July 28, 2003 Commentary:
David Shore reports that for the "week ending July 26, the chicks are spending time away from the nest but return for feedings. The adults will bring a fish and leave it for the young birds, which then compete for it. Usually one or the other will get the meal and finish it without the other getting any, but they both seem to get their share over the course of the day. All four birds spend the night out of the nest."

How do we know where birds go?

Audubon wanted to know if the same phoebe showed up each year in his yard. He is purported to have put a small wire around one leg, maybe the first recorded example of bird banding or as they say in Britain, ringing. By banding birds scientists can discover where birds go and how long they live.

A friend, Jack Swenson, discovered two records on the web that answer these two questions. (Jack was at sea studying pelagic birds when he heard of Dennis' passing. Having worked with Dennis as a naturalist at Lindblad Expeditions he sent a letter that was read at Dennis' celebration. His letter can be read as part of the Dennis' celebration that is available elsewhere on this website.) Jack's two reports are summarized below, each with the website address provided at the end of the summary.

The first report is about an adult bird from a nest site in Scotland that is confidential (the need for confidentiality is usually because there are people who steal the eggs for collections). This bird had visited Scotland, Agadir in Morocco, Stamnared in Sweden over the years but in 1999 was trapped in nets covering crops in Kent, England. Released it was later found on the shore of Lake Volta, Ghana where it had been electrocuted. What was remarkable was that this bird established a new longevity record of 25 years, the previous record of 16 years being eclipsed by nearly a decade.
http://www.bto.org/ringing/ringinfo/recoveries.htm (British Trust for Ornithology)

The second report was about an osprey that had been captured on Loch Awe, Strathclyde, Scotland in 1998 and was found two years later in West Africa in Gambia in the stomach of a crocodile. The following website will give further information on ospreys.
http://www.ospreys.org.uk/AWOP/Home.htm.

And so as the young continue to exercise and to battle for food away from the nest, we can begin to contemplate what their migration route might be and where they might end up. A few years ago, some of the ospreys from The Nature Conservancy's Mashomack Refuge were radio-tagged and tracked by satellite. Their course paralleled the British birds in that they headed south down their respective coasts to the Equatorial regions. For the North American birds, some end up in the Orinoco in Venezuela, others in the Amazon where they stay for 2 or 3 years before coming back to their natal nest sites.

Some previously posted questions are answered here.
Responses are by a number of our experts.

Question: If something were to happen to one parent, could the other parent safely get food and return to feed and keep the chicks warm.?

Response 1: This would depend on how old the chicks are at the time they are left with only one parent. I would say if they are in the downy phase, they would be too vulnerable to weather or predators to leave for the time it would take to find food. Once they develop their juvenile feathers and are standing/pecking at their food and each other, it would be safe to leave them long enough for one parent to get a fish and return to the nest. In some locations, a great horned owl, or other predator could take an unprotected young chick or weather conditions (too hot, too cold, rain, etc.) would create a dangerous situation for the chicks.

Response 2: A case recently in Florida where a baseball player threw a ball at an osprey nesting on a light pole and eventually damaged one so badly that it died. I think he was fined. What was interesting is that the other parent continued to feed and shortly, I don't know the length of time, another osprey began hanging around and helping with the chicks.

Question: Do ospreys fish in the ocean?

Response: Ospreys fish in the ocean. I used to see them flying over bunker (menhaden schools off the Surf Club in Quogue) schools. These schooling fish are easy to catch as they are surface feeders and the ospreys had no trouble catching a fish.

Question: How do you tell male from female?

Response: Usually you don't. Sexual dimorphism in ospreys is slight; yes females tend to be larger and broader through the wings, but unless you have a comparison this is of little value. Most females will have a fairly well developed brown patch on the upper breast (this seems to be more evident as the nesting season progresses), and most males will be clear white chested. Behavioral observations can help provide important clues to sex, e.g. males deliver most of the fish, females usually feed the young, and males are always on top during copulation. We call the brown speckled breast of the female a "necklace."

Question: How do the nests stay up on platforms in high winds especially during hurricanes?

Response: They don't. As the nest gets larger and wetter with rain and therefore heavier the tree, usually a dead tree, breaks. That is what happened a few years ago to the nest on the southwest side of the Carmans River intersection with the road that passes in front of the canoe rental place. It may also be why such a high percentage of nests now are on artificial structures which have more permanence than dead trees.

Visit our Ospreycam any time and this webpage again for an updated commentary for the week.