Part 53

In Wilson’s time this Hawk was quite numerous in the marshes of New Jersey, Pennsylvania, and Delaware, where it swept over the low grounds, sailing near the earth, in search of a kind of mouse very common in such situations, and was there very generally known as the Mouse Hawk. It is also said to be very serviceable in the Southern rice-fields in interrupting the devastations made by the swarms of Bobolinks. As it sails low and swiftly over the fields, it keeps the flocks in perpetual fluctuation, and greatly interrupts their depredations. Wilson states that one Marsh Hawk was considered by the planters equal to several negroes for alarming the Rice-birds. Audubon, however, controverts this statement, and quotes Dr. Bachman to the effect that no Marsh Hawks are seen in the rice-fields until after the Bobolinks are gone. Dr. Coues, on the other hand, gives this Hawk as resident throughout the year in South Carolina.

According to Audubon, the Marsh Hawk rarely pursues birds on the wing, nor does it often carry its prey to any distance before it alights and devours it. While engaged in feeding, it may be readily approached, surprised, and shot. When wounded, it endeavors to make off by long leaps; and when overtaken, it throws itself on the back and fights furiously. In winter its notes while on the wing are sharp, and are said to resemble the syllables pee-pee-pee. The love-notes are similar to those of the columbarius.

Mr. Audubon has found this Hawk nesting not only in lowlands near the sea-shore, but also in the barrens of Kentucky and on the cleared table-lands of the Alleghanies, and once in the high covered pine-barrens of Florida.

After having paired, the Marsh Hawks invariably keep together, and labor conjointly in the construction of the nest, in sitting upon the eggs, and in feeding the young. Their nests are variously constructed as to materials, usually chiefly of hay somewhat clumsily wrought together into the form of a nest, but never very nicely interwoven; occasionally, in more northern localities, they are lined with feathers, in some cases with pine-needles and small twigs.

Richardson states that all the nests of this Hawk observed by him were built on the ground by the side of small lakes, of moss, grass, feathers, and hair, and contained from three to five eggs, of a bluish-white color, and unspotted. The latter measured 1.75 inches in length, and were an inch across where widest. The position and manner of constructing the nest correspond with my own experience, but the size of the eggs does not. The nests have been invariably on the ground, near water, built of dry grass, and lined with softer materials.

Mr. Audubon gives a very minute account of a nest which he found on Galveston Island, Texas. It was about a hundred yards from a pond, on a ridge just raised above the marsh, and was made of dry grass; the internal diameter was eight, and the external twelve inches, with the depth of two and a half. No feathers were found. This absence of a warm lining in Texas really proves nothing. A warm lining may be required in latitude 65° north, and the same necessity not found in one of 29°. A nest observed in Concord, Mass., by Dr. H. R Storer, was on the edge of a pond, and was warmly lined with feathers and fine grasses. Many other instances might be named.

The eggs found in the Galveston nest were four in number, smooth, considerably rounded or broadly elliptical, bluish-white, 1.75 inches in length, and 1.25 in breadth. Another nest, found under a low bush on the Alleghanies, was constructed in a similar manner, but was more bulky; the bed being four inches above the earth, and the egg slightly sprinkled with small marks of pale reddish-brown.

The prevalent impression that the eggs of this Hawk are generally unspotted, so far as I am aware, is not correct. All that I have ever seen, except the eggs above referred to from Texas, and a few others, have been more or less marked with light-brown blotches. These markings are not always very distinct, but, as far as my present experience goes, they are to be found, if carefully sought. In 1856 I received from Dr. Dixon, of Damariscotta, a nest with six eggs of a Hawk of this species. The female had been shot as she flew from the nest. With a single exception, all the eggs were very distinctly blotched and spotted. In shape they were of a rather oblong-oval, rounded at both ends, the smaller end well defined. They varied in length from 2.00 to 1.87 inches, and in breadth from 1.44 to 1.38 inches. Their ground-color was a dirty bluish-white, which in one was nearly unspotted, the markings so faint as to be hardly perceptible, and only upon a close inspection. In all the others, spots and blotches of a light shade of purplish-brown occured, in a greater or less degree, over their entire surface. In two, the blotches were large and well marked; in the others, less strongly traced, but quite distinct.

The nest was found in a tract of low land, covered with clumps of sedge, on one of which it had been constructed. It is described as about the size of a peck basket, circular, and composed entirely of small dry sticks, “finished off or topped out with small bunches of pine boughs.” There was very little depth to the nest, or not enough to cover the eggs from view in taking a sight across it. “No feathers were found in or about it. It was simply made of small dry sticks, about six inches thick, with about one inch of pine boughs for finishing off the nest.” The eggs were found about the 20th of May. They contained young at least two weeks advanced, showing that the bird began to lay in the latter part of April, and to sit upon her eggs early in the following month.

It will be thus seen that the eggs of this Hawk vary greatly in size and shape, and in the presence or absence of marking, varying in length from 1.75 to 2.00 inches, and in breadth from 1.25 to 1.50, and in shape from an almost globular egg to an elongated oval. Some are wholly spotless, and others are very strongly and generally blotched with well-defined purplish-brown.

This Hawk was found breeding in the Humboldt Valley by Mr. C. S. M‘Carthy, on the Yellowstone by Mr. Hayden, at Fort Benton by Lieutenant Mullan, at Fort Resolution by Mr. Kennicott, at Fort Rae and at Fort Simpson by Mr. Ross, at La Pierre House by Lockhart, and on the Lower Anderson by Mr. MacFarlane.

GENUS NISUS, CUVIER.

