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PHOTOGRAPHIC STUDIES OF SOME LESS FAMILIAR BIRDS LXXXIX. GOSHAWK

Photographed by KURT ELLSTROM and JONAS SVENSK (Plates 37-40) Text by I. C. T. NISBET THE GOSHAWK (Accipiter gentilis) is of special interest as one of the very few birds of prey which occur on both sides of the Atlantic. It belongs to an extensive group of species of "gos­ hawks" (formerly placed in a separate genus Astur, but now merged with the sparrowhawks in Accipiter), which has an almost ubiquitous distribution in the Old World, with many species in Africa, southern Asia, the East Indies and Australia, The European Goshawk is the most northerly and the most widespread of all, and is the only member of the group which is found in North America—in this resembling the northernmost species of other genera of birds of prey, such as the (Aquila chrysaetos) and the {Circus cyaneus). It breeds from coast to coast in both continents, extending north of the Arctic Circle wherever there are suitable woodlands, and south to the Mediterranean, southern Russia, Japan and the northern United States, with other populations in the mountains south to Morocco, Tibet and New Mexico. Despite its wide distribution in Europe, however, it is little more than a vagrant to Britain, its recent attempts to establish itself in southern England having met with very limited success (Meinertzhagen, 1950; Hollom, 1957)- Like that of many other birds of prey, its past status here is confused and badly documented. It is now best known as a scarce visitor outside the breeding season, and as such has become much more frequent in recent years, especially in south-east England, where in some counties a few are now seen almost every year. Largely a resident species, the Goshawk has split into a number of subspecies, which differ rather widely in colour. The two races most likely to occur in Britain, A. g. gallinarum of west and central Europe and A, g. gentilis of Scandinavia, are both brown above, like female Sparrowhawks (A. nisus), but adults from south Europe are more slate-grey on the upper-parts, and those from Asia vary from brown through a number of shades of grey. There is also much variation in the colour of the under-parts, and the race A. g. albidus of N. E. Siberia is pure white, resembling the celebrated white goshawks of Australia !A. novaehollandiae). The American race, A. g. atricapillus, is particularly well-marked, the adult having blue-grey upper-parts, an almost black crown contrasting with a wide white eye-striae, and under-parts with greatly reduced barring, but although this plumage is unlike that

233 234 BRITISH BIRDS [VOL. LI

of any west European race, field-identification of vagrants here may not be reliable (cj. antea, vol. L, pp. 164-166). The European races are rather strictly resident—at Falsterbo, the famous hawk migration station in south Sweden, for example, this is one of the rarest of all birds of prey (Rudebeck, 1950)—but other races wander a good deal in autumn and winter, and the northern birds undertake fairly extensive southward migrations. The American race, indeed, is an irruption bird, occasionally invading the United States in large numbers in late autumn, and this tendency to wander is reflected in the occasional appearance of vagrants in Europe: in Ireland this race has occurred more often than the European races. It is interesting to note in this connection that each of the three twentieth-century records of the American race in Europe, mentioned in The Handbook, took place in one of the winters listed as invasion years by Bent (1937) and Broun (1945). The photographs give an excellent impression of the appearance of the species, the closely barred under-parts (plates 37 and 38), the banded tail (plate 38 upper) and the uniform dark brown upper- parts of the adults of both sexes forming a pattern closely similar to that of the female Sparrowhawk, a resemblance which is heightened in flight by the similar long tail and short, rounded wings. The Sparrowhawk is in fact the only species likely to be mistaken for a Goshawk in Great Britain, but the latter is a much larger bird—as illustrated by plate 37, which shows a male with a dead Hooded Crow (Corvus corone comix)—and can often be identified by size alone. However the females of both species are considerably larger than the males, and some female Sparrow- hawks look sufficiently similar to male Goshawks to call for much care in identification, especially if no other species is present to give a reliable comparative estimate of size. In these circumstances the onlv conclusive plumage feature of the adults is the white eye- stripe (plates 37 and 38), which is very hard' to see in flight except at close range, but the immatures are very different from any plumage of the Sparrowhawk in their unbarred under-parts with large drop-like streaks, a feature which is admirably shown on plate 40 and which can often be seen in a good view in the field. However, despite the dearth of positive field-marks, the beginner faced with his first Goshawk rarely has any doubt in recognizing it as an unfamiliar species, for in flight it really appears very different from the Sparrowhawk. The wing seems broader-based' and heavier, and except when the bird is soaring or in rapid turns the primaries are rarelv spread, so that it normally looks more or less pointed—a distinction illustrated bv Tinbergen in The Hand­ book, but shown more dearly by the sketches of Holstein (1942) and Hagen (19^2). Even more striking, the flight is much more active and manoeuvrable than a Sparrowhawk's, with a characteristically flexible wing-action, so that, as Tucker pointed out in The Handbook, the bird often looks more like a gigantic falcon than an Accipiter. VOL. LIJ GOSHAWK STUDIES 235

