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

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Saturday, October 31, 2015

Waste Not, Want Not

Last July I was lucky enough to watch this young cooper's hawk attack its food with vigor.  This was a bit of a surprise because...

...a few minutes earlier the young hawk had stopped eating. Its crop, the bulging area just below its face, was at least partially full. However, it kept one foot on the remains of its meal and called out as if to say, "This is mine, all mine." This show of possession was no doubt motivated by its two siblings who were hungrily pacing back and forth in nearby branches.

It is hard to eat when you are feeling full, so the young bird moved a few inches away and began to relax. First it stretched its tail and then its wings.

This was followed by closing its eyes and beginning to digest the meal. The remains of which are hidden in the maple leaves on the right. In spite of the temptation, neither of its siblings were brave enough to steal the remains. These three siblings are the same birds mentioned in the earlier post entitled, Fear and Trembling.

After a brief respite, the young hawk returned for more. Spreading the wings and tail to hide its food is called mantling. This must be partially instinct, as the bird clearly knew that its siblings were aware of the food. 

In this case, the mantling lets us see the length of the bird's tail feathers. Their long tails enable cooper's hawks and their doppelgängers, sharp-shinned hawks, to twist and turn with precision and speed as they pursue prey through forests thick with branches, leaves and trunks.

It also shows us the white tips of the tail feathers. Ed Deal pointed out that over time this white wears aware. In mid-summer the crisp white color indicates a young bird, hatched in the last few months.

After a moment, the bird becomes focused on food and forgets all about mantling.

The scent of the fresh meat, just like salmon on the barbecue, attracts wasps. The wasp about one inch in front of the hawk's nose seems particularly brave.

This summer I watched wasps near cooper's hawks at least three different times. In fact, one cooper's hawk nest near the top of a fir tree may have been partially protected by an active wasp nest two-thirds of the way up the same tree. Maybe it is a symbiotic relationship. My theory is that the wasps feed on the hawk's left over scraps and in turn they discourage predators who might attempt to rob the nest. I would be curious to hear if anyone else has also observed this relationship.

Maybe the wasps inspired the hawk's siblings, or maybe their hunger made them bold, in any case they finally decided to try and find a place at the table. Here it is easy to see the white spots on their backs, which as Penny Lewis pointed out, are also indicators of their youth.

I do not think this extension of the wings is an attempt to hide the food. I suspect it is an intimidation tactic being used to try and keep the siblings at bay.

The mantling and calling out did resume. The siblings stayed in the same tree, but at least moved off the immediate branch.

At this point, the uneaten portion of the meal had been reduced to scraps.

The satiated young hawk steps off the food, while the wasps attend to remnants on its claws. Evidently, feeling too heavy to fly, the bird waddled away to the far end of the branch. 

One of its siblings immediately darted in, grabbed the remains and pulled it towards the trunk of the tree. Shortly, there was nothing left, except the stain in the moss. In nature, there is no waste.

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A Note For Harmony:

Cooper's hawks eat a variety of small creatures including birds, squirrels and rats. Rodenticide can bio-accumulate in predators and lead to their demise. Old-fashioned rat traps and a spoonful of peanut butter are perfectly effective, and save the hawks. The hawks can then catch more rats! Go Hawks!

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

Larry

Silhouette Challenge:

Can you determine what type of bird this is? The answer will be in next week's post.

This photo, from last week, shows a downy woodpecker. The keys that help with identification are:

 a) The bird is using its tail for support against the vertical trunk of the tree, so it is most likely a woodpecker.

b) The beak being shorter than the width of the head means, that in our area, it is most likely a downy woodpecker.

Saturday, October 24, 2015

Trick or Treat


Do you see a trick or a treat when you look at this photo? I can see beauty in the shape of the crow's wings and the wide fan of the tail feathers. However, somewhat hidden in this photo is evidence of a darker side of crows.

This week I was attracted by the loudest cacaphony of crow calls I have ever heard. It was not the usual sound of a dozen of crows harassing a perched predator. Nor was it the peaceful sound of crows gathering to roost for the night. The pine trees in the Arboretum were full of forty or fifty crows, calling chaotically. The noise was almost deafening.

From a distance they seemed oddly focused on the ground. As I approached, I noticed a crow on the grass. Initially, I wondered if I was observing a crow funeral.

Taking a closer look I realized there were actually two crows rolling around in the pine needles. 

