17 April 2013

KEYING OUT THE MYSTERY


A few days ago, one of my former biology students sent me a Facebook message.  She had seen a bird with distinct markings, and sought out my help in identifying it.  I was gratified that her confidence in me has remained intact after twenty years, but I was also a bit hesitant.  You see, even though I've been an avid birder since my early 20s, and took a university ornithology class as part of my degree in Ecology & Evolutionary Biology, and have sought out local adult evening classes (which feature field trips guided by local experts) each time I've moved around the country ... nevertheless it has been at least ten years since I've done any serious birding.

Back in the day, I was pretty good at mentally sorting through a bird's field markings, songs, and behavior, and arriving at a tentative I.D. that was either spot-on or in the ballpark.  I would follow that initial impression by flipping through my reliable old Robbins field guide to the birds of North America ~ the species are arranged taxonomically, and with practice one can confidently flip to the correct page without reference to the index.  Less practice, less confidence.

My student's initial visual clues rang conflicting bells ~ a blue bird (but not a jay), with wing bars of red and yellow.  She lives in Pennsylvania, so there are several blue possibilities, but the wing bars are diagnostic of a Red-winged Blackbird (see above), which is, well, black.

I followed up with questions about her bird's size, beak shape and size, flight pattern, where she'd seen it land, and asked if she was certain the body color was one solid color, or whether there might have been different colors on the belly, chest, head, wings, or tail.  On a hunch, I sent Wikipedia's link to the Red-Winged Blackbird, and suggested that in certain light, its black feathers might iridesce to the illusion of a blue shade.

She shot back, "That's it!  You're the greatest!"  I was beaming.

My instincts were accurate, at least on such a common species. I'm far from a world-class birder ~ in that community, one is considered committed after having identified 700 species or more.  Those dedicated souls can usually afford trips to exotic places around the world.  My own life list totals a mere 350 species, including U.S. sightings in the Southwest, Southeast, Northeast, Northwest, and Alaska.  If I were to move back to any of those regions, many birds would be intact in my memory, but others would require verification in a field guide.  The price of an itinerant life, I suppose.

So now I'm leafing leisurely through my Robbins, which is heavily annotated with the dates and places of first sightings ~ getting re-acquainted with old friends.  Birding is a wonderful pastime ~ it gets you outdoors (ideally with other birders), it attunes you to habitats and weather and  the rhythms of the natural world.  The only requirements are a good field guide, a good pair of binoculars, and a willingness to be enthralled by beauty you hadn't expected.

The larger bookstores stock an array of excellent field guides with slightly different formats ~ guides by Sibley, Audubon, Peterson, National Geographic, et al.  Some publish range maps next to the species illustration and description, while other group range maps at the back of the book.  Some cover the species of half or all of a continent, others cover more limited regions.  I prefer whole-continent guides, so that I'm prepared when I travel.  Larger hardcover guides are fine for home, but look for a smaller, lighter softcover edition to carry in the field.  And don't forget a pen for keeping notes on your sightings.

A word about binoculars ~ you get what you pay for.  An investment in newer models by Nikon, Minolta, Pentax, Swarovski, Leica, or Zeiss with their state-of-the-art optics coatings is money well spent.  You'll find that binoculars are classified by a pair of numbers, e.g. 7x35.  The first number indicates the degree of magnification, while the second number is the diameter of the objective lens.  More magnification allows you to see the bird up close and in detail, but the narrower field of view may make spotting the bird more difficult.  A larger objective lens means more light-gathering power for greater clarity, but also implies a heavier instrument which may be hard to hold steady for long periods.

7x35 is a good entry level combination.  As you gain experience, you may wish to graduate to 8x40, or 10x50.  Useful tip ~ notice that in each pair, dividing the first number into the second number yields 5.  This relationship provides the best combination of magnification and light gathering ability.  You can find binoculars with greater magnification but a smaller objective lens to save on size and weight (for example, 8x20), but their performance is limited at best.  I have 7x35 and 10x50 binoculars, and would like to add a pair of 8x40s.

There are several online birding resources.  Among the best is the Cornell Lab of Ornithology's All About Birds website.  Browse the Bird Guide, Bird Cams, Birding Basics, and Living Bird tabs.  And have fun!

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