I'm not sure that it needed clinching, but I needed more views to be certain
in my mind. The problem was, on Saturday I'd seen the Pacific diver and it was
perfect. Small size, dark flanks, grey cheeks and small fine bill. It was so
different to the accompanying black-throated divers that it looked more like a
grebe than a diver. I was completely happy that I was watching a Pacific
diver, though I didn't see the chin strap or the vent strap.
However, then I went back on Sunday and saw what I thought at first was the
same bird, but the jizz didn't seem right. Features that had looked so good on
Saturday now looked uncertain or even wrong, and it was especially missing the
grebe like appearance. Then it rolled onto it's side..... no vent strap. At
this point I should say that I was watching the bird at 750m distance, so
picking up on jizz is difficult as are small plumage details and things like
bill size. But if it was a Pacific diver I should have been able to see the
vent strap.
Then there was a further complication which clouded my judgement. Up until
this point everybody had told me that the Pacific diver was currently the only
winter plumage diver in this area, and as if to confirm this, all of the
black-throated divers I had seen so far were in summer plumage. I was still
convinced that I had seen the correct bird on Saturday, but Sundays bird
looked like a black-throated to me. Had I got it wrong on Saturday? Was I
wrong on Sunday? Or where there actually two birds? I needed more views or I
would forever doubt myself.
With a whale watching trip booked for this afternoon leaving me with a free
morning, it seemed like a good opportunity to head back to Big Sand and make
the most of the flat calm conditions to hopefully get better views of the
Pacific diver. Instead of wasting time at the burn mouth near the campsite at
Sands, which is simply too far away, I headed immediately along the rocky
shore to a headland about a 1.5km to the north west and scanned from
there.
It took me a while to find the flock of 17 black-throated divers because they
were close to the island well over 1.5km away, but soon they drifted my way.
Almost immediately I spotted a winter plumage diver with them and excitedly
took some video, but no matter how hard I tried, it still didn't seem right
and after watching for a while I could only conclude that it was an adult
winter black-throated. It just wasn't a Pacific diver.
|
Pacific diver. Note the rounded head shape, small bill, grey
cheeks & complete chin strap. Also the fuller hind neck giving the bird a distinctive jizz. |
This was crushing and I was at the point of giving up, totally depressed
because I felt this now left my Saturday sighting in tatters. I must have made a
mistake, I was no longer convinced that I had seen the Pacific diver at any
time, and frankly I was even beginning to doubt that there had ever been one
at Caolas beag. After all, hadn't I been told that there was only one winter
plumage diver here? I had one last scan over the sea.
 |
Pacific and black-throated divers. Pacific can be up to 20% smaller than black-throated, and you can really see the difference in this photo. |
Amazingly within a minute I picked up a second winter plumage diver and knew
instantly that it was the Pacific. It's whole jizz was so different. It was a
long way out, probably 1km, but it was with a summer plumage black-throated
and the difference was stark. This was no indecisive "is it or isn't it?"
moment, this was a slap-bang in the face "That's it!" moment. I did a little
dance on the spot, but thankfully there was nobody to see, just a few bemused
and slightly nervous sheep.