The Hen Harrier

by Donald Watson

  By mid June, after we had tried out some new, more distant observation points, we were back at the original spot. The hen sometimes came over and circled us, yikkering, but the business of feeding the young was not being interrupted by our presence. By now the hen, in good weather, was no longer brooding the chicks for much of the day, and she often sailed about over the road and would fly as far to meet the cock for the food pass. The pair must have become obvious enough to passers-by but, apart from the shepherds and keepers, few people took any notice of them. We were concerned one day when a boy left his bicycle on the road and made great speed for the hill. For 20 minutes we boy-watched anxiously, then laughed at ourselves as he reached the summit and came smartly down again, perhaps getting in trim for the school sports, and certainly not interested in birds’ nests.

  We could now make out the actions of the female as she fed the young. Surprisingly, although this nest was watched for 43 hours after hatching we never had much evidence of hunting by the hen, not even when the young were fledged. For instance, on 7 and 8 July, when they were 5-5½ weeks old, during seven hours of watching, all the prey came by way of the cock, either by food passes to the hen and once, probably, to a flying youngster, or by direct drop to the young still using the nest as a base. The cock at this nest never flagged in his attentions, as many do towards fledging time, and the hen was more zealous than some in her role of guardian. So the division of labour was more like that observed by Ryves, at his Montagu’s nests, than is usual at a Hen Harrier’s nest when the young are large and the hen is hunting at least as much as the cock. (Henning Weis and Schipper each found that female Montagu’s often hunt before the young can fly.) Consistent with the cock continuing to do most of the hunting, nearly all the prey looked small, as far as could be judged.

  The hen, always bold, reached a peak of aggression when the young were about three weeks old. Head-covering on visits of inspection became prudent. More than once, at this stage, she clawed hat from head, and a shepherd claimed that she dived so fiercely at a keeper, ‘looking for pluckings’, that he came away quickly. She was succeeded in following years by other aggressive hens, so that, for some years, I thought this behaviour was the rule at almost every nest. Further experience has shown that many hens show little or no aggression towards man.

  On 20 June, in the early morning sun, the hen was spending most of the time perched on or near the old thorn tree, sunning herself and preening, but very much on guard. Crows were chased vigorously from the nest area. At this period of the nesting cycle it is fairly easy to locate nests by watching a hen, as she is so inclined to perch, conspicuously, near the nest, and the young require frequent visits with food. A food pass at 07.05 was the earliest seen at this nest, the young being fed after the hen had spent two minutes plucking the prey in the heather. Watching a nest from a hide, years later, I was surprised to find that a hen was still tearing up plucked prey and feeding it to a chick 31 days old. Intervals between visits with prey were now sometimes as short as a quarter of an hour. Intervals of 5–10 minutes between some visits were recorded in later years, strongly suggesting that a brood of fledglings had been raided in quick succession. When the young were big the hen often ignored the cock’s arrival as he dropped prey direct to the chicks.

  We visited the nest on 20 and 29 June, and 2 July. In Chapter 6 I have detailed the changes in the appearance of chicks as they grow from birth to fledging. On this first experience I was especially struck by the rapid feather growth during the final ten days. On 2 July we went, confidently, to ring the brood, having decided in favour of this rather late in the season. The eldest chick would be hardly more than four and a half weeks old and we did not expect any to fly till they were over five weeks: we had not the benefit of Eddie Balfour’s papers on the breeding cycle.

  On the dull, damp morning we were up at the nest soon after 07.00 hours, Bobby Smith, young Lars Svensson and I. Lars, now famed far beyond his native Sweden as an ornithologist, had come to us to improve his English, with the strong proviso that he would get some bird-watching. We had chosen an hour when we were unlikely to attract attention from the road. But inexperience caught us out again—one of the brood flew as we approached and could not be found again. Although the other three were no problem, that morning taught the lesson that young Hen Harriers, if disturbed, can often fly at little over 30 days, and ringing should never be left so late. Nor were we too happy at causing a premature flight, even though the hen, for once ignoring us at the nest, immediately flew after the escaper.

