Part 10

It is supposed that an old gander always leads the migration flocks. While this may not be the case, it is reasonable to assume that adult birds, with their experience and intelligence, should determine the movements of the flock. Canada Geese sometimes fly in a line, sometimes abreast, but the V-formation is characteristic.

The Greater Snow Goose (Chen hyperboreus nivalis), a white bird with black wing-tips, sometimes flies across Pennsylvania. It has been recorded once or twice in huge flocks. The White-fronted Goose (Aner albifrons gambelli), a gray goose with a white area at the base of the bill, black spots on the belly, and yellow feet, occurs rarely. The Brant (Branta bernicla glaucogastra), smallest of our geese and similar to the Canada Goose but with only a suggestion of a white band on the neck, occurs rarely. It is a maritime species, not often noted inland.

WHISTLING SWAN Cygnus columbianus (Ord)

Description.—Size very large; neck extremely long, and wing-spread sometimes as much as 6 to 7 feet; sexes similar. Adults: Pure white; bill and feet black, a small yellow spot at base of upper mandible just in front of eye; eyes brown. Young birds are pale brownish gray in color, usually darkest on the head and neck. As the immature plumage is replaced by the adult plumage, a vague mottling appears. Length: About 4½ feet.

Range in Pennsylvania.—A fairly regular migrant along the larger waterways; rare and irregular elsewhere; occasional in winter. It is usually seen in early spring from March 20 to April 15 and from October 15 to December 1.

A flock of swans flying in the sunlight is an inspiring spectacle. The birds are so large and their plumage so immaculate that they attract attention everywhere.

They sometimes migrate in immense flocks. In storms or on foggy nights they may become bewildered and descend to smaller streams, but, as a rule, they are found only along large open stretches of water.

At Harrisburg, swans sometimes spend the winter along the Susquehanna when the water is open.

The Trumpeter Swan (Olor buccinator), always a very rare bird in the eastern United States, and of late thought to be on the verge of extermination, is even larger than the Whistling Swan. The bill of this species is entirely black, lacking the yellow spot which is characteristic of the adult Whistling Swan and being of a different shape.

AMERICAN BITTERN Botaurus lentiginosus (Montagu)

Other Names.—Thunder-pump; Bum Cluck; Stake-Driver; Plum Pudd’n.

Description.—Sexes similar; larger than Crow. Upperparts brown, considerably mottled, streaked, and barred with black; a glossy black streak from corners of mouth down sides of neck; throat white; neck and breast marked with broad buffy brown streaks, which are mottled with brownish gray, in imitation of dead cat-tail leaves; belly buffy; feet greenish; bill greenish yellow at base, blackish at tip; eyes bright yellow. Length: 28 inches, with neck stretched out.

Range in Pennsylvania.—Fairly common migrant and summer resident, nesting only in marshy situations. It arrives in early April and leaves in late September or early October.

Nest.—A platform of cat-tail leaves and stalks, or other dead vegetation, usually placed in a remote section of some marsh, among rather high weeds. Eggs: 3 to 5, pale buffy brown.

The Bittern is a terrestrial heron and rarely alights in trees. It may be confused with the immature Black-crowned Night Heron, which, unlike the Bittern, often perches on a prominent branch or on a tree top.

To know the Bittern one must penetrate the swamp. From the cat-tails, a great brown bird arises, green feet awkwardly dangling. Rapidly the creature makes away, once it has started; perhaps it utters a startled squawk as it jumps from the grass.

In the spring, male Bitterns have a remarkable courtship ceremony which is accompanied by the queer sounds which have given the bird most of its common names. These names, most of which are very good renditions of the queer sounds the birds give, are: “Bum Cluck” or “Plum Pudd’n.” The familiar nicknames, “Stake-Driver” and “Thunder-Pump” also suggest the sounds. While they give these sounds, the male birds inflate their necks and fluff out their feathers, as they strut and bow, and snap their bills.

The sitting mother bird depends greatly upon her remarkably protective coloration. Taken unawares, the hunting Bittern will stand erect with bill pointing skyward, realizing that its dull colors, its streaked breast, and its sharp bill all resemble cat-tail leaves. The eyes of a Bittern are so arranged that the bird can point its bill straight up yet at the same time look directly at us as we approach. Its golden-yellow eyes have a serpentine appearance.

Young Bitterns, in their ragged natal down, are odd creatures. They clamber about their crude cradle, soon developing remarkable strength in toes and feet.

The Bittern and young Black-crowned Night Heron are our only large, brown herons; the Bittern has yellow eyes; the young Black-crown has dark brown eyes.

LEAST BITTERN Ixobrychus exilis exilis (Gmelin)

Description.—Size very small, body hardly as heavy as that of a Robin; proportions those of a heron, however, with long bill and feet and short tail. Male: Crown, which has a crest, back, and tail, glossy black; back of neck chestnut; lesser wing-coverts buffy; greater wing-coverts and secondaries chestnut, darker than neck; underparts buffy, somewhat streaked on neck with white and fine lines of brownish; a black patch at each side of breast; throat, line along sides of back and of breast, and under tail-coverts, whitish; feet yellowish green; bill yellowish, tipped with dusky; eyes yellow. Female and immature: Similar, but black of crown and back less glossy, coloration throughout less striking. Length: 13 inches.

Range in Pennsylvania.—Rather rare migrant and summer resident, save locally, when it nests in cat-tail swamps and similar situations. Its date of arrival is open to question since the birds are so silent and retiring as to pass for the most part unobserved. They probably come in mid-April and leave in late September.

Nest.—A platform of cat-tail stalks and similar materials built on the ground, or a few inches above the ground, or in weeds above the water, and surrounded by high weeds and grasses. Eggs: 3 to 6, pale blue.

The Least Bittern is one of our quietest, most retiring birds, and is therefore but little known. It may occur regularly in cat-tail swamps where it has never been seen, simply because no one ventures into its damp, shadowy home among the high, green blades.

It moves slowly, as a rule, and with marvelous control. As it has very strong feet, it can climb up the cat-tail leaves where it sometimes perches so as to survey its surroundings the better.

If startled, it flies up rapidly; but, like a Rail, it does not like to fly far because its long, rather awkward wings appear to tire quickly, and it drops back into its retreat, where it is usually difficult to find it again.

The parent bird has the strange habit of destroying, and perhaps eating, her eggs if they are disturbed. We found a nest containing two fresh eggs at Sandy Lake, Mercer County. Upon returning, a few hours later, I found but a few shells in the nest. I feel certain the parent bird, either the male or female, had destroyed the eggs.