STERCORARIUS PARASITICUS. 
Arctic Skua. 
Lams parasiticus, Linn. Syst. Nat., ed. 12, tom. i. p. 226. 
Cattaractes parasita, Pall. Zoogr. Ross.-Asiat, tom. ii. p. 310. 
Lestris parasiticus, III. Prod. Syst. Mamm. et Av., p. 273. 
Stercorarius parasiticus. Gray and Mitch. Gen. of Birds, vol. iii. p. 653, Stercorarius, sp. 1. 
Lestris Richardsonii, Swains. Faun. Bor.-Amer., vol. ii. p. 433. 
Stercorarius richardsonii. Cones, Proc. Acad. Sci. Philad. 1863, pp. 121, 135. 
Lestris thuliaca, Preyer, Reise nach Island, p. 418. 
Richardson’ s Shua of British Ornithologists. 
No species of the genus is subject to greater changes of plumage than the present bird, and none exhibits 
a greater diversity in its colouring. The uniformly-coloured figure in the ‘Fauna Boreali-Americana ’ 
represents the bird in a somewhat abnormal dress ; for, although dark varieties occasionally occur among 
the specimens shot in the British .Islands, few are so uniform in their colouring. Swainson, not being 
aware of the variations to which the bird is subject, regarded the specimens under his notice as pertaining 
to a distinct species, and under this impression named them Lestris Ilichardsonii , in honour of Dr. 
Richardson ; but, as we now know he was in error in so doing, we are compelled by the law of priority to 
deprive the bird of the honour of bearing the name of that distinguished traveller and scientific naturalist. 
Although the seas of the northern hemisphere are inhabited by every species of this form, I have but 
little doubt of the present bird being the one most generally distributed, the regions of the Arctic circle 
in both the Old and the New World being tenanted by it. From these parts of the northern hemisphere 
its range extends over Europe and America, the British islands being perhaps the most southern country in 
which it breeds. It is abundant in Baffin’s Bay, Greenland, Iceland, and Norway, and a few years ago 
was scarcely less numerous in the Shetland, the Orkney, and Faroe Islands ; in the former they annually 
bred, but they are now far less numerous than formerly. During tempestuous weather and seasons of 
extreme cold, it proceeds to the southward ; and the young, wandering further than the adults, occasionally 
resort to the coasts of Portugal, Spain, and the Mediterranean. Still it is strictly a bird of the north, the 
greater number remaining in those countries during the months of summer, ever chasing the Gull and the 
Sea-Swallow, and tyrannizing over all the other birds they can master. 
“ In autumn,” says Macgillivray, “ when the fry of the coal-fish swarm along the shores, and shoals of the 
sand-eel sport in the waters, vast numbers of Gulls, Sea-Mews, and Terns frequent the sandy coast. Here 
on this beach let us seat ourselves, and take note of the occurrences, the time being the end of August. 
The wavelets chase each other in undulating lines, the sunbeams glitter on the smooth surface of the sea, 
and the gentle breeze tempers the heat of noontide. The sea-birds are on wing, wheeling and hovering all 
around, vociferous in their enjoyment, — their screams mingling into one harsh noise. Every now and then 
a Tern dips into the water, and emerges with a little fish in its bill, which it swallows without alighting. 
In the midst of all this bustle and merriment, there comes gliding from afar, with swift and steady motion, 
a dark and resolute-looking bird, which, as it cleaves a path for itself among the White Terns, seems a 
messenger of death. A few minutes ago he was but a dim speck on the horizon, or at least some miles 
away ; and now he is in the very midst of them, has singled out his victim, and is pursuing it. The latter, 
light and agile, attempts to evade the aggressor, mounts, descends, sweeps aside, glides off in a curve, 
turns, doubles, and shoots away, screaming incessantly the while. The Sea-Hawk follows the frightened 
bird in all its motions, which its superior agility enables it to do with apparent ease. At length the Tern, 
finding escape hopeless, and perhaps terrified by the Imminence of its danger, disgorges part of the contents 
of its gullet, probably with a view of lightening itself. The pursuer, with all his seeming ferocity, had no 
designs upon the life of the poor Tern ; and now his object is evident, for he plunges after the falling fish, 
catches it in its deseent, and presently flies off to attack another bird. In this way the marauder makes 
his rounds, exacting tribute from all who he thinks are capable of paying it, and not sturdy enough to resist 
oppression. The teaser never fishes for himself on such occasions, although his organization seems to fit 
him for aquatic rapine even more than that of the Tern or Gull. When satisfied with food, he retires to 
the distant bosom of the deep, or to some inlet or unfrequented part of the sand ; but his awakening 
appetite soon forces him to return, and, for hours together, he may be seen on wing, singling out a bird 
here and there, and pursuing it, or gliding swiftly, as if on urgent business, from one group to another. 
The pirate sweeps rapidly along on extended wings, which are considerably curved like those of the Gulls 
and Terns, the latter of which it resembles in its mode of flight, although it moves more directly, with 
