I have been observing a lot of intense headshaking in the last few days on many nests around the metro, which is a sign of gnats ( black flies). It is troubling, given the high failure rate we documented last year on our nests...39% of the nests failed. We cant attribute it all to the same cause, but clearly black flies played a significant part. Our early spring was quite dry so I was hoping we would not have to deal with a large hatch of black flies, but after all our recent rains , I am afraid we are seeing the tell tale signs that the ospreys are being bothered. And this is happening right at the time when our nests are beginning to hatch. As was the case last year, some areas are worse than others. Hoping that this generation of black flies dies off quickly. The black flies are seeking a blood meal and newly hatched chicks are SO vulnerable, no feathers, unable to stand up, or even shake the gnats off, they become weak from blood loss and die.
We are still finding new nests, and seeing lots of extra ospreys flying around at established nests. At some point, quite soon, it will be too late to lay eggs...since these young chicks would need to be ready to migrate by sept or early October. There just isnt enough time to successfully complete the breeding cycle. And yet, new nests are popping up! So as this population grows, will we see more pairs that do not breed? We call these birds “housekeepers” , when a pair remains together, builds a nest, defends a territory , but does not breed. Is this part of the mechanism for population growth to level off? This is why I keep studying them! Still so much to learn!
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