As the birds shifted and struggled, it became obvious they were fighting.

 I had never before seen crows in combat.  

Ironically, a few days earlier I had just responded to a reader who asked, "Is nature cruel or is it just the crows?" This was after crows had consumed a robin's eggs out of a nest in her backyard. The essence of my response was,

... From the crow’s perspective, they simply found food when they were hungry. Still, I am sure, the experience was painful for the mother robin. If she could talk she would no doubt call the crows cruel. I do not believe the crows ate the eggs in order to take pleasure in her pain. I suspect eating the robin’s eggs felt similar to a human having a ham and egg breakfast...

...If the robins had no predators they would reproduce without end until they ran out of food, mostly worms, insects and small fruit. The next generation of eggs might hatch, but lacking food most of the nestlings would slowly starve to death. Then the few who were lucky enough to survive would simply cause the cycle to repeat, endlessly. This would not be pleasant. Predators keep the population under control by eating the individuals, or their eggs, that are easiest to consume. This causes the prey species to become more intelligent about hiding themselves or in this case, their nests. The mother robin’s pain should motivate her to build her next nest, in a more hidden location. We are just beginning to learn that the knowledge from these types of experiences can be passed from a parent to an unborn offspring for multiple generations, as a result of epigenetic changes. Over millions of years this same type of encounter has been repeated over and over. The prey creatures that were smart enough to find better and better hiding spots have survived. This pruning of the ancestral tree of life is what has caused intelligence to evolve, in the form of crows, ravens and especially humans...

I was stunned to see crows at each other's throats. Clearly, they were trying to do each other harm. I had no way to tell if they were intending to be cruel. I do not even know why they were fighting. Was this a mating competition, a territorial dispute or a response to some sort of insult, like road rage fallen from the sky?

It appeared to me that the other crows were trying to persuade them to stop, as opposed to cheering on the fighting. Still I can't be sure if I was truly understanding the crows intentions or projecting my own thoughts and feelings. 

A few crows gathered closer.

The intensity of their concern seemed evident, although their interest in the well-being of the brawlers appeared to be offset by fear.

The birds on the ground were totally absorbed in their struggle. They ignored everything around them. 

My attention was also consumed by their struggle. I had no idea that a gardener was approaching from the opposite direction.

The battle continued.

Finally, one of the surrounding crows made a physical attempt to intervene.

The intervening crow pulled on one of the combatants.

The effort failed to stop the fighting.

At this point the gardner threw something in the direction of the crows. The pair took to the air and the whole flock dispersed. Clearly, nature has two sides. Nature provides both sunshine and darkness, sickness and health, life and death and in this case both competition and compassion. 

Only by fully understanding the complexities of nature can we be sure that our actions are harmonious, positive contributions to the future of life on earth.

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More Crow Stories:

Two week's ago I asked readers to share their experiences with crows and the foods they eat. I hope you enjoy reading the responses as much as I did.


From Bill Anderson, Edmonds:

...I once saw a crow flying off with a garter snake in its bill. 


From Susan,

Just read the latest Union Bay blog about crows. There's a really wonderful essay by Ian Frazier on crows from a few years back that you should find and read (if you haven't already)...


From Brenda Burnett,

I've also seen crows scavenging on the beach, flying up and dropping a shelled treat to break it open like gulls do. I appreciated the info on crows picking up dead sticklebacks off the water. I saw that on Union Bay a couple of years ago and wondered if that was unusual at all--wondered what had killed the fish, especially. Sounds like an annual event...


From Jackie in Sammamish:


I have 4 crows who live and dine in my yard next to a wetland in the Sammamish Plateau.  The first pair bred in 2013 and now the 4 crows have become bullies in my yard.  They have become a nuisance at my suet feeder which I have used for 12 years to feed flickers, downey woodpeckers and pilated woodpeckers (whose families have grown and come back to learn to eat every year).

I have attached 3 squirrel baffles surrounding the suet feed on a high hooked pole.  One baffle is directly below it, the second is attached at a side angle with masking tape to the pole, and the 3rd baffle is hung upside down below the suet feeder.  The crows have learned to fly aside the baffles to peck at the suet so they and their crew can feed below.

I have 2 bird baths which are cleaned every day because the crows drink, bathe and wet their suet lumps in them.  The crows are very smart and seem to defeat every suet protection I create.  (By the way, duct tape will not stick to plastic baffles - you have to use plain old masking tape in vast amounts.)