  Apart from a few flecks of grey down on wings and head, the young harriers had become superficially like darker and more richly coloured replicas of their mother. A host of details were rapidly noted or sketched, as the young crouched on the flattened remnants of the once tidy nest, the almost purple bloom on their backs emphasised by the bronze-green tangle of heather that overshadowed them. Their most arresting features were their, now brilliant, chrome yellow legs and their beautiful tails, banded creamy-red and sepia, some partly-grown feathers still looking like little darts in their blue sheaths. The bird which had flown was probably a male and the others were two females and a male, sexed quite easily from iris colour and leg thickness. The grey-eyed young male was slimmer both in body and leg than his sisters. In the steamy weather, the nest was infested with flies, and this brood were more heavily afflicted with fleas and flat flies than any I have seen since. Even at this late stage the hen had removed uneaten remains of prey and the only food in the nest was an apparently adult Skylark, which must have been the prey we had seen the cock drop at the nest before we left the road. It had been delivered plucked. In the heather near by, a very young Whinchat, not very fresh, was also uneaten.

  Interest did not cease after the young could fly. For at least a week after fledging the young birds often flew back to the nest to find prey dropped there by either parent. They were extremely difficult to spot from a distance when they sat, for long periods, well scattered about the hill face, but often they could be seen circling or diving at one another on the wing. At this and later nests I saw recently fledged young fly up to catch prey dropped by the hen, as in a food pass. Sometimes they were too slow and did not get near enough to the hen to make the catch.

  The hen, ferocious as ever, became particularly angry when sheep happened to come close to any of her brood, often diving at a sheep’s head for minutes at a time and even striking with her feet. The sheep seemed unimpressed and the shepherd was merely amused. The whole family stayed about the nesting hill until at least mid-July, and harriers were still to be seen not far away until the end of the month. Then, as generally happens, the nesting area was deserted, though I saw a single young bird quartering the brown bracken at the roadside on 9 October—as likely, at that date, to be a wanderer from elsewhere as one of the local brood. It may have been no coincidence that, in November of this first year of proved nesting, I had my first sighting of a Hen Harrier at the bog, five miles away, where in later years a communal winter roost was established.

  CHAPTER ELEVEN

  Moorland Nesting: 1960–68

  After the successful nesting in 1959, I looked forward to the return of a pair in the following season. In view of the reports of increase further north, there seemed good prospects for the establishment of a breeding population in Galloway over the next few years. This did, indeed, happen, but much more slowly and hesitantly than might have been anticipated.

  On 8 February 1960, a male was seen near the old nest site, and on 14 March I saw a ringtail, probably a female, there. Then, on 4 April, came a shock. Almost all the long heather on the slopes of the ‘Lion’s Head’ had been burnt in an uncontrolled moor fire on 30–31 March. Looking at the bare blackened hillside I despaired of a nest that year. On that fine spring morning nothing looked promising for the harriers. Close at hand, men were working on road improvement, two boys with a gun were on the next hill and, just over a mile away, I could see the big red forestry plough turning u
p long lines of glistening peat. Yet, as I was to learn many times over, the magnetism of last year’s nesting ground is a most powerful force in the life of the Hen Harrier. Ryves (1948) has told how, in Cornwall, a pair of Montagu’s Harriers returned, to his amazement, to nest in the one small, unburnt patch of bog myrtle in a marsh devastated by fire. But I had not read this, and when I spotted a pair of Hen Harriers quartering the burnt heather slopes by the old site, I was astonished and delighted.

