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.
One adult male is sat on the perch nest to the nesting platform. Possible adult head peeking out of nest, could be female laying down but difficult to tell from the angle. Lots of calling heard from area.
One individual (sex unknown) is sitting in the nest. This nest is too far out into the marsh to be certain whether or not this individual is a juvenile or an adult. It remains motionless and silent for the duration of the observation.
Female is present with one chick in the nest. One individual soars nearby, and there is no alarm coming from the female. This is suspected to be her mate. Second observation notes that the female and chick have not moved, however there is a male individual a little ways away sitting on the marsh grass. He does not eat or move for the duration of the observation
One individual of unknown sex feeding one visible chick. There are two individuals opposite of this nest in trees that appear make the nesting pair wary, as they sit up at attention when the pair starts calling.
Confirmed female sits in the nest. After about two minutes male returns with a fish. Female remains seated and eats with onlooking male glancing out into the marsh for short intervals. Both sit facing into the wind after a while. Male leaves. Female adjusts positions and could be feeding chicks.