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.
Started watching nest around March 14. No activity at nest.
March 21--No activity at nest, but a single osprey briefly drifted by at treetop height without stopping, then disappeared behind nearby trees.
March 28--one osprey on and near nesting site. Nest has been started. Osprey protected the platform from another osprey flying nearby
April 4--definitely a pair. First osprey to arrive seems to be the male. Both spending time on and off platform. some nest building activity
April 11--female sitting on nest most of the time. Male was out of sight, but then settled on nest near female. Male picked up a fish from the platform, flew in circle around nest, then landed again. Definite mating behavior after that.
April 18--female appears to be roosting on eggs. Sitting low with only head upright. Got up briefly to do what appeared to be egg rolling. The nest is over water and observation positions are below the platform level, so knowing if there are any and how many eggs will have to wait until hatching begins. Male flew by once during observation to deliver a fish--but flew off again.
One general comment: the platform is quite removed from regular foot traffic in a very remote spot. As I approach the platform, while still completely out of sight of the nest, I hear the bird(s) calling-I guess as a warning. The tree cover is quite heavy, so I believe the male sits on shore in a tree where any movement on the ground can be detected.