Thursday, March 1, 2012

The Mighty Osprey

       The ospreys, still endangered but not nearly as rare as they once were, are coming back. They are majestic fisher birds with wingspans just 10 inches shorter than the bald eagle and bodies not quite as bulky. They build massive nests from sticks that they return to each year and put on additions so that they might comfortably cushion a child if that child so desired.

There is a pair that have nested at Delnor-Wiggins State Park in Naples, FL for several years. Three years ago their nest, complete with fledglings, was blown apart in a violent storm. Such are the
ways of nature. Everyone hoped they would rebuild but they did not. the next year a new nest appeared at the top of a tree whose canopy might have been destroyed in a similar storm leaving the perfect, almost flat, platform in a wide open space that these marvelous raptors prefer. Ospreys are amazing in their ability to soar, spot and dive for
the fish they hunt.  Because they are not as adept at turns as other raptors, they need these wide open areas. You won't normally find their nests deep within the limbs of trees as you might a hawk's or an eagle's. And, because their most common enemies (after man and the automobile) are scavengers such as raccoons who might climb and raid their nests, they like to be up high.

For the few weeks I've walked this part of the park the ospreys have taken turns sitting on the eggs and hunting for fish--the only food they eat. Today, one of them was sitting high on the edge of the nest. Of course I did not have my camera with me. But it appears the eggs have hatched which means mama and papa will be busier than ever keeping the fledgelings fed.

Many ospreys are terrific travellers. During migration they can log up to 160,000 miles in a lifetime. One osprey strapped with a tracking transmitter traveled from Martha's Vineyards to French Guiana, South America, in less than two weeks!

As mighty as these birds appear, they are actually quite fragile. The DDT years nearly wiped them out. A conservation success story, the ospreys' numbers began to climb back as soon as the DDT ban was initiated. Now, unfortunately, because ospreys often pick up fishing line and soda-can straps as well as twigs to add to their nests, this beach trash has become a deadly hazard for fledglings that get caught up in them.

Like many raptors, osprey eggs do not hatch all at once but over a period of several days. That means the first born is much stronger than the last and, when food is scarce, have a much better chance of surviving.

When I think about all the other threats our natural world has been subjected to...our lust for an easier, faster, asphalt-laden and chemical-driven life...I wonder if we will learn in time which "improvements" might eradicate other species...and if we do, will we be as lucky as we were with the osprey to enjoy their rebound.

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