The Goshawk is a woodland species and, although a few wander into open country outside the breeding season, it is very easy to overlook. It hunts in the same manner as a Sparrowhawk, pursuing its prey in flight and threading its way through the trees with great dexterity, while in places where the undergrowth is too thick to follow mammals in flight it has even been known to pursue and catch them on foot (Bent, 1937). The prey is usually carried to a clearing or to an open space at the edge of the wood where the bird has a clear all-round view while eating, and plates 39 lower and 40 illustrate a characteristic habit of the species in choosing a tree-stump or similar elevation as a "chopping-block" on which to dismember the prey. Much interesting information on the feeding habits of the species has been given by Tinbergen (1937, 1955). Plates 38 and 39 upper show a typical site for the nest, usually at least thirty feet up in a tree, and normally built by the birds themselves, although nests of buzzards (Buteo spp.) and other species are occasionally adopted. The breeding of the Goshawk has been studied and described in great detail by Holstein (1942), and no-one interested in the species should fail to read this fine monograph, nor the more recent book by Kramer (1955), based on observations in Germany. The Goshawk has long been used for hawking, and accounts in the literature of its training and prowess possess a very respectable antiquity—see, for example, The Boke of St. Albans (Berners, i486). Indeed it shares with the Sparrow- hawk the distinction of being the subject of the first ornithological monograph ever written (Anon, 1575), while more than three centuries earlier the Emperor Frederick II had at least planned a similar book on the short-winged hawks, as a complement to his famous text-bo»k of falconry (Wood and Fyfe, 1943). In the Middle Ages, when the more exciting sport of with falcons was reserved to the nobility, the Goshawk was the bird of the yeoman, and in England it has always been used primarily for hunting (Perdix perdix), (Phasianus colchicus) and (Oryctolagus cuniculus), while good birds regularly kill hares (Lepus spp.). As illustration of the abilities of well-trained Goshawks, Bert (1619) describes a bird that killed eight to ten Partridges each day on the Sussex Downs ("to the great woonder of the worthy Knights and Gentlemen in those parts"), and Harting (1898) mentions a French bird which caught 600 Rabbits in two seasons, while one of Lord Lilford's Goshawks killed 300 Rabbits in three months (Trevor-Battye, 1903). However, the reputation of the species as a mere "kitchen-hawk" (Schlegel and Wulverhorst, 1844-1853) is not entirely deserved, for it can be trained to yield most exciting sport. According to the Bas- nama-yi Nasiri, a Persian treatise translated by Philpott (1908), and to Burton (1852), for example, Goshawks were regularly used in Persia and India for hunting such large game as cranes (Grus sp.), Great and Houbara Bustards (O. tarda and Chlamy- 236 BRITISH BIRDS [VOL. LI