  Because we had found the nest late in the incubation period in 1959 we had so far seen nothing of display, courtship or nest building. At once I began to consider the possibilities of a nest in one of the few oases of old heather which remained. At least, it seemed, the choice was so narrow that there would be no problem in locating a nest if one should be built. That first day’s watch in 1960 is still one of my most vivid memories of the birds. They were surely the same pair as before, the cock translucently pale and clean grey, the hen big, richly-coloured and yellow-eyed. When they alighted close together among the charred, blue-black heather stalks, the whole made an arresting, even startling, colour spectacle.

  The pair did not, after all, choose one of the obvious heather clumps on the old hill for their nest. Instead, they moved across the burn, into a patch of sparser heather and bracken on a lower adjoining slope that was in dead ground from where I had been watching. On 1 May, Louis Urquhart joined me in a final attempt to pinpoint the nest. It was the beginning of a long partnership in harrier watching, for which we had equal enthusiasm and patience, and to which Louis brought the astuteness of a first-rate field ornithologist, tempered with salutary caution, when there were problems of nest finding or interpreting features of the birds’ behaviour.

  The hen, in fact, had begun to incubate before the end of April—the first chick hatched about 27 May—but the behaviour we watched on 1 May gave the impression that the nest-site was still being selected. The pair gave a beautiful exhibition of slow-motion circling flight, keeping close together, the male always a little above his mate, who sometimes almost stalled when low over patches of deep heather, as if inspecting them as likely nesting places. For half an hour or so they seemed to float in the air with scarcely a wing-beat. Both were noisy, bursts of yikkering alternating with the squealing food call. Earlier, we had seen the cock arrive with prey, but there was no food pass. Instead, the hen flew at him as he was plucking the prey and seized it on the ground, literally bowling him off it. All that spring there were no ‘skydancing’ displays. Later experience taught us that it was unusual to see these performances when a pair had no other harriers as neighbours, and it was often a young male, seeking to establish himself, who gave the most intense displays.

  The best place from which to observe this nest proved to be a steep gully beyond the burn, reached by almost a mile of devious walking. One of the delights of this hide-out was its remoteness from the road. The tributary burn which flowed down the gully was steep-sided, with ivy, heather and blaeberry clinging to the rock faces, and a straggle of deciduous trees, rowan, oak and ash. From here came the songs of Willow Warbler, Mistle Thrush and Chaffinch, and we saw much of the bold Ring Ouzels whose nest we found in a later year on a heathery scar of rock. Watching the Ring Ouzel pair feeding chicks, we learned that a hen can be almost as white-chested as a cock, quite unlike her text-book image. Short-eared Owls and Buzzards were never far away, and it was interesting to compare the cock harrier’s reaction to the two species. The Owls, which had a nest 250 metres in front of the harriers’, hardly bothered the harriers, but whenever a Buzzard appeared the cock harrier pursued it and dived at it relentlessly.

  The land where the harriers nested in 1960 was under different ownership from the 1959 site, but an approach to the landowner early in the season, happily, met with a sympathetic response and strong instructions were given for the nest’s preservation. It was a rather exposed nest, and the three chicks which hatched from a clutch of five, had to rely on the growth of bracken among the heather for shade on hot days. On 24 June, a four week old youngster bounded away when the nest was visited and was not easily settled again. When the young were nearly fledged, the cock became increasingly demonstrative, and began his deep-toned yikkering in fairly low level flight as soon as I came within 500 metres of the brood. On 9 July, Langley Roberts and I saw them flying strongly. A female from this brood was the first Galloway-ringed harrier to be reported. Its remains were found, bird ‘apparently shot’, 145 kilometres NNE, at Sherrifmuir, Perthshire, on 19 September 1961.

