I prefer the above scientific name to the Check List name, because I can not believe that the Aleutian sandpiper is a subspecies of the purple sandpiper. The Aleutian sandpiper was originally described by Robert Ridgway (1880) as a distinct species. Later it was treated, and still stands on our Check List, as a subspecies of the purple sandpiper, because it somewhat resembles it in its winter plumage. In Mr. Ridgway's (1919) latest work, he treats it as a subspecies of the Pribilof sandpiper, a closely related form, which had been previously described; he there describes it as "similar to A. p. ptilocnemis but decidedly smaller and much darker in color; the summer plumage with blackish and rusty or cinnamon-rufous predominating on back and scapulars, and all the colors much darker and more extended. Very similar in winter plumage to A. maritima, but summer plumage and young very different, both being conspicuously marked with rusty on back and scapulars, and the summer plumage with breast conspicuously blotched or clouded with dusky."
Among a series of 11 birds of this species, which we collected on Attu Island, at the extreme western end of the Aleutian Chain, on June 23, 1911, are two birds which closely resemble ptilocnemis in color, but in size are typical of couesi. At least one of them was a breeding bird, the parent of a brood of downy young, and doubtless both of them were summer resident birds. Dr. Ernst Hartert (1920) has described the resident bird of the Commander Islands as a distinct subspecies, under the name Erolia maritima quarta, of which he says: "In full summer plumage the feather-edgings are broader than in any other form and brighter, more rusty red, so that the rusty red seems to predominate on the whole of the upper parts." This description seems to fit our two birds from Attu Island very well; so that, if quarta is a recognizable form, as it seems to be, this subspecies should be added to our North American list. The birds could easily fly across from the Commander Islands to Attu Island and establish themselves there.
Spring.—The spring migration of this sandpiper is not extensive. Many birds have remained all winter on or near their breeding grounds in the Aleutian Islands; others have wintered along the coast as far south as Washington. D. E. Brown tells me that they remain on Destruction Island until May 1 and that they have been seen on Forrester Island as late as June 15. H. S. Swarth (1911) found them "very abundant" on Kuiu Island during his stay there from April 25 to May 6; he writes:
In company with the black turnstone and some other waders, they frequented the broad mud flats, which, at low tide, extend over hundreds of acres at this point. As the tide advanced their feeding grounds became more and more restricted, until, as the last available spot was covered, the whole flock departed, with roar of wings, to some jutting rocks at the mouth of the bay, there to remain, preening their plumage and resting, until the receding waters again exposed the mud banks. The flocks seen at this place comprised many hundred individuals, and it is curious that the species was observed absolutely nowhere else.
Herbert W. Brandt says in his notes from Hooper Bay:
The Aleutian sandpiper is a common transient visitor in the vicinity of Point Dall and is said by the natives to be a breeding bird in the mountain fastnesses of Cape Romanzoff. This species was first identified by us on May 18, but it may have arrived a few days earlier because up to that time we did not suspect its presence. It associated itself with the red-backed sandpiper, to which in the field it has a marked superficial resemblance and in consequence we may have overlooked it. These birds at that time travelled in bands of from 20 to 40 individuals and at low tide fed on the ice-bound sea beach that was then exposed, but when the high water came in and up to the wall of shore ice, thus covering their feeding grounds, they moved back along the open river margins and marshy pond borders. From May 23 to May 28 they were very common, when suddenly they departed, only to reappear in early July. The natives are very positive in their assertions that this island dweller breeds in the rugged mountains about Cape Romanzoff, but as we did not visit that area we could not authenticate their statements, nor did we learn anything of its nidification.
Lucien M. Turner (1886) writes:
The Aleutian sandpiper arrives at St. Michaels early in May of each year, and in considerable numbers, being generally, on their arrival, in the dark plumage, which is changed for the summer by the first of June on this locality. On their appearance they are strictly littoral-maritime, resorting to the larger bowlders and rocky shelves covered with seaweed, among which these birds industriously search for slugs and other marine worms. Usually several birds are together, rarely singly, and seldom over 8 or 10 in a flock.
Dr. Leonhard Stejneger (1885) says that, in the Commander Islands: