminata.

Further south in the Arboretum, this red-naped sapsucker seems to feed exclusively on sap from a single spanish fir tree, Abies pinsapo. Searching this big-leafed maple, Acer macrophyllum, for insects was the first attempt to vary its diet that I have observed. The scientific name for the red-naped sapsucker is Sphyrapicus nuchalis.

Near Foster Island, this stellar's jay, Cyanocitta stelleri, seemed a bit more committed to finding protein.

On Duck Bay, a wood duck, Aix sponsa, demonstrated how the idea of water skiing was most likely inspired.

Next to Duck Bay, a male downy woodpecker checks out last year's nest, in what is left of this red alder. Given the location, this is most likely the same male seen in last week's post. The scientific name for the downy is Picoides pubescent, the name for the red alder is Alnus rubra.

Last Saturday on Foster Island, a female pileated woodpecker searched for insects on this standing snag, which was once a white birch tree. The scientific name for the pileated is Dryocopus pileatus, for the paperbark birch it is Betula papyrifera

Thank you to Kathy for pointing out this bird!

It was only a short time until the male pileated, most likely Elvis, announced his arrival with his loud and proud call. In the near future the female will start spending her days sitting on eggs in the nest. The timing will be obvious, when we start seeing the male searching for food alone, we will know the nesting has begun.


The two woodpeckers spent over an hour working the trees and snags on both sides of Cottonwood Downs, the canal on the south side of Foster Island. It is wonderful for woodpeckers that the arborists leave standing dead trees in the Arboretum. If you would like to see woodpeckers in your yard, you might want to do the same. 


 
Elvis is probably more than a foot and a half long, which makes me think his shoulders could be 4 or 5 inches across.


This made me wonder, How do you measure a bird? Is it when he is stretching and extended to his longest possible length or…

 …is it a moment later, when he scrunches down to go after a tasty little treat.


Here is one more shot of Priscilla, as she levitates up the snag. Even if she is actually using a single toe for leverage, the power-to-weight ratio of a pileated woodpecker must be incredible.


At the end of the day, this young cooper's hawk surveyed the cattails from a cottonwood tree on the southeast corner of the Union Bay Natural Area. The Latin name for this bird is the easily remembered, Accipiter cooperii


 Nearby a river otter finds a bite of dinner…


…before disappearing into the cattails. Since the otter entered the cattails around dusk it makes me wonder if it is spending its nights there. On Thursday, my daughter's dog acted unusually nervous in this area, which is close to where the beaver has been playing lumberjack. The scientific name for a river otter is Lontra canadensis, while the scientific name for a beaver is Castor canadensis.

The title to this post was, "Crossbills to Cucumbers". The link to crossbills was obvious, but the cucumber link is a bit more subtle. I will wait until next week's post to explain the relationship. This will give you seven days to solve the mystery. Good Luck!

Have a great day on Union Bay…where nature lives in the city!

Larry

In Parting:

Which of the next two photos do you like best?

A.

B.
I am curious if living in the pacific northwest causes us to prefer the lichen or the blossoms. I seem to be leaning towards liking the lichen. 





Saturday, February 21, 2015

In The Mood?


Have you ever wondered if birds have feelings? While searching the moss for food, this female Downy woodpecker stopped and checked for danger. She seemed careful, maybe even regal, but there were no obvious signs of emotion.


The female, Downy Woodpeckers generally feed on the larger…


...lower branches...


…while the males prefer... 


…the smaller, upper branches.  When the males are away, the females will also feed in the upper branches. 

When this female encountered a male Downy, on a mutually desirable branch, her raised wings were a very visible reaction.

The male's response was just as strong. The birds attempted to intimidate each other, rather than exchange blows, which could cause damage. 


 The female "states her case" while…


 …keeping the branch between herself and the male.


The birds switched positions as they argued. When birds defend themselves, their territory or their nests they often elevate their crests, spread their wings and attempt to look as large as possible. Scaring the other bird away is the safest approach.

At this point, they have circled completely around the branch. Ultimately...


...the male retained ownership. The male's red crest was still slightly elevated, which seems to imply that he had not yet calmed down. It may be impossible to know exactly, what the birds are feeling, but this encounter looked emotional to me.


Surprisingly two days earlier, in the same trees, a male Downy shared the upper branches with these two females. Apparently, this was allowed because the females were not feeding. The females were chasing each other from tree to tree. 


Occasionally, they would stop and hold their beaks vertically, spread their tail feathers and sometimes their wings and... 


 then bob their heads from side to side. 