dotis undulata) and Gazelles (Gazella sub gutter os a). The killing of the latter, which Burton describes in graphic fashion, was a feat unexcelled in eastern falconry. The Goshawk has often been regarded as one of the game- preserver's w|orst enemies, and its food has been extensively studied. Of 407 prey-items analysed by Hagen (1952) in Norway, 101 were mammals, including 35 Red Squirrels (Sciurus vulgaris) and 25 Hares (Lepus timidus), and the remainder birds, including 21 Corvidae of various species, 64 thrushes (Turdus spp.), no (Lyrurus, Tetrao and Lagopus), 35 Pheasants and 13 chickens. The prey shown in plates 37, 39 lower and 40, respectively a Hooded Crow, a Red Squirrel and a Jay (Garrulus glandarius), are thus typical of the food of the species in Scandinavia, but widely different preferences have been recorded in other parts of the world. Holstein (1942) mentions birds which specialized in domestic pigeons (Columba livia) or Black-headed Gulls (Larus ridibundus); the birds in southern England (Meinertzhagen, 1950) lived mainly on Woodpigeons (C. palumbus); those in Siberia and Alaska feed extensively on lemmings (Lemmus sp.). and Ptarmigan (Lagopus mutus), while the American authorities quoted by Bent variously record preferences for duck, chickens, rabbits, Red Squirrels and (formerly) Passenger Pigeons (Ectopistes migratorius). In the breeding season birds as small as Chaffinches (Fringilla coelebs) and sparrows (Melospiza) are sometimes eaten, but in winter, when the females hunt for themselves, the food taken is generally larger, and birds up to the size of Capercaillie (Tetrao urogallus) are regularly killed. It often hunts smaller birds of prey; indeed in Holland—where, with relaxation of persecution, the Goshawk has recently increased, even spreading into town parks—Tinbergen (1955) has attributed the corresponding decrease of the Sparrow- hawk to the depradations of its larger cousin. On the other side of the scale, a Goshawk has once been found in a Golden Eagle's nest (Bent, 1937), and Jays sometimes steal the eggs, but the species has only one serious enemy—Man, in his r61es of falconer, game-preserver, chicken farmer and "sportsman". The Goshawk is a wily bird, and there are several cases on record where campaigns to exterminate it have resulted merely in the destruc­ tion of harmless species such as Common or Red-tailed Buzzards (Buteo buteo or B. jamaicensis) or Ospreys (Pandion haliaetus), but it is unlikely that this fine bird will ever become established in Great Britain while present methods of game-preservation are practised.

REFERENCES ANON, (ca, 1575): A perfect booke for kepinge of Sparhawkes or Goshawkes. Edited J. E. Harting, London, 1886. BENT, A. C. (1937): Life-Histories of North American Birds of Prey, Order F'alconiform.es (Part I). Washington. VOL. LI] GOSHAWK STUDIES 237

BERNERS, J. (i486): The Treatyses pertyninge to Hawkynge, Huntynge and Fysshynge with an Angle, St. Albans. BERT, E. (1619): An Approved Treatise of Hawkes and Hawking. London. BROUN, M. (1945): Hawks Aloft: the Story of Hawk Mountain. New York. BURTON, R. F. (1852): Falconry in the Valley of the Indus. London. HAGEN, Y. (1952): Rovfuglene og Viltpleien. Oslo. HARTING, J. E. {1898): Hints on the Management of Hawks. London. HOLLOM, P. A. D. (1957): "Goshawk", in "The rarer birds of prey: their present status in the British Isles". Brit. Birds, t: 135-136. HOLSTEIN, V. (1942): Dueh0gen. Biol. Studier over Danske Rovfugle I. Copenhagen. KRAMER, V. (1955): Habicht und Sperber. Wittenberg Lutherstadt. MEINERTZHAGEN, R. (1950): "The Goshawk in Great Britain". Bull. B.O.C., 70: 46-49. PIHLPOTT, D. C. (1908): The Baz-nama-yi Nasiri: a Persian Treatise on Falconry. London. RUDEBECK, G. (1950): "Studies on bird migration, based on field studies in southern Sweden". V&r F&geharld, Suppl. I. Lund, Sweden. SCIILEGEL, H., and WULVERIIORST, A. H. VERSTER DE (1844-1853): Traiti de Fauconnerie. Leiden & Diisseldorf. TINBERGEN, L. (1955): Levende Natuur, 58: 211-216. -— , and TINBERGEN, N. (1932): "Waarnemingen aan roofvogels en uilen". Levende Natuur, 36: 69-80, 98-104, 131-137. TREVOR-BATTYE, A. (1903): Lord Lilford on Birds. London. WmiERBY, H. F. et al. (1938-1941): The Handbook of British Birds. Vol. III. London, WOOD, C. A. and FYFE, F. M. (1943): The Art of Falconry, being the De arte venandi cum avibus of the Emperor Frederick 11 of Hohenstaufen. Stanford, California. PLATE 37

