The Hen Harrier Read online

  Throughout the first year young male Hen Harriers remain in brown plumage, similar to females. According to the Handbook of British Birds, however, moult into grey plumage occasionally begins as early as March of the first year, but generally the first grey feathers on head, breast and greater wing coverts do not appear till July or August.

  A breeding male, which I presumed to be just over one year old, was parti-coloured on 16 August; grey on head and breast, with prominent red-brown spots or streaks on the flanks and belly, two or three new black feathers among the old, brown, barred outer primaries, and the tail had one or two new grey feathers. From above, the wings showed a grey middle area, caused mainly by the new greater coverts. Most of the back and scapulars still looked dusky brown, making the white rump conspicuous. I saw this bird well enough to establish that its iris colour was not yellow or light at all. I could say positively that it was dark but not precisely what colour. Montagu, in 1805, noted that his captive yearling male had ‘dull yellow’ eyes by June, changing to orange by 20 August, but Eddie Balfour gave the iris colour of one-year-old males in the wild as bright yellow, with no subsequent change.

  Hen Harrier, female

  Hen Harrier, male

  I have examined a range of skins of males, not one of which was of known age, but a bird killed in February matched closely with a February bird preserved by Eddie Balfour and known to be 20 months old. These specimens suggest that throughout their second winter male Hen Harriers are distinctive enough to be aged fairly accurately. The most striking feature of these second-year birds is the very dark area on the scapulars and mantle which contrasts with the mainly grey wings and tail. The wings are, in fact, much less pure grey than in older males but they are quite grey enough for the contrast mentioned to be picked out easily at considerable distances. When watching birds at a winter roost I have seen many males in this plumage. In some cases it may not be possible to decide whether a fairly ‘dark-backed’ male is in its second or third winter, as even third-winter birds may show appreciably more contrast between ‘back’ and wings than older birds.

  There are really three plumage features which indicate that a male is a relatively young bird: (1) dark brown-tinged mantle and scapulars; (2) red-brown spots and lines on flanks and belly; (3) a patch of buff and brown streaks on the nape. I do not know at what age all these features are lost. A high proportion of skins of ‘grey’ males show the streaked nape patch and it appears in an old illustration of an adult male. I suspect that birds which completely lack this feature are at least four or five years old. As Anthony Buxton (1946) noticed in his Norfolk Montagu’s, there is a great range of variation in the aesthetic beauty of individual Hen Harriers, especially males. Very many of these fall sadly short of the perfection of really old males with their immaculate pattern of blue-grey, white and black. The latter retain the merest wash of brown on some of the long scapular feathers, only detectable at close range. Montagu, who originally demonstrated the moult of a captive first summer male from brown to mainly grey plumage, said that this took three to four months and was completed by mid-October.

  Identification plates of grey males in flight are sometimes misleading on the colour of the trailing edge of the wing. This varies according to age. In older males this border is grey on the white underside and absent altogether on the upper surface. In younger males it is darker grey below, often looking blackish in the field, and there is a similar but much fainter border above.

  There is great variation in the ground colour of mature females. Eddie Balfour found that the palest and most grey-brown birds were among the oldest but there is probably much variation independent of age. An important point to remember is that freshly-grown feathers are darker than old ones and, therefore, the same bird varies in appearance; and moult makes the upper parts of females look patchy, dark and light brown. The most important guide to age in females is the iris colour, as Balfour demonstrated. His original assessment, in 1970, was as follows: pale chocolate at one year, amber at three to four years, and bright yellow at six to seven. On close examination he found that the brown in a one-year-old bird was present as numerous small flecks on a background of yellow. In 1974 he told me that the above assessment needed qualifying as he had found that three- to four-year-old females occasionally had bright yellow eyes. He also had some evidence that very old females had the palest yellow eyes.

  Albinism and melanism in Hen and Montagu’s Harriers

  Albinism

  Bryan L. Sage (1962) listed the British species in which albinism and melanism had been recorded. The only harrier in which albinism was known was the Hen Harrier. Melanism, among British harriers, was then only recorded for Marsh and Montagu’s, the latter having a well-known melanistic form.