These displays seemed almost playful. Over and over, they chased each other to the next tree top and repeated the process. All the while, they stayed within eyesight of the male. This behavior may be a preliminary, female mating competition. It seems very similar to the way female flickers often behave in the spring. 


The male appeared to pay no attention to the females, as he fed.

For at least half an hour, the females moved back and forth. The one time that the females started to feed, the male immediately appeared. He shooed them out of the upper branches and then returned to his feeding. Apparently, he was watching them after all.


All of this happened in three or four trees next to Duck Bay. One of the trees contains a Downy nest hole, from last year. None of the birds inspected the nest or attempted to mate.  They may not be in the mood for love, but they certainly behave as if they have emotions.

You can see last year's nesting story by: clicking here

Have a great day on Union Bay…where nature lives in the city!

Larry

Please Speak For The Shorebirds:


Flocks of shorebirds, like dunlins, are amazing to watch in flight. The term for their naturally choreographed flight is murmuration. If you would like to see what they look like please check out this video

The current 520 mitigation plan will enhance the Montlake Fill, but it does not allow sufficient space for migrating shorebirds to feed. Because of this Connie Sidles, Dennis Paulson and the Seattle Audubon have started a petition to speak for the shorebirds. You can read more about their request for help, Here

At the very least, please join hundreds of others and sign the petition. It will only take a moment to let the Corp of Engineers know, you believe it is critical to include shorebird habitat at the Union Bay Natural Area.




















Saturday, February 14, 2015

Sex In The City

This bushtit may not have the bright colors of a hummingbird, the hair-raising call of a loon, or the fierce demeanor of a hawk, but she does not dwell on her shortcomings. 


With their nearly constant movement, bushtits do not dwell much at all. On the other hand, if we think of 'dwell on' as "having the ability to focus," then bushtits have exceptional concentration.


They are constantly twisting & turning and


...flittering & fluttering from one twig to the next, while they focus on finding their next mouthful of food. Bushtits weigh less than a quarter of an ounce. While I have no scientific proof, I would not be surprised if they eat their weight in insects every day.

Last week, at the Union Bay Natural Area, a flock of bushtits appeared just before sunset. 
The cold wind blowing off the bay ruffled some of her little downy feathers. These very fine feathers look more like hairs, to me.

Only their wing and tail feathers look like "typical" bird feathers. The bushtits swooped in as a cloud of gnats enveloped the willow trees, south of the main pond. As he sits in the sun, this little bird seems to sense the gnat below the twig. 

The bushtit appears to listen intently for the buzzing of the gnat's wings. It was surprising the gnat did not fly away.

Once the gnat stops moving, the bushtit loses interest and moves on. Did you happen to notice which of the birds were male or female? If you do not know how to distinguish their gender, the pronouns used above are clues.

Just like human males, hoping for a mating opportunity, a bushtit must keep up his appearance.

All the extra cleaning

...can be time consuming.

However, when you think... 

…you may fall head-over-heels for someone, the time spent can be worth the investment.

Bushtits seem to find communal life more important than being territorial or defensive.

In fact, this tiny pair appears to be mating, while sharing a branch with another pair of bushtits.

Afterwords, the female moves towards the warmth of the setting sun, while the male seeks warmth from the next bird on the branch. I wonder if the mating implies they have already built a nest nearby.

I have not yet had the opportunity to photograph a bushtit nest. From what I have read and seen, it is one of the most amazing, sock-like nests you are likely to see. My friends, Dan Pedersen and Craig & Joy Johnson, just completed a timely post about building bird boxes. Luckily, their post includes one of Craig's beautiful videos showing young bushtits and their nest. It is amazing.

You can see for yourself by following this link: My Joyous Winter Project

I would love to have bushtits nesting near my house. I never thought about all the materials they need to build their nests. It appears they use spider's silk, lichen, moss and various small, lightweight pieces of plants. Easily available materials should improve the odds of them nesting in my yard. In the future, I will think twice about what things "need" to be cleaned up.

By the way, did you know, you may be able to bring native plants into your yard and get a rebate for the cost? The plants would have to be part of a rain garden. It is an idea worth exploring. If you are interested, you can learn more about the rain garden program via SustainableBallard.

You can read more about bushtits and their nests on BirdWeb and All About Birds.

Have a great day on Union Bay…where nature lives in the city!

Larry

FYI:
The female bushtit has a yellow iris and a dark pupil.

The pupil and iris of a male bushtit are both dark.