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.
We still check on this nest and, on a fairly regular basis, find at least one of the adults perched in the nest tree. Very little attention seems to be given to the nest itself, and it looks more dilapidated each time we visit. Interesting, though, that the adults seem to show some fidelity to each other and the site despite the failure of the nest.
This nest appears to have failed. Incubation has ceased. The adults, still in the area, are sporadic visitors to the nest. They have been observed delivering and rearranging nesting materials, but we have seen no activity that resembles incubating/roosting/feeding. We plan to continue watching this nest with the small hope that we're wrong about the failure.
Lots of interest in this nest. We've seen as many as seven osprey in agitated flight in the immediate vicinity of the site. Saw the first pair perched together on the nest tree on 3/10, but the "ownership" of the nest seemed unsettled for the bulk of the month. A stable pair looks to be around the nest since 3/24.