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  • Pam Narney

Living On Osprey Time

Inaction at the Nest April 22, 2021 Issue 7


Only 32 more days until the eggs hatch, approximately. This is waiting time for all of us Osprey watchers. There are many things we can witness if we slow down and observe Osprey behavior.


This morning Gracie left the nest and landed on a neighboring piling. George replaced Gracie in the nest, but he is smaller than she is and he is so far down in the nest that I barely saw him.


Where in the world is George?


I suspect that he had a disgruntled look on his face. I do not know how she signals him to come relieve her or even if she does. Does George just show up occasionally and give her a break?


The experts say that most of these changes are precipitated by the arrival and transfer of fish. This makes sense, however, what I notice this year is a different pattern. George and Gracie seem to be taking turns sitting on the eggs. George has been on the nest a lot more than in previous years. Why the change in brooding behavior?


On her piling Gracie attended to her feathers.


Removing all of those fish scales


Imagine sitting on a nest for hours on end. By the time the chicks are born, she will look like what my granddaughter calls a hot mess.

Working on her hot mess look


Today she has spent an hour on that piling scratching her chin with her talons, shaking her head, preening her feathers, and generally cleaning up. She was looking disheveled, bedraggled, and sported a new Mohawk hair do.


The Mohawk


Her appearance will only get worse as time goes by.


So far, none of her exertions improved her appearance, but this activity is necessary. She is removing fish scales and reapplying oil from the preen gland above her tail. This is her waterproofing.


Gracie lightens her load before takeoff.


The pre-poop position


If you see an Osprey close to you lean forward and bend over, move. Otherwise, you will be covered with bird droppings.


As Gracie returned to the nest, George literally flew out of there with a relieved look on his face (artistic license) before Gracie settled onto the eggs.


Success at the nest depends on George’s food delivery. If the male does not feed the female enough, how could he feed 3 or 4 other mouths.


The Cornell Lab of Ornithology found that Osprey catch a fish once every four attempts. The time spent searching, hovering, and finally diving can be up to twelve minutes on average. Those fish can be as heavy as 15% to 30 % of the Osprey’s weight. This is a severe energy deficit for the male Osprey.


Imagine the stress on George. All winter he has only had to feed himself. During nest building and incubation he has to feed himself and Gracie. Soon he will have to supply food for the entire family. Maybe six birds. It must be exhausting.


It is frustrating to wonder what the pair did in South America all winter (They spend their winters apart.), where in South America they were, and if they are the same two birds who were on our nest last year. Remember, we had the male one year who was just not feeding Gracie. He either matured by the next breeding season or was replaced. Hard to tell. Gracie has a unique feather pattern on one wing, so her identification seems probable.


I’d like to get my Osprey banded with tiny transmitters, so I could follow their movements. I came close one year when Brain Watts from the Center for Conservation Biology was looking for Osprey to band. Our nest is in the water and did not fit the requirements. I believe the banding occurred on land nests where the biologists could use ladders for easy access.


A Kinsale friend reported that her Osprey were just beginning to build their nest. She asked if this wasn’t too late and what would happen to the chicks. While it is true that the earlier the pair breeds, the earlier she lays eggs, and the earlier they hatch, the better their chance at survival. The research on later nest building and egg laying is scarce.


The Kinsale Osprey could be juvenile or immature Osprey who were mating for the first time. Juveniles lack experience and don’t always have things figured out. They build the nest late, the male doesn’t feed the female enough, and the nest fails. Maybe that is as it should be for their first time. Or the Osprey compensate by laying fewer eggs, fewer mouths to feed. That ups their chances for success. Perhaps these Osprey are ill or weakened for some reason. There is no way to tell why they got a late start or what their future holds.


While waiting for the eggs to hatch, take note of the Osprey’s fishing technique. It is exhilarating to see an Osprey dive into the water and come up with a fish. It’s not as easy as you would think to observe that dive in action.


Focus on their fishing method(s), and tell me what you notice. Is there only one way for an osprey to catch a fish, the dive, or can Osprey execute an eagle like snatch and grab with their talons while moving low and fast over the water?


Observe, and we will compare our findings.


pnarney@gmail.com