  Wholly or largely white Hen Harriers have been killed at least six times in Scotland. One has almost certainly been seen in Wales, and one has been killed in Ireland. The details of these are as follows:

  1‘A beautiful female’, shot, Loch Carron, Ross-shire, May 1870. Mentioned by Robert Gray.

  2‘A very fine albino’, sex not given. Preserved at Barrogil Castle, Sutherland. Before 1887. Mentioned by Harvie-Brown and Buckley.

  3Juvenile, shot in Orkney, August 1937. Seen by Eddie Balfour earlier that summer. Now preserved as a mounted specimen in Stromness Museum. Almost all white except for brown nape, sides of head, streaks on upper breast and wash on inner secondaries; white claws.

  4Male, adult, shot in Orkney, June 1938. Skin now in the Royal Scottish Museum, Edinburgh. I have seen this specimen; the entire plumage is almost pure white and it must have been a most beautiful bird in life. Eddie Balfour told me that he had watched the bird in 1938 and that it disappeared during a few days in June when he was absent from the island. It was evidently killed by someone on behalf of the late F. Nisbet of Pitlochry, whose collection was left to the museum. Some 20 years later Eddie Balfour was looking at the harrier skins there and so discovered the fate of the bird whose disappearance had always been a mystery to him.

  5Male, age unknown, Perthshire, 1940s. The late Dr J. W. Campbell told me that he had seen this bird which was virtually all white. Believed shot.

  6Male, preserved at Treumland House, Orkney. I have no details.

  Eddie Balfour told me that in Orkney (in over 40 years) he had seen about twelve birds which had had a ‘large amount’ of white. He remembered one other pure white bird which was alive when he was a boy, before 1920. He had seen many birds with a crescent, only, of white and over twenty with traces of white. Birds with white claws are fairly common. It is therefore clear that there is a strong tendency towards albinism in the Orkney population and it is, of course, possible that all the specimens described originated from Orkney. Sage cites inbreeding as one cause of albinism and this might be true in Orkney, but the recent catching and marking of breeding adults there has shown that only 23% of the 83 caught had been ringed as young on the island, though a large proportion of the young have been ringed for many years; it is therefore likely that immigrants are continually mixing with the island stock. There is, presumably, some form of hereditary albinism in the Orkney population, but Nick Picozzi reports that he found no trace of albinism in 44 young and 24 adults in 1975.

  7Sex unknown. On 31 May 1970, D. J. Bates, R. J. McCann and J. R. Mullins had a brief view of a creamy or buffish white harrier, almost certainly a Hen Harrier, over a young forest plantation in North Wales.

  8Male, Ireland; shot in the north of Co. Tipperary, early 1971; examined in the flesh and photographed by David Scott. It was almost pure white with a few dark dots on the head and a trace of grey on the wings.

  None of the birds listed can be described, positively, as true albinos; there are no records of iris colour. Frank King has seen a male in Ireland with two white primaries on one wing.

  Melanism

  Sage said that this was certainly a much less frequent occurrence than albinism, but went on to distinguish between ‘normal melanism’ which
is found regularly in some dimorphic (or polymorphic) species, such as the Montagu’s Harrier, and ‘abnormal melanism’, which occurs in isolated individuals of species with no melanistic phase but which occasionally becomes established and replaces the normal form. There is no evidence that the Hen Harrier has a normal melanistic phase, but an example of melanism has kindly been reported to me by David L. Clugston. This was first seen on 6 July 1968, when the bird was a downy chick in a brood of three (the other two normal) in a nest in North Wales. David Clugston’s photograph clearly shows that the melanistic chick was sooty grey, much darker than the others. Very fortunately, all three chicks fledged and were seen on 28 July by D. L. C., J. R. Mullins, R. J. McCann and Dr R. J. Raines. The melanistic juvenile was described by D. L. C. as follows: ‘Whole body, wings and tail plumage brown-black showing no sign of pale or white rump. At close range, wing coverts, tail and upper parts showed grey-brown tinge. Legs bright orange-yellow. The other two juveniles resembled the female with prominent white rump, but underparts rich red-brown, heavily streaked black-brown’. Good views were obtained of both parents. The female was typical but the male was considered less so; no white rump was apparent and the male also had a few dark feathers ‘near the hind wing . . . and in the tail’. These perhaps might have been due to comparative youth, but not the absence of a white rump. Strangely, also in July 1968, I saw a chick in a Galloway brood of three which was appreciably darker than its fellows when in down, but it appeared normal when feathered.

