Photo © Jane Purslow

In Defense of the Nest

Chapter Coordinator Kathleen Dougherty (Oakland County Parks & Recreation, Waterford, Michigan) shared with us the harrowing story about what happens when you threaten a mother Osprey’s nest. A Great Blue Heron that tried to perch on an Osprey nest in Kensington Metropark was soundly rebuked by the resident Osprey. Almost all birds will defend their nest from predators; however, Ospreys must additionally defend their nest site from non-migratory species that nest earlier, like the Great Blue Heron, that could potentially take over their nest site before the Ospreys return in the spring.

We also know that sometimes the situation is reversed, and Ospreys can challenge herons on their nests in turn. Usually, it does not end fatally for either species. In this instance, the heron made a full recovery and went back to its own roost site. We can’t say for sure whether the human witnesses are fully recovered from their shock yet.