Tuesday, 14 August 2012

Long-billed Dowitcher photo shoot

I've never yet been fortunate to come across a lone dowitcher in the Britain or Ireland. Admittedly I've seen a lot of them (over 15 in fact), occasionally in braces, since the first stonking adult that I was lucky to see on the Weaver Bend, Frodsham back when I was just a young lad in 1990. Add to this three on the Azores and throw in a couple of Short-billed Dowitchers at Rosehearty and Lady's Island Lake for good measure, and hell yeah, you'd think I was some sort of expert on them. Well no, nobody is to be honest and the more you look at adults (juveniles are slightly easier) the more you realise that things are not always that straightforward. And these guys have fried with my brains to be honest. Unless you get them to call of course. Which these birds did thankfully, or at least the birds that called were Long-billeds! All photographs taken at Shollenberger, Petaluma, California in some nice crisp evening light on 6th August 2012.
Long-billed Dowitcher possy Shollenberger, Petaluma, California 6th August 2012
In the US, habitat preference is a fair indicator according to the correspondence I had with Californian legend Rich Stallcup. Short-billed with a major preference for tidal, saltwater situations while the Long-billed are much more inclined towards freshwater, where these shots were taken. Obviously any vagrants in the UK won't be as habitat faithful... and you'll also see that bill length and moult timing are both variable to say the least.

Tail pattern isn't that much of a decent feature, which isn't how I envisaged it or what I wanted to hear. Nor really is wing projection beyond the tail. Basically Long-billed are pretty variable with either even bars or broader dark bars. But, then again, have a look at these images to see the variability in just this one flock. Have a read of this to get you thinking even more, and this one too that contradicts a lot from the previous link! It'll totally screw your head up, just like it has mine.

Also, primary and secondary feather moult takes place in Long-billeds at migration stop off sites while in all subspecies of Short-billed Dowitchers they moult their primaries predominantly on/near their wintering grounds (per O'Brien, Crossley and Karlson).

Any comments appreciated, as adult dowitchers are more baffling than I thought a few weeks ago.

1 comment:

  1. Had great views of both east coast subspecies of short-billed and long-billed at Jamaica bay, all feeding together. I could tell them apart then (just, but it's not exactly inspired confidence in me to nail the one that turns up at Corragaune. FWIW the americans were just resorting to flushing and listening