At Barrier Lake, on July 4, 1951, two adults were feeding together in a bare lane which had been made and maintained by caribou. At Topagaruk on July 7, 1951, these plovers made up less than one per cent of the avian population. They were frequently on polygons having raised centers. Non-nesting or non-breeding birds were on bare wind-blown knolls adjacent to the river. On these knolls they fed with semipalmated sandpipers, pectoral sandpipers, and ruddy turnstones. On July 9, we visited polygons having raised centers and young called continually but we could not locate them. The call resembles that of the long-billed curlew but is more plaintive. Ordinarily these plovers kept beyond the range of our collecting gun but when one of the pair was killed the other, especially the male, remained near the dead bird until the collector approached to within 20 feet. Of a pair shot on this date the male weighed 207 grams and had testes 7 mm long; the female weighed 232 grams and the largest ovum was 3 mm in diameter. The species was recorded at Topagaruk from July 4 to 10, 1951, inclusive.
At the west edge of Smith Bay on July 29, 1951, while flying from Point Barrow to Teshekpuk Lake, we observed one group of approximately 40 black-bellied plovers flying along the edge of the lake. At Gavia Lake on August 21, 1952, two young were just able to fly but preferred to run on the ground.
Arenaria interpres interpres (Linnaeus): Ruddy turnstone.—Specimens, 5: [Topagaruk] River, 155°48', 70°34', 10 ft., No. 30599-30603 including 4 ad. males and 1 ad. female, July 6, 8, 9, 1951.
Four males shot at Topagaruk July 6-9, 1951, weighed 105(96-116) grams. The testes were 2.8(2.5-3.0) mm long. A female from the above locality, shot on July 6, weighed 125 grams. These birds constituted less than one per cent of the avian population at Topagaruk and were more frequently on polygons with high centers and on high windswept knolls than elsewhere and were in company with black-bellied plovers, pectoral sandpipers and semipalmated sandpipers. One bird was observed on July 3, 1951, at ¼ mile southeast of the Arctic Research Laboratory at Point Barrow.
Capella gallinago delicata (Ord): Common snipe.—At Umiat (June 25, 1952) at 11:00 P.M. a female was sitting and calling from the top of a leafless alder tree some 210 feet from any favorable nesting grounds. A male was performing a nuptial flight overhead. Three other birds in the air were heard.
On July 13, 1952, at Porcupine Lake, we flushed a female from a damp meadow of grasses and sedges at the west end of the lake. She pretended to have a crippled wing. Seventy-five feet from this bird an abandoned nest and fragments of egg shells rested on top of a mound six inches from water and 10 feet from the west end of the lake. Two dwarf willows on top of the mound partly concealed the nest. Two days later (July 15), juveniles were caught in a line of traps set in this marsh. Four tree sparrows, one savannah sparrow and three species of small mammals also were taken from this marsh. At this time of year (July 15) all the terrain was free of snow and ice except that two patches of snow, one 8 × 12 feet and another 6 × 6 feet remained on the protected south shore of the lake and a few ice slivers remained in the deep crevasses on some mounds in the marsh. One bird was seen on August 13, 1952, in wet low polygons between Lake Schrader and Lake Peters.
Actitis macularia (Linnaeus): Spotted sandpiper.—At the south end of Lake Peters on August 15, 1952, after snow covered the valley, a juvenal spotted sandpiper remained along the shore line nearer camp than it had been for four previous days.
Heteroscelus incanum (Gmelin): Wandering tattler.—On each of the days July 3-11, 1952, a wandering tattler was flushed from dense high willows along an 8-foot-deep creek channel that carried water from the west end of Wahoo Lake into the East Fork of the Ivashak River. The bird was at home in the willows and had considerable dexterity in perching on limbs. Although the bird favored one section of the creek, an exhaustive search for young, eggs or nest was fruitless. A loud call was given by this bird when disturbed.
Erolia melanotos (Vieillot): Pectoral sandpiper.—Specimens, 52: Barrier Lake, NE Teshekpuk Lake, 153°05'40", 70°39'40", 8 ft., 33, Nos. 30616-30636, 30638-30648, 30754 including 5 ad. males, 12 juv. males, 1 ad. female and 15 juv. females, July 30, Aug. 1-3, 1951; Topagaruk, 155°48', 70°34', 7, Nos. 30649-30655, including 3 ad. males and 4 ad. females, July 6, 8, 9, 1951; Kaolak River, 159°47'40", 70°11'15", 30 ft., 6, Nos. 30610-30615 of ad. females, July 12, 14, 15, 18, 1951; Kaolak, 160°14'51", 69°56'00", 178 ft., 6, Nos. 30604-30609 including 1 juv. male and 5 ad. females, July 20-23, 1951.
The earliest record of young (135 mm in length and 26 grams in weight) was at Kaolak River on July 14, 1951. On July 9, 1952, at Topagaruk the oviduct of an adult female, 86 grams in weight, contained an egg in a shell 200 mm in diameter. Her second largest ovum was 10 mm. Breeding males on this date had testes averaging 11 mm in length. The average length of testis of 15 juveniles shot on August 3, 1951, at Teshekpuk Lake was 1.9 (1.5-2.0) mm. The average weight of these juveniles was 60(50-81) grams. A comparison of male and female juveniles shows no significant differences. Nevertheless, adult males in both the breeding and post-breeding seasons are longer bodied and heavier than adult females.