Accipiter, BRISS. 1760. (Type, Falco nisus, LINN.) Nisus, CUV. 1799. (Same type.) Astur, LACÉP. 1801. (Type, Falco palumbarius, LINN.) Dædalion, SAVIG. 1809. (Same type.) Dædalium, AGASS. (Same type.) Sparvius, VIEILL. 1816. (Same type.) Jerax, LEACH, 1816. (Same type.) Aster, SWAINS. 1837. (Same type.) Micronisus, GRAY, 1840. (Type, Falco gabar, DAUD.) Phabotypus, GLOG. 1842. (Same type.) Hieraspiza, 1844, Jeraspiza, 1851, and Teraspiza, 1867, KAUP. (Type, Falco tinus, LATHAM.) Hieracospiza, AGAS. (Same type.) Nisastur, BLAS. 1844. (Same type.) Urospiza, 1845, Urospizia, 1848, and Uraspiza, 1867, KAUP. (Type, Sparvius cirrhocephalus, VIEILL.) Leucospiza, KAUP, 1851. (Type, Falco novæ-hollandiæ, GMEL.) Cooperastur, BONAP. 1854. (Type, Accipiter cooperi, BONAP.) Erythrospiza, KAUP, 1867. (Type, A. trinotatus TEMM.? not of BONAP. 1830!)

GEN. CHAR. Form slender, the tail long, the wings short and rounded, the feet slender, the head small, and bill rather weak. Bill nearly as high through the base as the length of the chord of the culmen, its upper outline greatly ascending basally; commissure with a prominent festoon. Superciliary shield very prominent. Nostril broadly ovate, obliquely horizontal. Tarsus longer than the middle toe, the frontal and posterior series of regular transverse scutellæ very distinct, and continuous, sometimes fused into a continuous plate (as in the Turdinæ!). Outer toe longer than the inner; claws strongly curved, very acute. Wing short, much rounded, very concave beneath; third to fifth quills longest; first usually shortest, never longer than the sixth; outer three to five with inner webs cut (usually sinuated). Tail long, nearly equal to wing, usually rounded, sometimes even, more rarely graduated (Astur macrourus) or emarginated (some species of subgenus Nisus).

Subgenera.

Less than one third of the upper portion of the tarsus feathered in front, the feathering widely separated behind; frontal transverse scutellæ of the tarsus and toes uninterrupted in the neighborhood of the digito-tarsal joint, but continuous from knees to claws. Tarsal scutellæ sometimes fused into a continuous plate …

Nisus.

More than one third (about one half) of the upper portion of the tarsus feathered in front, the feathering scarcely separated behind; frontal transverse scutellæ of the tarsus and toes interrupted in the region of the digito-tarsal joint, where replaced by irregular small scales. Tarsal scutellæ never fused …

Astur.

The species of this genus are exceedingly numerous, about fifty-seven being the number of nominal “species” recognized at the present date. Among so many species, there is, of course, a great range of variation in the details of form, so that many generic and subgeneric names have been proposed and adopted to cover the several groups of species which agree in certain peculiarities of external structure. That too many genera and subgenera have been recognized is my final conclusion, after critically examining and comparing forty of the fifty-seven species of Gray’s catalogue (Hand List of Birds, I, 1869, pp. 29–35). The variation of almost every character ranges between great extremes; but when all the species are compared, it is found that, taking each character separately, they do not all correspond, and cross and re-cross each other in the series in such a manner that it is almost impossible to arrange the species into well-defined groups. From this genus I exclude Lophospiza, Kaup (type, L. trivirgatus); Asturina, Vieill. (type, A. nitida); Rupornis, Kaup (type, R. magnirostris); Buteola, Dubus (= Buteo, type, B. brachyura, Vieill.); included by Gray under Astur, as subgenera, and Tachyspiza, Kaup (type, T. soloensis); and Scelospiza, Kaup (type, S. francesii); which are given by Gray as subgenera of Micronisus, Gray (type, Accipiter gabar), the species of the typical subgenus of which, as arranged in Gray’s Hand List, I refer to Nisus. All these excluded names I consider as representing distinct genera.

The species of this genus are noted for their very predatory disposition, exceeding the Falcons in their daring, and in the quickness of their assault upon their prey, which consists chiefly of small birds.

SUBGENUS NISUS, CUVIER.

Accipiter, BRISSON, 1760. Nisus, CUVIER, 1799. (Type, Falco nisus, LINN.; A. fringillarius (RAY), KAUP.) Jerax, LEACH, 1816. (Same type.) Cooperastur, BONAP. 1854. (Type, Accipiter cooperi, BONAP.) Hieraspiza, 1844, Jeraspiza, 1851, and Teraspiza, 1867, KAUP. (Type, Falco tinus, LATH.) Hieracospiza, AGASS. (Same type.) Urospiza, 1845, Urospizia, 1848, and Uraspiza, 1867, KAUP. (Type, Sparvius cirrhocephalus, VIEILL.) Erythrospiza, KAUP, 1867. (Type, A. trinotatus (TEMM.?)) Micronisus, GRAY, 1840. (Type, Falco gabar, DAUD.) Nisastur, BLAS. 1844. (Same type.)

Nisus fuscus.]

=26588=, ♀. ½ =26588=, ♀. ½

Nisus cooperi.]

The species of this subgenus are generally of small size and slender form; but with a graceful and apparently delicate structure they combine remarkable strength and unsurpassed daring. They differ from the species of Astur mainly in less robust organization. The species are very numerous, and most plentiful within the tropical regions. The Old World possesses about thirty, and America about fifteen, nominal species. Several South American species are intimately related to the two North American ones, and may prove to be only climatic races of the same species; thus, erythrocnemis, Gray (Hand List, p. 32, No. 305) may be the intertropical form of fuscus, and chilensis, Ph. and Landb. (Hand List, No. 314), that of cooperi. But the material at my command is too meagre to decide this.

Nisus cooperi.]