Monday, August 17, 2015

Golden-Plover, Tattlers and things

Here are my pictures of the  Pacific Golden-Plover found a few days ago along Marine Dr on the Columbia River near the Portland Airport.  It is a probable second-year bird (hatched 2014).  On my OBOL post I simply said I saw the plover.  I was not sure what I was looking at along the river.  Others had ID'ed it as a Pacific. I have not seen enough of these two plovers in the past few years to know all their ins-and-outs. After studying my photos, it does seem within range of a Pacific Golden-Plover. 

Based on the 2004 Johnson and Johnson paper (link below) :

Golden-Plover link

Pacific Golden-Plover:

2-3 primary tips past the tertials
distance primary tips past the tail  0-9 mm
primary projection past tail < 1/2 bill length
tertial length relative to tail length :  extend to distal third of tail, many end at tail

Other points in O'Brien, Crossley, and Karlson compared to American:

more front-heavy, more upright, with rounder body, larger head  and bill, longer legs, and heavier chest

American Golden-Plover

4-5 primary tips past the tertials
distance primary tips past the tail 12-22 mm
primary projection past tail > 1/2 bill length
tertial length relative to tail length :  variable from half to distal third of tail

I have been wanting to read Jaramillo's 2004 paper but could not find it on-line.

Understanding molt sure increases the pleasure of studying birds.

I have received some private emails about this bird. Not sure if I am at liberty to cite the folks who helped me, but thanks much. I have also read some online opinions on the subject of large plovers and their wings.  One needs to be careful with counting the primaries past the tertials.  In spring, birds might be replacing tertials but not primaries.  So more primaries would be exposed.  Seems tertials are replaced in a few of the plover's molts, while primaries are not.  So care must be used with this id mark. Also the outer primary (P10) could be growing in and thus hidden behind it's neighbor (P9). 

Everyone seems to agree that extremely long pimaries indicate American.

One thing I noticed about this bird are its very worn primaries.  (See below) What does that mean?  It was explained to me that American Golden-Plover  molt their primaries in their first winter, Pacific-Golden-Plover do not.  So this bird's very worn primaries indicate that it could be a bird that was hatched in 2014, it just entered its second-life year. This will be the first winter that it molts its primaries.  An American Golden-Plover would not have such old worn primaries.

 A good way to separate first-spring birds, worn primaries: Pacific, new primaries: American.

Another hint that it could be a second-year bird is the greater coverts.  This is where I get a bit lost.  I was told the bird appears to have some retained greater coverts and they are basic looking. Possible evidence  that this bird had a mixture of breeding and non-breeding appearing feathers in its first spring.  The area of the greater coverts is forward of the tertials on a folded wing. I assume we are talking about the two brown and white feathers seen below? 

I took this shot to show the drooping supercilium behind the eye.  Pale face with bold eye.  Supercilium is brightest above the eye.  All marks for Pacific Golden-Plover as mentioned in O'Brien, Crossley and Karlson.

First-summer Pacific Golden-Plover, as with many shorebirds, can show an aspect that appears to be a mix of basic and alternate plumage.  It was suggested that the extent of black on this bird might have been the most it achieved in its first summer.  You can see the extent of black on the belly in both photos below..

The drooping supercilium  creates a wider dark  nape than on American.

I was supposed to go on a Newport pelagic trip this weekend, it was cancelled due to high winds. It would have been too rough and windy to be out on the deck of a boat trying to watch birds.  I tried to get out on the Westport trip but the last few spots were filled just a few hours before I discovered the Newport trip was cancelled.  SO a big skunk on my ocean efforts.  Another trip to Clatsop county was my third option.

Banded Snowy Plover seen on 8/16/2015 about 6 miles north of the 10th St access at Gearhart.  It is a hatch-year bird from the North Spit of Coos Bay, Oregon. Sorry for fuzzy picture, I finally figured out my viewfinder was not adjusted correctly, but that was after I left the bird.

One of a group of Spotted Sandpiper along the rocky coast at Seaside Cove.

One of a number of Wandering Tattler seen.  On OBOL I said 8, I trimmed that down to 6 in eBird, I think two got back in front of me.

A Black-bellied Plover on the Clatsop beach to compare to the Pacific Golden-Plover above.

This gull confused me a bit, it is a young Western Gull.  Wings not long enough for a dark California.  It was small , so I was thinking California, but was mistaken.

The fire at Parking Lot C burned the woods that abut the shorebird flats.  They should have let it burn out all the thick vegetation that has covered the spit in my opinion.

Photo of the shorebird flats, not much here is there?

Upon closer inspection the area is covered in Western Sandpipers.

A Gray Whale was working the area just beyond the surf Sunday morning.

Note Gray Whales do not have a dorsal fin, they have a bump that is followed by a series of ridges.  Bump has yet to pop out of water here.  A good tip when viewing whales from afar.

On my Tattler hunt along the rocky shore at Seaside Cove this seal kept an eye on me. It followed me along the beach.

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