Delaware Owlets May, 2009

Delaware Owlets May, 2009Dick Phillips arrived at my home at 09:00 on May 12 to begin the fourth trip to monitor 18 American Kestrel nest boxes that hang from utility poles along a fifty-mile roadside route in Delaware County, Ohio. Before we set out, however, I grabbed my stepladder and we walked to a weathered, wooden Wood Duck box in my back yard. There, we attached U.S. Fish and Wildlife Service leg bands to four Eastern Screech Owls. The owlets were 18 days old and easy to handle. Two clicked their bills as they were picked up, and because of their young age, their young leg muscles were too weak to adequately deploy their sharp talons, so we did not need gloves. Furthermore, their mother’s absence made the banding event less anxious for the banders.

The owlets were plump and healthy, especially since I had fed the family three fresh House Sparrows the day before. So far, I have trapped 19 sparrows from my bluebird trails and recycled them into owlets. I don’t want to feed too many sparrows and cause the male screech to feel inadequate.

Delaware Kestrel Chicks, 2009After we fitted the owlets with new identification bracelets, we left for the countryside for several hours. At each of 18 nest boxes, we used a fiberglass ladder to gain access to the nest chambers. We counted 14 American Kestrel nests active with eggs or young, which is two more nests than counted on April 29. One additional nest box contains a “kestrel cup” fashioned from a starling nest. Both sparrow hawks were at their site today, a nest chamber that two weeks ago showed the remains of a half-eaten European Starling that revealed a gory story.

During monitoring, we removed starling eggs from three nests (6,7 and 7 eggs). We did not remove starling nest material from two nests since kestrels will rearrange grass nests to their own liking. As for the failed Troy Road nest, starling material was removed to better search it for information as to why the kestrels failed. So far, one eyewitness account of an encounter between a Peregrine Falcon and its smaller cousin over Troy Road offers the only evidence for a possible explanation as to what might have happened to this nest.

Two of the 18 kestrel boxes are on public land. Box No. 16 at Gallant Woods Preserve contains five nestling falcons that are around five or six days old. Their eyes are open and no feather quills have emerged. Box No. 17 hangs above the original Leonardsburg Road on the Delaware Wildlife Area. It contains a full clutch of five eggs.

Delaware Kestrel Adult, 2009Only one falcon family was old enough to band. Dick and I banded the season’s earliest family whose first egg appeared on March 24. The fifteen-day-old nestlings were old enough to be sexed (three females and two males.)  At 12 days, primary wing feathers have sprouted enough to show brown feathers on females and slate-gray on males. Toward the end of next week, four more families will be old enough to band. Once a family is banded, there is no longer a reason to monitor them, so the number of nest box visits diminishes weekly.

The two Kestrel photos here show females with nestlings. Note the eye spots on their napes and their beautiful coloration. Both nest chambers are thoroughly whitewashed with excrement from previous years’ use, images not normally published in popular bird magazines. As the families mature, the stench of ammonia builds. The birds appear to be oblivious to the fumes that might act as a disinfectant toward some microbes, and a deterrent to predators. The nestlings are always clean, however.

Enjoy those raptors!