  On 29 June 1976, again in Galloway, one chick in a brood of three was dark leaden-grey at the downy stage, strikingly darker than the others. It appeared to be a female and when almost fledged its plumage colour differed from the others (both males) in the following ways: all the white upper tail-covert feathers had conspicuous drop-like dark brown mesial streaks; the ground colour of the underparts was richer red-brown and the streaks heavier and darker; the general colour of the upper parts was darker brown, almost black on the primary wing feathers and nearly obscuring the cross bars; the rufous-buff on ruff, nape and wing-coverts was darker and so less prominent; the normal cinnamon-buff tail bars were replaced by distinctly deeper more rufous colour. Although this bird had the dark-brown iris colour of a female the legs were not as thick as expected, and the possibility that it was a male was not conclusively ruled out. It appeared to be an example of partial melanism and it seems possible that this may have had a darkening effect on the iris colour.

  The melanistic form of Montagu’s Harrier is generally brownish-black with a greyish tinge on the throat and upper parts, including the wings and tail. Some are more or less coal-black—Ryves (1968) saw a ‘magnificent coal-black female’ at a nest. In this form both sexes are without any white on the rump. It is notable that neither Weis in Denmark nor Buxton in Norfolk, both of whom saw many pairs of Montagu’s over a number of years, made any reference to melanistic individuals, but in south-west England, Ryves and others noted them fairly frequently, and Delamain described melanistic individuals in France. Lawrence G. Holloway informs me that on many visits to Andalusia, Majorca and Morocco, during which Montagu’s Harriers were often seen, he had no records of melanism. He did, however, see one apparently partially melanistic male near Zahara (Provincia de Cadiz) in September 1971.

  * Nieboer (1973) found two specimens of juvenile Hen Harriers (both females) from East Asia with nearly unstreaked underparts like young Marsh Hawks. This clearly raises the possibility that the report of an immature Marsh Hawk (C.c.hudsonius) at Cley, Norfolk, in winter 1957–58 (Wallace, 1971 et seq), might have referred to an immature Hen Harrier (C.c.cyaneus). I have not read any plumage details of a more recent unconfirmed report of a Marsh Hawk at Saltfleetby, Lincolnshire, 18–30 November 1973 (British Birds 67.2).

  PART 1

  THE HEN HARRIER

  CHAPTER THREE

  History of the Hen Harrier in Britain and Ireland

  The decline

  The inhabitants of these islands must have been familiar with the appearance of Hen Harriers long before any written reference was made to the species. It may be speculated that, in mediaeval times, the very extensive forest cover limited the amount of suitable habitat in many parts of the country and Hen Harriers may well have increased as more forest disappeared. There is evidence that they were already well-known in the 16th century.

  Writers, however, were not aware that the grey male and the brown ringtail were the same species. No doubt illiterate countrymen who had found the birds’ nest could have enlightened the scribes on this point. The earliest written reference to the Hen Harrier that I have seen occurs in a colourful poem, in Middle Scots, by William Dunbar. This poem, ‘The Fenyeit Freir of Tungland’ (Tongland, in the Stewartry of Kirkcudbright), was written about 1504. In it, over 20 kinds of birds are named as attacking the false Italian abbot, John Damian, when he made his disastrous attempt at flying with a pair of ‘wingis of fedderis’. According to Bishop Leslie he ‘flew of the castle wall of Striveling, but schortlie he fell to the ground and brak his thee [thigh] bane, bot the wyte [blame] thereof he asscryvit to that thair was some hen fedderis in the wingis, quhilk yarnit [which yearn for] and covet the mydding [midden] and not the skyis’. Dunbar’s sympathy was all with the birds whose element was being invaded, though his main concern was to ridicule a personal enemy who had won favour with the King for his alleged skills with drugs and medicines. There is no doubt that in the following passage from the poem, ‘Sanct Martynis fowle’ was the male Hen Harrier—Le Busard St Martin survives today as the French name for the species.

  The myttane and Sanct Martynis fowle,

  Wend he had been the hornit howle,

  They set upon him with a yowle

  And gaif him dint for dint.

