[EBB Sightings] Oiled bird survey, Alameda

Fellow East Bay Birders,

I walked the Bay Farm Island shore this morning, facing Alameda Island,
from the Doolittle Bridge west. Making an assessment isn't all that
straight forward. With Scoters and female Scaup (the latter especially
at a distance) the stains didn't show up. At least, not to my eyes. But
after focusing on male Scaup, my estimate is that 90% of these showed
oil staining on the sides. Most of these birds seemed functional,
though a few were more severely oiled and obviously distressed. By
'functional' I mean they seemed to be swimming normally and not acting
distressed. But heck, maybe they're burned out from two days of
preening.

On some of the male Scaup, the outer halves of the eggshell white side
feathers were stained, the feathers seemed 'drooped' or weighted,
exposing the unstained lower feather halves. The stain-line was
sometimes straight enough to give the impression of barring, almost
like a natural plumage trait. Threw me for a loop at first and I
wondered if I had young males in transition plumage. But no, they were
stained.

5 of 8 Horned Grebes were oiled , one of them grounded.

I saw a single Western Grebe where usually I see scores. Unstained.

Of the perhaps three hundred Scoters and Scaup, I saw just eleven that
were in obvious distress; All were well out in the water where only a
boat could get to them. With Scoters I looked for intense preening
activity. I can only guess that my 90% estimate pertains to the Scoters
as well. None of the 8 male Bufflehead showed evidence of oiling.

I will return soon to walk the island side.

     Rusty Scalf
     Berkeley