Trees: A Key to Understanding Birds

Once you learn the names of the trees around you, your understanding of birds will increase.  Your field notes will take on greater depth if you identify the trees where the birds are carrying out their activities.  You may find, for instance that Winter Wrens are understory birds, not canopy birds.  You might get Eureka moments such as these:  "Hmmm, Bald Eagles tend to perch and nest in Cottonwoods in this region."  "That's the third time I've seen Brown Creepers foraging for insects on on the main trunks of Douglas Firs."  "Snags around here show excavations by Northern Flickers and Pileated Woodpeckers."

     Of course, these are not 'laws' of fixed behavior.  They are behavioral tendencies that will help you understand the ecosystem that sustains the bird.

Adult Bald Eagles in a Cottonwood

Lummi Reservation, WA

Below: Black Cottonwood

Populus trichocarpa

Below: Adult Bald Eagle at Edison, WA

The age of trees is also a factor in bird behavior.  For instance, the Marbled Murrelet, a seabird, must nest atop old growth conifers, like the giant Douglas Fir shown below.  Spotted Owls also depend on 'old growth'.  This may lead you to question if changes in forest composition (by forestry, agriculture, and urbanization) will have an effect on these and other birds.  Which birds are adapting to urban 'forests'?  Which birds are failing to adapt?  Your observations may help in long-term studies and conservation decisions.

You probably cannot estimate the tree's age, but you can tell its diameter.  The bigger the diameter, the older the tree!  Forest botanists measure the tree at four and a half feet above the ground, in centimeters (DBH: diameter at breast height).  The old growth Douglas Fir, below, is nearly four meters in diameter at DBH!  Since Douglas Fir tree rings are from 2 to 5 centimeters wide on the stumps I have seen, that makes the tree at least 400 years old.  The lichen, Lobaria oregana, that I found near the tree, is another indicator of a mature or an old growth forest.     

Old Growth Douglas Fir
Pseudotsuga menziesii

Lettuce Lungwort
Lobaria oregana
An indicator of old growth trees

Recognizing the trees and shrubs in your habitat will allow you to see patterns in avian behavior.  You can relate this behavior to tree species with the five Ws: Who, What, Where, When, and Why.  Look where birds spend most of their 'tree-time':  the crown and upper canopy?  the lower branches and understory?  the forest floor?  In the open?  Do they prefer certain species for specific activities?  Do they avoid certain species of trees?  Does the maturity of the tree matter?

HERE ARE FIVE CONIFERS THAT SERVE AS BIRD HABITATS IN BELLINGHAM.

Above:  Douglas Cedar Cone and Needles

Above:  Red Cedar

Thuja plicata

Above:  Western Hemlock

Tsuga heterophylla

Above:  Grand Fir

Abies grandis

Cones are upright, like all true firs

Above:  Sitka Spruce

Picea sitchensis

 Learn the trees and the web of life will not just be an abstract concept to you.  For me, observing ecologically means:

- learning the habitats in this region.

- learning the plants (especially trees and shrubs) in those habitats.

- journaling species interactions, whether they be Boletus Mushrooms, Banana Slugs, Birch Trees, or Bushtits.  
-using the 5 Ws: Who, What, Where, When, and Why.


If you would like to read more about old growth trees, I highly recommend the National Geographic October 2009 article called "The Tallest Trees: Redwoods".  

Shorthand for Field Notes

Do you think bird watching is just identifying and checking birds off a list?  Start looking at birds' behaviors, interactions, and interdependence with the environment.  Start a field journal.  It will turn you into a naturalist.  A great book to help encourage you to become a naturalist is Crow Planet, by Lyanda Lynn Haupt.  The book is partly about corvids (Crows, Ravens, Jays, Magpies), but the theme running through it is that you can be a naturalist.  David Sedaris called this book, "A completely charming and informative book on the pleasures of keeping your eyes open."

"But the only bird I can recognize is a Crow!"

Crow at Port Townsend

If you want to be an amateur biologist or naturalist, then you've got to start observing and recording, no matter if the only bird you can recognize is a crow.  If that is so, then look at crows!  They're interesting.

Crows at a garbage dumpster in Alaska

Journaling to Remember

I suggest carrying a small notebook and mechanical pencil with you.  I carry a notebook that allows me to write on rain-resistant paper.  Have an expectation that you may see some wonderful episode of nature unfolding.  Be ready to write what you see, because our memories are far from perfect.

For example, in this picture, below, I took notes on a curious interaction.  This occurred in the raptor center in Sitka, Alaska, two years ago.  The raven behind the fence, in the cage, was doing the solicitation gesture (vibrating the wings) for the wild, larger raven outside the cage.  It was also trying to push the piece of meat through the wire screen to its wild, potential friend.  This was in the spring, at the height of mating season, which may explain the behavior.  If I hadn't written these notes in my handy notebook, I probably would have forgotten some of the details of the encounter, by now.  

Captive Common Raven (behind screen) attempting to feed a wild Common Raven (on near side of screen).  Corvids are sociable and intelligent.