The 4 crows sit on my upper roof gutter and wait until they see me in the kitchen early in the morning, and then they bang the gutters with their beaks, waiting for me to refill the suet feeder as well as toss out apples for 2 orphaned fawns who graze in dry and cracked ground in the wetland due to the drought this year. .  They also peck at the apples.

My flickers, downey and pirated woodpeckers attempt to feed at the hung suet feeder but the crows attack them immediately.  I have several generations of each of these magnificent woodpeckers/flickers and am sorry they have stopped coming to my feeder.

I have tried many things to get them to move on, fearing that next year there will be 6 crows.  This family of 4 doesn’t seem to belong to any larger group of crows in the area which I hear in the woods.  They even have figured out how to land on the blue recycling bins on trash day and peck at the slit below the usually cracked lids of my neighbors bins  to access any tidbits they can drag down the street and eat any scraps.  They love pizza boxes which end up on the street where the 4 congregate to feast on the smears on the lids.

The crows constant noise annoys my husband and next door neighbors but I am intrigued with them, as much as I wish they would move on.

The crows also peck at the rabbits who dine on our organic lawn and especially when the rabbits have discovered apples thrown in the wetlands for the orphaned fawns.

Good luck with your crows.

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Happy Halloween! Hopefully, we will all experience more treats than tricks.

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

Larry


What Bird Am I?
Can you determine what type of bird this is? The answer will be in next week's post.

Last week's bird was a great blue heron.











Sunday, October 18, 2015

A Fall Feud

When the leaves turn golden and the birds begin wearing their new fall colors we know autumn has arrived.


Sometimes golden isn't good enough. For a brief moment, between the golden and the brown, this non-native maple turned a brilliant shade of red.

Some birds almost seem to imitate the leaves.

I suspect orb spiders are the same color all year round, however in the fall they and their golden color seem a bit more obvious. As the spiders prepare to lay their eggs their size and hunger must both be increasing

Last week, I came across Rod Crawford's spider site. Mr. Crawford is the Curator of Arachnids at the Burke Museum. His information is fascinating. Do you know how orb spiders consistently space the strands in their webs? They measure with their legs. Did you know that every night they destroy their webs and each morning they build a new one? Certainly the most entertaining part of Mr. Crawford's work is his myth busting. If you have a fear of spiders, or need a smile, you should read his responses under Spider Myths.

Flickers sometimes have some golden color on their backs and heads. However, what caught my eye this morning, was how the bubbles of sap in the tree bark and the spots on the flicker look so similar.

The stars of this week's post are the Bewick's wrens. When these little birds break into song the whole world listens. I suspect, ounce for ounce, they might be the loudest creatures on earth. The last song on All About Birds sounds the most similar to what I heard this week.

In spite of their vocal capabilities they usually work quietly in the shadows.

However, when they venture out they carry themselves with a sense of pride. Maybe it was a Bewick's wren that invented the concept of real estate and property ownership.

This week, I watched two of them carry on a lengthy discussion regarding the exact location of their mutual property line.

One bird clearly believed it owned this caucasian spruce.

The other thought it retained the deed to this crab-apple tree. There is only six or seven feet between the edges of two trees in the Arboretum.

When the spruce owner wandered too far away, his neighbor would sneak over and land in the lower branches of the spruce tree.

If this did not induce an immediate response the intruder would begin to sing. I presume it was something about possession being nine tenths of the law.

This would drive the spruce owner out of his wits. He would come blitzing down tree and chase his neighbor into the grassy no-man's-land between the trees.

At one point the bird in the crab-apple tree seemed to get a bit choked up. I am not sure if it was something he ate or something his neighbor said, but in any case he survived to sing again.

The process was repeated over and over with neither bird giving an inch. After twenty minutes I was beginning to think it would never end. Finally, something in a white-barked birch tree distracted the crab-apple owner. He flew away. I am sure the truce is only temporary. If I could identify them as individuals, I would call them Hatfield and McCoy.

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Thank you to all the reader's who responded this week with their personal crow stories. The response has been varied and wonderful. I will be transcribing and publishing the responses as time allows during the next week. Thanks again!

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Have a great day on Union Bay...where the feuding never ends!

Larry

What Bird Am I?

Can you determine what type of bird this is? The answer will be in next week's post.

Last week's bird was a double-crested cormorant.