Weird Wader on the Wirral
A call from Allan Conlin on the Wirral told of an amazing dicovery, a Semi palmated Sandpiper on the beach at Hoylake, a very rare bird in the UK!
Steve Williams got some fairly distant picures of the bird which he quickly sent through to us.
On opening the files we were struck by the wader in the images, could it be a Western Sandpiper? Excited phone calls were exchanged with Allan and Steve and we began to suspect that the bird could indeed be a juvenile Western Sandpiper, an even rarer bird!
Here is Steve's picture that first set the alarm bells ringing. Luckily the bird remained in the area and a very interesting debate ensued with about a 50-50 split pro Semi palmated v Western Sandpiper began.
We called for help from our USA contacts and again we had a pretty even split Semi p v Western! Not an easy bird!
After more debate we heard from one of the USA's top birders that he considerd the bird a juvenile Western Sandpiper! Is this the end of the debate? We doubt it very much!
A great bird and good to have these debates in the birding world!
Here is what Cameron Cox from the USA had to say, very interesting stuff..
Since posting about the controversial North American sandpiper that was found in Scotland, things have taken an interesting twist. A second controversial Western/Semipalmated Sandpiper was found in England and has generated some debate. Below are my thoughts on the second bird found at Hoylake, Wirrel. After some review, I’ve decided to stay on the side lines on the debate of the first bird I posted, at least until a few more photos surface!
A bit of background: Semipalmated Sandpipers have bills that vary in length along an east-west cline. The longest-billed birds are found in the extreme eastern portion of the breeding range and migrate down the Atlantic coast of North America, whereas the shortest-billed Semipalmated Sandpipers are found in the western part of the breeding range and migrate down the Pacific Coast.
A friend asked me what I thought of the Hoylake bird and this is an abridged version of my reply:
The bill of the Hoylake bird falls within the amount of variation shown by shown by Atlantic Coast Semipalmated Sandpipers. For this reason, I will disregard the length of the bill and shape of the bill tip as a means to separate Western from Semipalmated in this particular case. However, the Hoylake bird does show a pretty thick base to the bill, a feature I would consider pro-Western Sandpiper. Overall I think the Hoylake bird is a Western Sandpiper.
My impression, based on the posture and of the bird and how it holds its feather, is that it is not 100% healthy. The extremely thick-necked appearance, slightly dome-shaped back and extremely rounded belly are not typical for either Semipalmated or Western (though it is slightly more similar to the typical structure of a Semipalmated Sandpiper), but reminds me of the structure of some of juvenile Semipalmated Sandpipers that linger well into November in along the Atlantic Coast of the US. These birds are presumably sick and often have a similar posture to the Hoylake bird. Likewise many of the Dunlin and Red Knot that oversummer along the Atlantic Coast instead of making it to the breeding grounds have the same overly fluffed up appearance. The birds that show this posture most extremely often also have visible tumors and are very clearly unhealthy. If you assume that the bird is at least slightly ill, that makes it difficult to rely on body structure or molt timing as identification traits. (Most juvenile Western Sandpipers begin to molt very early in the fall while juvenile Semipalmated Sandpipers delay their molt until they reach South America)
My opinion that the Hoylake peep is a Western is based on several somewhat flimsy characteristics as many of primary traits I usually use to identify these peep are not useful in this situation. The trait that swayed me the most is the impression of size given in the photo of the bird standing with a Sanderling and another photo where it is in the middle of a group of Common Ringed Plovers. The size compared to those other birds seems more consistent with Western as though it is clearly smaller, it is not totally dwarfed by them as would be expected if it were a Semipalmated Sandpiper.
American Sandpiper see pics on Hilbre Island blog pic 5
The fifth photo in particular looks dead on for Western as not does the size look right, the bill looks particular long and Western-like , the stance seems very erect and alert, a small point in favor of Western, and the distribution of weight seems more typical of Western though the bird’s overall structure still seems off.
Leg color is another characteristic that I consider pro-Western as the legs look jet black in the photos. The majority of juvenile Semipalmated Sandpipers in the fall have dark gray or dusky greenish legs and juvenile Semipamlateds seen in November typically still do not glossy black legs like the Hoylake bird.
Another trait is primary projection (the distance the primaries project beyond the feathers that cover them, the tertials, on the folded wing).
Typically this is of no use on when differentiating between adult Semipalmated and Western Sandpipers. However, juvenile Semipalmated Sandpipers show primary projection that, while variable, is usually significantly longer than that shown by adult Semipalmated Sandpipers, juvenile Western Sandpipers, or the Hoylake bird.
The Hoylake peep has clearly faded over the course of the fall, altering its appearance from what it looked like as a fresh juvenile. It lacks buffy tones or cinnamon edges to the wing coverts or tertials, but it still has noticeable amounts of rufous edging in the scapulars. I believe that a juvenile Semipalmated Sandpiper that showed as much color as the Hoylake bird does in the scapulars would also show a ginger wash across the back and show a hint of peach color in the crown. While I would not bet my life on it, the Hoylake peep seems more consistent with a Western than a Semipalmated.