Sketching to Remember

My field journals are full of sketches and cartoons that quickly remind me of the action I am seeing.  For me, at least this is a better mnemonic than writing.  Sibley, whose field guides on birds are exceptional, suggests that we make quick sketches on how different birds fly.  For example, if I wish to show that the raven, below, is soaring and not flapping its wings, I will write CORA (Common Raven) with an arrow and a direction indicator (like NE) and  a diagonal line, /, across the arrow to symbolize outstretched wings and soaring.  Later, I can add words in my field notes.

Above: Raven in flight

Invent a Shorthand

Things happen fast in nature... too fast for writing in sentences.  Having a shorthand helps.  For the Merlin Project, described in the October 15th blog, all my field notes are standardized to conform to the chief researcher's codes.  This is a Merlin observation in code.  Your notebooks don't need to look like this!

Below:

This says that at 5:31 AM a male Merlin 'flutter flew', while vocalizing ("Kee-Kee-Kee-Kee").  He flew to the a Douglas Fir (Pseudotsuga menzesii), which served as a prey-exchange tree.  His female mate met him and he delivered the prey to her.  Then, she flew to a Sitka Spruce (Picea sitchensis), acting as a pluming tree, where she pulled feathers from the prey.  The male, then flew silently and quickly to the Southeast, out of sight (OSS).

For my personal field journals, I've developed my own, more casual 'short hand'.  It is based on the 5 Ws of journalism:  Who/What/Where/When/Why?  Here's an example:

Above:

This tells me that eight American Crows (AMCR) mobbed a Red-tailed Hawk (RTHA) and drove it from a Red Cedar, about 200 meters to a Cottonwood, and from there, out of sight (OOS).  This happened at dusk, behind my house.  It probably happened because the Red-tail was perched in the flight path of the crows as they flew to their evening roost and because crows mob raptors that may pose a threat.  Notice, my field notes are based on the 5 Ws: Who is involved?; What's happening?; Where did it happen?; When did it happen?; Why might it have happened? ('Why?' leads to your best guess based on observation... an hypothesis.)

I suggest that you develop your own shorthand.  After a while, you will start to see patterns of behavior and get a deeper understanding and appreciation of your bioregion.  

   

If you show as much curiosity as a Common Raven or an American Crow and you regularly take notes in the notebook you always carry with you, nature will reward you with new insights.

Merlins and Reading Nature

Over the past two years, volunteering with the Merlin Falcon Foundation, I've had at least 50 people ask me about that 'Merlin' or 'falcon' or 'little hawk' that was hunting birds in their garden or near their bird feeders.  Most often, when people thought they were seeing a Merlin (falcon), they were actually seeing a juvenile Sharp-Shinned Hawk, or sometimes a juvenile Cooper's Hawk, trying to get an easy meal.  I recently painted the picture, above, to show the differences between the Coastal Forest Merlin (Falco columbarius suckleyi) and the Sharpies.

Merlins, by Audubon

Look first at the eyes.  The Merlin's eyes are a dark, chocolate brown, surrounded by a yellow orbital circle and a light brow.  The Sharp-Shinned Hawk's eyes are a pale yellow when young, becoming more orange and reddish as an adult.  Now look at the breast and belly.  Our resident Merlins are darkly streaked while the juvenile Sharpies are lightly streaked and the adults are reddish-barred.  Look now at the tail.  The Sharp-Shinned Hawks have longer tail feathers with easy to see black bars.

Merlins are beautiful birds - energetic, amazing hunters of passerines (small perching birds), and good parents to their young.  They are also stealthy.  Most people I have talked to have never seen Merlins, even if a family nested near them.  The dark brown or almost black hue of their feathers blends in with the dark greens of Sitka Spruce, Western Hemlock, firs, and cedars.  In the canopy, they are almost invisible.

You will likely hear a Merlin before you see it.  If they are calling to their mate or fledged young or chasing off a large predator like a Bald Eagle, you will hear a fierce sounding Kee-Kee-Kee-Kee.  Look up quick above the tree canopy and you may see the avian equivalent to a jet plane.

female Merlin waiting for the male to bring food

female eating food brought by male

female doing post-copulation preening 

male watching over nest sight from a safe distance

post-fledging juveniles waiting for parent prey delivery

I believe in non-invasive field studies, where the birds can carry out their migratory, mating, and breeding activities without interference.  That's why I got involved in the 25 year long field study being conducted by the Merlin Falcon Foundation.  Check out their website, if you want to learn more of their life activities or hear vocalizations or get involved yourself.

When I first moved to this bioregion seven years ago, the birds and the forest flora were as unintelligible to me as a partly learned foreign language.  I was familiar with chaparral and oak forest ecology, found in regions South.  With time and patience, you can learn the 'language' of your local ecosystem.  You can learn to read nature and you can share those insights with others.  In the next posting of this blog, I will give some hints on keeping a field journal and I'll highlight another regional bird species.