Identifying Fledglings

A pair of adult Black Oystercatchers with their fledgling gave me lots of opportunities for photos today, Monday, August 20, 2018, to compare adults with juveniles. Dave Morrison, a dory fisherman and birder, had reported a juvenile with adults on the North side of Haystack Rock on August 3. I hoped they would bring their fledgling to Cape Kiwanda, north flats, as they usually do and they cooperated.

I first saw them on an offshore rock but it was a long view.

 I could tell that one had a partly dark bill and no red around the eye... a fledgling!

 After they flew to a closer area, the eye/bill comparison between adult (top) and fledgling (bottom) was easier.

adult

fledgling

And when they flew to a light-colored area (center of photo), even easier.

  adult (top) and fledgling (bottom)

 The adult found shellfish in this crack and brought one out.

Then showed it to the youngster...

This is a good comparison of the adult vs. juvenile body color and leg color. I had never noticed that the youngsters have paler legs than the adults until Dave Morrison, the dory fisherman who found the chicks on Haystack Rock, told me that's what he looks for.

The juvenile figured out how to open it and get the goodies inside.

Here are all three. Junior found itself another shellfish in the crack.

Pale legs, no red eye, partly dark bill = juvenile

A 4th BLOY flew in, which caused instant uproar with the parents chasing it north and out of sight. Junior promptly sat down, as chicks always do when their parents let out alarm calls. That works well for gray chicks on gray rocks but is not so helpful with fledglings on light-colored rocks.

After a few minutes one of the parents flew back and landed near the chick.

 Here all three are back together with Junior still "in hiding". I don't know how long the adults protect their fledglings like this.