The Pintail (anas Acuta) Breeding at Latitude 82[degree] N on Ellesmere Island, Nwt, Canada

A specimen of the Black-throated Green Warbler from Alaska.--Recently, while examining warblers in the San Diego Natural History Museum, I found the skin (S.D.N.H.M. 25978) of an adult male Black-throated Green Warbler (Dendroica virens) that S. G. Jewett collected at Idaho Inlet, Chichagof Island, Alaska, 18 July 1941.This bird had been incorrectly identified as a Townsend's Warbler (D. townsendi) and reported as such (Jewett, Murrelet, 23: 67-75).This is apparently a new species for Alaska, and the westernmost occurrence for the species.--R.GuY Mc-CASKIE, 1640 Guy Street, San Diego, Cali]ornia.The Pintail (Anas acuta) breeding at latitude 82 ø N on Ellesmere Island, N.W.T., Canada.--ThePintail (Arias acuta) is the only true dabbling duck that occurs regularly in the North American arctic.Its breeding range extends north to the northern coast of Alaska, northern Mackenzie, southern Keewatin, and northern Quebec.It has been recorded in summer from Banks Island and southwestern Baffin Island, but the only probable breeding site in the arctic archipelago is Cambridge Bay, Victoria Island (Godfrey, Nat.Mus.Canada Bull. 203: 58, 1966).This note reports a pair of Pintails breeding near Hazen Camp, Ellesmere Island, at latitude 81 ø 49' N in 1966.We saw a pair of Pintails frequently between 11 and 19 June.The two birds were usually together.Their activities centered about an estimated five acres of small ponds and marsh near which the nest was probably situated.Incubation apparently began approximately 20 June.The male was not observed after 19 June; the female was seen on 20 June but not again until we saw her foraging on a pond on 10 July.On 13 July she was on a large pond, 1,000 feet from the presumed nest area, with nine young.One chick was obtained and is now at the University of Saskatchewan Biology Museum.It was one or two days old, weighed 32.6 g, and had some subcutaneous fat.Its stomach was full of insect fragments.The female and brood were observed the next day on another pond a mile from the area of the previous observation.No Pintails were seen from then until 23 July when a female, probably the same one, fed with a group of five female Oldsquaws (Clangula hyemalis).We have no evidence that any of the brood survived.The adult female was not seen again.The Hazen Camp area is typically high arctic in having less than five inches annual precipitation, most of which falls as snow in fall and winter.Many streams and ponds dry up in summer, hence marsh habitat is rare.The general ecology of the area is described by D. B. O. Savile (Arctic, 17: 237-258, 1964).Daily mean temperatures are usually above freezing for 60 to 70 days from mid-June to late August.Summer temperatures are not appreciably lower than in more southerly arctic areas.The mean temperature in July is 42.7øF (P.S. Corbet, De/ence Research Board o/ Canada, Ottawa, Directorate o/ Physical Research (Geophysics) Hazen 30, 1967).Pintails require 5 to 6 weeks to mature in the northern part of their range (J.B. Gollop, pers.comm.).An additional 3-week incubation period suggests that a minimum of 8 or 9 weeks would be necessary to complete the breeding cycle.The summer at Lake Hazen seems marginally short, but successful breeding cannot be precluded.This breeding attempt is more than 700 miles north of previous breeding records of the species.It suggests that where suitable habitat occurs in the archipelago, Pintails will attempt to breed and that they may occur as a sparse marginal breeding population far north of their presently known range.

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