May 11, 2006
Osprey Housekeeping
Nest Update: In about a week we expect to see the start of hatching. We'll talk more about the hatching process in the next web log entry, but a sign that the hatching has started is if the mother osprey is looking at the eggs a lot. She will hear and feel the chick trying to break through the egg before it makes an appearance, so her body language should indicate that something is happening.
As we've shown on the cam page, the father osprey has been bringing in some major fish lately. He seems to be a good provider, and that is a very positive sign if we are going to have more than two chicks surviving in the nest.
On another fish-related topic: Russ Yeaton, who is one of our cam watchers, recently shared some photos he took at Spring Point, in South Portland, Maine. The photos offer a good look at how an osprey carries its prey headfirst (to reduce drag) and how it starts eating the fish at the head. This is a common trait among fish-eating raptors because the head is supposed to be an easier area to tear into first. Click on the thumbnails below, and much thanks to Russ for sharing his photos.
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Osprey Housekeeping
Over the last couple weeks, I've seen images from several other osprey cams on the Internet where nesting is going on much as it is at our nest. On a couple of the cams, I've seen funny looking material that the ospreys have brought to their home nests, and it reminded me of one aspect of osprey behavior that is pretty unique -- ospreys are junk collectors.
Whereas eagles seem to be rather conservative in choosing their nesting material, ospreys are flamboyant and creative -- and this quirkiness is well documented. For example, osprey experts, such as Alan Poole, have noted that ospreys exhibit a fondness for bringing all sorts of odd objects to their nests, such as toy boats, hula hoops, bicycle tires, and fishing nets. In the book Return of the Osprey, author David Gessner became fascinated with a Cape Cod osprey nest that had a Barbie doll in it -- although he later corrected himself and said it might have been a Spice Girl doll.
Earlier this week on a Washington state Osprey Cam you could see a nest with a large collection of colorful odds and ends, most of it looking like plastic or paper items. But the Connecticut Audubon Osprey Cam stole the show when one of the parents brought a bright blue teddy bear to the nest!
The oddest thing we've ever had at the Blackwater Osprey Cam platform is a bird's wing. Ospreys do not eat carrion (only fresh fish) and are considered relatively amiable toward other birds that aren't trying to steal their fish or attack their nests, so it's not likely the ospreys would kill another bird. Yet interestingly enough, bird expert Arthur Cleveland Bent has reported that ospreys have been known to bring the wings of ducks and gulls to their nests -- just the wings. In addition, he reported of hearing about osprey nests on Natividad Island in California that were made partly from Black-vented Shearwater wings (an ocean bird).
Seeing the quirkiness of osprey housekeeping is part of what adds to our pleasure in watching these fish hawks, but it does have a downside. Fishing line is a frequent item in osprey nests, as are hooks, and six-pack plastic rings. And such items have been known to kill both adults and chicks, as the material gets wrapped around the birds' bodies and legs.
Biologists have found during annual osprey surveys in the greater Chesapeake Bay area, that at least 5-10% of osprey nests contained fishing line. In addition, a 2003 survey on the local Patuxent River revealed that more than half the osprey nests contained fishing line, as well as other man-made materials. As a result, biologists found ospreys with entangled legs, beaks and wings. On some occasions, the material even led to the starvation or strangulation of the young.
Fortunately, the U.S. Fish and Wildlife Service is pursuing a public education program to educate anglers, and those who live near the water, about the need to retrieve broken lines, lures, and hooks, as well as to cut open the circles on plastic six-pack rings before throwing them in the trash.
The U.S. Fish and Wildlife Service has published this Fishing Line Can Kill PDF flyer (640KB) that alerts citizens about the need to properly dispose of fishing material that might one day endanger an osprey family. So help out the ospreys by passing along this advice to any family and friends who spend time around bays, rivers, marshes, and lakes, which are prime osprey habitat.
Until next time,
Lisa - webmaster
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