  The name ‘myttane’ has not been ascribed to any particular bird of prey, merely ‘some kind of hawk’ according to dictionary definitions, but it is probable that Dunbar was referring here to the ringtail harrier, the female. In making this suggestion I am influenced by the fact that in this and other poems he identifies no less than nine kinds of eagle, hawk or falcon specifically—Golden Eagle, Sea Eagle, Sparrowhawk, Goshawk, Peregrine, Merlin, Kestrel, Buzzard and Kite—and the one obvious gap would be filled by ascribing ‘myttane’ to a ringtail harrier. It seems to me very unlikely that a man so knowledgeable on birds of prey would have used ‘myttane’ in a purely general sense. The linking of the ‘myttane’ and ‘Sanct Martynis fowle’ in a joint assault, as on ‘the hornit howle’, strongly suggests that Dunbar had observed a pair of harriers diving at a Long-eared or perhaps an Eagle Owl exactly in the manner that has been exploited by shooters and research workers in modern times.

  Dunbar was probably brought up in the shadow of the Lammermuir hills, in East Lothian, where Hen Harriers must then have been an everyday sight—they were still breeding there into the 19th century. As an envoy of King James IV of Scotland he is known to have visited France and may have seen them there as well—and possibly seen Eagle Owls used as lures. There, also, he might have learned the l’oiseau St Martin, derived from their customary arrival as migrants in France about 11 November, St Martin’s day.

  The first real description of the Hen Harrier in the British Isles was written by Dr William Turner, in his Avium Praecipuarum of 1544, the first printed bird book. James Fisher has called Turner the father of British Ornithology. A. H. Evans, author of A Fauna of the Tweed Area (1903), translated Turner’s Latin into English. Turner’s object in writing his treatise was to determine the principal kinds of birds named by Aristotle and Pliny, but he added his own first-hand observations which reveal him as a percipient field ornithologist of his time. Of the Hen Harrier he wrote (Evans’ translation): ‘The Rubetarius I think to be that Hawk which English people name Hen Harroer. Further it gets its name among our countrymen, from butchering their fowls. It exceeds the Palumbarius* in size and is in colour ashen. It suddenly strikes birds when sitting in the fields upon the ground, as well as fowls
in towns and villages. Baulked of its prey it steals off silently, nor does it ever make a second swoop. It flies along the ground the most of all. The Subbuteo I think to be that hawk which Englishmen call Ringtail from the ring of white that reaches round the tail. In colour it is midway from fulvous to black; it is a little smaller than the Buteo, but much more active. It catches prey in the same manner as the bird above’. Turner, therefore, did not recognise the relationship between the (male) Hen Harrier and the ringtail. His note is, however, important in other ways; it leaves no doubt about the origin of the name ‘Hen Harrier’ and proves that in the 16th century it was already an unpopular predator, ripe for persecution because of its partiality for poultry, and not averse to hunting among human habitation, as it still does in Orkney and the Outer Hebrides. All ‘ashen’ plumaged harriers were then known as Hen Harriers, the Montagu’s not being distinguished until Montagu described it in 1802. Sir Robert Sibbald, in his Scotia Illustrata (1684), jointly lists the Subbuteo (Ringtail) and Buteus albus (White Hawk) and has some claim to be the first writer to recognise the relationship between the male and female Hen Harrier; at least he says that some people consider them the same kind of bird.

  How numerous or widespread the Hen Harrier may have been in these distant times is a matter of conjecture. It might have been otherwise had it been valuable to falconers, like the Peregrine—one Peregrine eyrie, still occupied in the 20th century, is recorded as far back as 1564, and others can be traced back over 300 years. Before the period of large-scale enclosure and improvement of ‘wasteland’, in the 18th–19th centuries, there was clearly a vast amount of heath and moorland, even in regions like the English Midlands. W. G. Hoskins (1955) considered there were about seven million acres of ‘heaths, moors, mountains and barren lands’ in England and Wales alone. Such ground, with the extensive undrained bogs and marshes, must have provided much greater areas of suitable nesting country for harriers than have ever existed since. There is plenty of evidence, as I shall show, that the bird was common in many places even at the beginning of the 19th century, when land improvement and the killing of predators in the interests of game preservation had begun to take effect, and it can hardly be doubted that it was much more plentiful still a hundred or so years earlier.