Tuesday, April 13, 2010

Croak Loudly and Carry a Big Stick

Watching a Great Blue Heron hunt for sticks and branches for his nest is, for birders, like watching the Wide World of Avian Sports: a show filled with the thrill of victory and the agony of defeat.

Herons are about as tall as a second grader and have a wing span of six feet. They employ acrobatics, yoga, and hormone-propelled ambition to snap branches off, which are then shuttled back to the nest for precision placement.

When approaching a potential branch, he crouches in a hunting posture as he does when hunting for food in water.


With his target in sight, he coils his neck back


and darts forward, serpent-like, to claim the branch with his indomitable beak.


Then the majestic struggle begins. He spreads his wings out to counterbalance the extension of his neck.

Then he begins to navigate back through the tree canopy, unwieldy branch in beak. This is where the agony of defeat can occur: when his path becomes too treacherous or obstructed, he will resort to a cumbersome, clumsy flight--sometimes crashing through branches--to the nest. All that to get one stick to its nest. That's a lot of hormones.

To see more photos: http://www.flickr.com/photos/claremclean/?saved=1

(This bird is one of a handful of pairs that has been building a mini-colony on the UW campus, south of Drumheller fountain. This is the third year I've seen them there. I counted four nests in one stand of trees and two in another; I can't verify if all nests are active.)


5 comments:

  1. Beautiful photographs. Great Blue Herons are my friends on the Kennebec River in Maine. It's hard to get close to them. But you have.

    ReplyDelete
  2. Not being a birder, I have no sense of the world of Avian Sports - as you say, "a show filled with the thrill of victory and the agony of defeat". However, your great commentary and excellent photographs capture the essence of this ritual of Nature; they got me vicariously involved in the thrill. Thank you for that. The image of the heron in the hunting stance reminded me instantly of countless old-school Chinese martial arts movies that I have shamelessly enjoyed over the years... :)

    ReplyDelete
  3. Great Blue Heron are very territorial about their fishing sites. On the Kennebec River in Augusta, Maine during the alewife run they each establish their own spots on the gravel bars and you can see how there's a dominance ritual going on as some try to spook another off what apparently, in GBH terms, is the honey spot for fishing. That's when they do that weird, rough croaking sound.

    ReplyDelete
  4. Before I forget, while Clare's GBH's are on the left coast, on the US east coast, Great Blue Heron are highly dependent on anadromous (sea-run) fish runs such as alewives and shad and blueback herring. Dams decimated our herring runs in the 19th and 20th centuries and only now are the runs starting to come back, in some rivers, and with their restoration, the great blue heron and other fish-eating birds (like osprey) are making an amazing recovery. In the 1980s it was rare to see a heron on the Kennebec in Maine, and now they are everywhere. The secret is getting the fish back, which in our case in Maine has been directly due to a program of strategic dam removal, focussing on lower river reaches.

    ReplyDelete