Imagine a day out on the lake, sitting in a boat and enjoying the sunshine and the beauty of the surrounding hills. Suddenly the calm is broken when a large ball of feathers drops from the sky at a high rate of speed and hits the water with a splash like an atomic bomb. Seconds later the feathery ball emerges, spreading 5-foot long wings and clutching a large fish in its sharp talons.
The aforementioned ball of feathers is actually an Osprey, one of the most ancient known birds of prey that still exists today. There are many things that make this species unique, starting with the fact that they are one of the most widely distributed birds in the world. They inhabit every continent on Earth except Antarctica, and they breed everywhere in their range except South America.
Another unique feature about an Osprey is that they are piscivores, meaning that they are primarily fish eaters. In fact, the diet of ospreys consists of 99% fish. They pretty much eat nothing else. That sounds like a pretty boring diet to me, but it could be one of the reasons for their success, and maybe even for their comeback from being highly endangered in the 1950s as a result of DDT use. The banning of DDT in many countries probably was the main source of their rebound, though.
After evolving to eat nothing but fish, Ospreys have become master anglers. Several different studies have shown that Ospreys can catch a fish 1 out of 4 tries, sometimes with success rates of up to 70%. The average time spent fishing before a catch was 12 minutes. In other words, they’re good at what they do, so they stick to it.
Ospreys are much less picky about where they nest, and will gladly nest on man-made structures such as telephone poles, channel markers, or platforms designed specifically for them. They will also commonly nest in trees next to bodies of water, which brings me to the very reason why I was sitting in a boat on a lake and enjoying the sunshine and beauty of the surrounding hills earlier this summer.
One of my favorite wildlife surveys that I got to participate in as an AmeriCorps volunteer was the Army Corps of Engineers’ Osprey survey at Green Peter Reservoir in Linn County, Oregon. The purpose of this survey was to locate a series of Osprey nests that are closely monitored by the Corps, and determine if they were active, inactive, or defunct. It really was that simple. As indicated above, the survey is conducted by boat.
The process for finding the nests was also pretty straightforward, but they were not always very easy to find. We had maps of the reservoir with us that contained a series of points, each corresponding to a nest site. Most of the nests at this particular site were in trees, rather than man made structures which made them much more difficult to find. When I look back on it, the whole thing was very similar to Geocaching.
The thing that stood out to me about this survey was the fact that while the process was so simple and relaxing, we were still gaining just as much useful knowledge as we did on some of our more complicated surveys. It goes to show that while the actions we take may not seem that great, the impacts that come as a result can still be very deep!