Kurt Ellstrom and Jonas Svensk ADULT MALE GOSHAWK (Accipiter gentilis) AND PREY: HALSINGLAND, SWEDEN, APRIL 1956 Note the whitish under-parts closely barred with dark brown, and the grey-tinged brown back and wings, while comparison with the Hooded Crow (Corvus corone comix) which the bird is holding indicates the size. As with many birds of prey, male Goshawks are smaller than females, but here one can see how much larger even the males are than female Sparrowhawks (A. nisus), which they closely resemble in plumage except for their more conspicuous eye-stripes (see page 234). PLATE 38

Kurt Ellstrom and Jonas Svensk MALE GOSHAWK (Accipiter gentilis) AT NEST: SWEDEN, 29T11 JUNE 1953 The eye-stripe is over-emphasized here by the dark shadow on the face (cf. below), but one can see that the banding on the tail is less conspicuous than in the juvenile (plate 39 lower). Here the young had left the nest, but the adults continued to bring food for them there for some time.

Kurt Ellstrom and Jonas Svensk FEMALE GOSHAWK (Accipiter gentilis) AT NEST: SWEDEN, 25TH MAY 1953 The pure white under tail-coverts, which are spread very prominently in the spring display-flights, are particularly well shown here, as is the eye-stripe. Typical clutches consist of three or four eggs, which in Denmark and Sweden are laid in late March and April. PLATE 39

Kurt Ellstrom and Jonas Svensk YOUNG GOSHAWKS (Accipiter gentilis) IN NEST: SWEDEN, 2IST JUNE 1953 At first the male brings all the food and the female divides it up, but later both sexes hunt. Incubation and fledging last about five and six weeks respectively. In this brood the bird on the left, a male, is older (note the feathering of the "trousers") than the other two, both females.

Kurt Ellstrom and Jonas Svensk JUVENILE FEMALE GOSHAWK (Accipiter gentilis): SWEDEN, SEPTEMBER 1955 Note the broad bands on the juvenile's tail (cf. plate 38 upper). Goshawks hunt mainly in woodland and, in addition to a wide variety of birds, kill many mammals, particularly Red Squirrels (Sciurus vulgaris), one of which is shown here on the "chopping-block" (see page 235). PLATE 40

Kurt Ellstrom and Jonas Svensk JUVENILE FEMALE GOSHAWK (Accipiter gentilis): HALSINCLAND, SWEDEN, SEPTEMBER 1955 The juvenile is paler above and the feathers are tipped with rufous, while the warm buff under-parts are marked with brown drop-shaped streaks, shown clearly here : these are retained throughout the first winter and are a distinction from the Sparrowhawk (A. nisus) which is always more or less barred. Here, and in plates 37 and 39, is illustrated the bird's habit of eating its prey—in this case a Jay (Garrulus glandarius), a common food item (see page 236)—in an open area where an all-round watch is possible,