Friday, January 10, 2014

Metabolic machines with feathers

I've been reading The Immense Journey by anthropologist Loren Eiseley. At one point in the book, he talks about the evolutionary achievement of a high metabolic rate and body temperature regulation, supreme characteristics of warm-blooded birds and mammals. The advantage of high metabolism is the ability to escape extreme environmental temperatures while maintaining peak mental abilities ( as opposed to hibernation that leaves an animal vulnerable to attack).

The downside of the high metabolic rate is that it requires great quantities of energy intake to support it. And with this, birds are amazing metabolic machines. It seems a bird's life consists almost entirely of obtaining food for itself and sometimes for its chicks. That, and the fact that birds have feathers and fly, make them one of the most appealing animals to photograph.

The technique of capturing food varies among the waders, but I can distinguish them into two distinct groups. On one end you have the exciting quickness of the egret or heron, or the "strikers". These birds puncture the water with their sharp beaks with dramatic results. This happens so fast that the naked eye cannot distinguish the details of the event that begins and ends within a fraction of a second. Only with a fast camera that can shoot at least 5 frames per second can you see how the event plays out. Of course to capture any of that, you have to be ready with finger on focus button while aiming right between the eye and the beak (the lores) with a steady camera. You have to anticipate where the bird's head will end up in the frame and prepare to focus on that spot. Area focus that can be easily moved around is a beautiful thing in this regard.

 Despite my efforts to capture the moment, most of my successful shots are the end results of the bird's success, as seen here. This is fine because having the bird's prey in the image is dynamic and interesting to look at.


The other type of wader that I call the "forager" are the woodstork, roseate spoonbill and white ibis. I have very few good images of a woodstork and even fewer of them foraging. I also have very few good images of roseate spoonbills and frankly, if it were not for their colorful wings, I would probably ignore them as they are relatively boring foragers. There is very little pazazz in their technique; sorry roseate, I know you are a favorite among bird lovers. Now for flight shots, they can be the deal breaker in making a superb image. The white ibis is a different story and I also have endless opportunities to photograph them foraging. They tend to poke and jab at the water, and often bring their prey out of the water before swallowing it. This gives them a dynamic quality much lacking in the roseates.

And last, a tribute to the nesting parents that must feed their relentlessly hungry chicks. This blog is a celebration of the bird and its survival. May they live on this earth forever.

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