Look for 2 adults on the nest. The adult pair will show pair bonding behaviors such as vocalizations, aerial sky dances, and the male feeding the female fish. You may see the pair copulating, which typically begins 14 days before laying eggs.
Females will lay 1 - 4 eggs at a rate of one egg every 1 - 2 days. After laying, incubation starts. Look for adults taking turns sitting low in the nest incubating eggs. The incubation period can last 35 - 43 days.
Chicks hatch ~39 days after incubation begins. Look for adults bringing food to the nest and making "head bows" into the center. Chicks typically can't be seen until they are 2 - 3 weeks old, so feeding behavior is the only way to know chicks are there.
Around 4 weeks after hatching, look for the heads of chicks to show over the rim of the nest, particularly when adults bring food to the nest. Other times they lie flat and are harder to see. Count the number of chicks in the nest before they learn to fly
Chicks begin flying around 7 - 8 weeks old, and are still fed by the adults. Count the number of chicks who have successfully fledged the nest and are observed flying.
Chick Last Observed
4 - 10 weeks after fledging, chicks begin leaving the nest area to migrate south, once they have learned to fly and feed themselves. Record the date that the last chick left the nest.
Look for signs of nest failure like adult abandonment, adults no longer incubating eggs or feeding young.
I am pretty certain this nest lost one of the two chicks. One fledged; it visited the nest on the other side of the bridge. I noticed this very behavior last year, too. I last time I saw a fledgling in the nest was July 10.
I am as certain as I can be that this nest has lost a young osprey. Two young ospreys were present in this nest on June 4. I saw only one young osprey in this nest when I visited June 8, 12, and 14. It was too early for it to have fledged.
Visited this nest June 8, four days after my most recent visit. Only one chick was in the nest. Since I observed the first hatchling April 26, even if the missing chick is the first hatchling, this would mean if it was missing due to fledging, which I doubt, it would have fledged about six weeks after hatching, which would be early. I will visit this nest again tomorrow to see whether this nest still has two chicks.
I checked on this nest in the evening of April 23; none of the two remaining eggs had hatched. I checked this nest again in the morning of April 26. Saw a half shell, so one egg hatched over the weekend. The mother left the nest briefly so I was able to watch the second egg hatch today!
I noticed an osprey sitting inside the nest as if on an egg several days before I was actually able to verify there were eggs. These two are on the ball. The nest directly opposite them, which I also monitor, has no eggs as of today.
I am concerned that this nest lost a fledged young osprey. I say this, because I have not seen two ospreys in this nest for over two weeks. I have seen three ospreys between this nest and the nest on the northwest side of this bridge (that nest has two 'original' fledglings), but I have not seen two in this nest and two in the other nest at the same time. I cannot be certain, though, because I know young ospreys visit other nests (I have documented this with my own photographs), so perhaps it has been doing so while I've been observing the nests. However, I observe the nests at different times of the day: early morning, mid-day, and right before nightfall, and I still haven't seen four young ospreys between the two nests.
This nest had two chicks. I observed the older of the two on Friday, June 26, 2020, with nice controlled flights from nest edge to nest edge. I did not see it fly from the nest, however. When I revisited this nest Sunday morning (observed for 2.5 hours), Sunday evening (1 hour), and again today (2 hours), I did not see this young osprey anywhere.
Well, she wasn't still incubating...she was keeping her three chicks warm on those very cool May days. Now that it's warmed up, these chicks are out and about, sleeping a lot, messing with each other, and asking for a snack--typical siblings! They look to be about two weeks old and are absolutely wonderful.
Both chicks have fledged and seem to be awkwardly gaining skill. Their landings are still very unsure and they fly far below their parents, screaming and crying for food. After a few minutes in the air, they land in the nest and continue their demands for food. Definitely fun to watch!
Okay, now we have two nests in this one spot...one on the left side of the bridge and one on the right. The left has been incubating for nearly a month now. The nest on the right is now fully completed and two adults are sitting on or near it. No incubation occurring as yet.
Today she was sitting on eggs while the male stood on the side of the nest. She is low with only her head showing. There is a second nest down the river that also had a female sitting on eggs so, although it's unusually early, I don't think she is alone in her incubating status.