The birds which belong to the Harrier genus are characterised by long and—slender tarsi, covered with feathers on the upper portion only, and also by a sort of collar formed of closely-planted feathers, which surrounds the neck and extends on each side to the ears. Marshy plains, and woods situated in the vicinity of rivers, are their most frequent resorts. They build their nests on the ground, or close to it, in the brushwood, and in this respect differ from most of the Falcon family. When searching for their prey they skim over the ground, and always seize it suddenly, as if by surprise: if the unfortunate is lucky enough to avoid the Harrier's onset it is safe from pursuit. In Europe the best-known species of this family are the Hen Harrier (Circus cyaneus) and the Moor Harrier (Circus æruginosus), [Fig. 299].
Fig. 299.—Moor Harrier (Circus æruginosus).
The former bird is about seventeen inches high; it inhabits all the countries of Europe, and feeds on serpents, rodents, and frogs. When it succeeds in making its way into pigeon-houses or poultry-yards it commits great havoc.
The Moor Harrier feeds principally on game, to which it is extremely destructive. Game preservers consequently are their bitterest enemies. Their flight is not swift except when pouncing on their prey, when it is possessed of great certainty and velocity.
The other species we will mention are the Frog-eating Harrier (Circus ranivorus), which is a native of South Africa, where it feeds principally on frogs and fish; the Pale-chested Harrier and Jardine's Harrier (C. Swainsonii and C. Jardinii); and the Ash-coloured Harrier (C. cinerescens), which is met with in the extreme south of America. The latter has great powers of flight, and is always in motion, never halting except to seize its prey; it is very wild, and can only be approached when feeding.
The Caracaras (Polyborus, Vieillot) are a race of birds which form a link between the Falcon and the Vulture families. They have, like the latter, the projecting crop, goggle eyes; head partly bare of feathers, toes long, especially the middle one, and the claws but slightly crooked. They show a decided taste for putrid carrion. They do not, however, feed exclusively on it, for when opportunity offers they will capture mammals, young birds, reptiles, mollusks, grasshoppers, and even worms. These birds are essentially pedestrians; the slight curvation of their claws renders this easy, and it is not an unfrequent thing to see them walk at a slow pace for considerable distances.
Their name is derived from the cry which they utter. They are peculiar to South America, in which they are found in every latitude, and at all altitudes. They present, however, differences according to the region which they inhabit. Each species fixes itself in a zone, which becomes its special place of habitation. Thus the Brazilian Caracara ([Fig. 300]) is met with everywhere, from the coldest districts to the hottest countries, but only at a slight altitude, and in company with the Chimango Caracara (Milvago chimango), whilst the summits of the Andes are inhabited by the Long-winged Caracara (M. megalopterus); and the Chimachima Caracara (M. chimachima) inhabits the burning plains between the tropics.
The Caracaras, especially the common species and the Chimango, are distinguished from the other Falconides by an excessive amount of sociability: everywhere they seek out the vicinity of man. But we should be labouring under a mistake if we supposed that affection had any share in this alliance; egotism and self-interest are the motives which impel them to act thus. It is to feed at his expense—to devour the fragments of his meals, kill his Domestic Fowls, or take possession of the pieces of meat which are hung in the sun to dry. This bird, however, is useful, for it most efficiently performs the duties of scavengers.
The Caracara will craftily follow the sportsman, and steal away game that is not quickly bagged. It also accompanies travellers across the vast pampas to prey on the carcasses of the worn-out beasts of burden. It will even attack horses and mules which are galled by the pack-saddle, fastening greedily on their wounds, and would actually devour them alive if the quadrupeds had not the sagacity to dislodge them by rolling on the ground. It will also take up its abode near flocks of sheep, and if it can evade the watchfulness of the shepherd, will destroy the newly-born lamb.