  In the spring and summer of 1960, I looked at a number of other possible nesting grounds in south-west Scotland and followed up any promising reports. A long watch in the young forest (Area C) produced no proof that a pair was breeding there, but visits to a large grouse moor in a neighbouring county, on the strength of a report that a clutch of Montagu’s Harrier’s eggs had been taken there, resulted in the discovery of a nest which proved to be a Hen Harrier’s. The Montagu’s identification was presumed to be mistaken, and the nest I found with five eggs on 23 June was probably a repeat by the robbed pair. This nest was the only one I have watched closely on a highly-rated grouse moor. There, long ago, King Edward VII had been one of the guns accounting for some prodigious bags. The late date of the nest meant that the young might be taking their first flights just as the grouse shooting started, so their chances of survival seemed minimal, especially as the nest was just below a line of butts. But, in 1960, Hen Harriers were rare birds in southern Scotland—no nest had been found in that district since the 19th century—and both landowner and keeper seemed content to accept them as protected birds. Unfortunately, such an outlook did not persist for long when Hen Harriers returned to the locality in later years.

  At this nest I had my first experience of a cock Hen Harrier breeding in brown, first year plumage. I wrote to Eddie Balfour about this and learned that it was fairly common in Orkney. Because I had been led to believe that the birds might be Montagu’s, specific identification proved difficult at first, as brown plumaged harriers are notoriously confusing. It was one of the few nests where the cock was bolder than his mate, so I soon had a close view of him in flight, but never of her. Had he three long primary feathers, or four? I counted them many times as he flew swiftly overhead and was reasonably satisfied that he had four, and so must be a Hen Harrier, but he was distinctly a more slightly built cock than the one I had been watching nearer home, and just possibly slim enough for a Montagu’s. A knowledgeable friend who saw the birds kept an open mind. No doubt it would have been easy with a first year cock Montagu’s for comparison, but I must admit that total certainty came only when the feathered chicks showed the diagnostic, streaked breasts of young Hen Harriers. Measuring the eggs was not quite conclusive.

  Years later, when looking at one of Jim Young’s flight photographs of a known female Hen Harrier, I was startled to find that she had only three long primaries on each wing—correct for a Montagu’s—and no obvious gaps left by moulted feathers. Yet the explanation, in this instance, had to be moult, and the presumed loss of the innermost (fifth) long primary was very difficult to detect.

  The grouse moor nest was on comparatively high ground, at just over 300 metres, though the actual site was in a hollow of deep bracken and heather above a burn. At that time, the landscape was heather moor as far as the eye could see, showing the patchwork of varied colour and texture made by moor burning. This had been beneficial to Golden Plover, as well as grouse. It was an incomparable setting for harrier watching on clear days, when blue cloud shadows were flung loosely across the madder brown slopes of the big hill beyond the burn, but the brown cock harrier was a poor substitute for the silver grey bird at the other site. Our greatest excitement came when we encountered a cock Marsh Harrier not far away, a reminder that in days long past this species nested on upland bogs. I often used to ponder the irony that, but for grouse shooting, most of what I liked best in this landscape would disappear and be replaced by conifer forest, or s
omething worse.

  Once again there was a pair of Short-eared Owls nesting within a few hundred metres of the harriers. The moor was virtually treeless, yet Willow Warblers had young in a brackeny hollow, ten metres from the nest. A pair of Merlins—the cock diving at the harriers—and Ring Ouzels were other neighbours. Crows were notably scarce on this keepered ground.

  In early August, when the young harriers were almost fledged, I was surprised to find a bulky platform of stout heather twigs, like an unshaped nest, built less than four metres from the nest itself. Both were being used as feeding places. I found similar constructions beside nests in later years but none as substantial as this. One day, the keeper accompanied us to the nest and admired the young harriers. It was evident that they were being fed, to some extent, on grouse, but he did not think this would have an important effect on his very well-stocked beat. By August the cock was partly grey on the body, noticeably on the new greater wing coverts, and had grown two or three black primaries. I saw him close enough to observe that his eyes were still dark.

  One of the female chicks from this nest was found, presumed dead, 65 kilometres north-east in the Moorfoot Hills on 14 November 1962. So, of the first nine I ringed, two were recovered, but this one had at least survived long enough to breed, once, or possibly twice.

  In the autumn of 1960, there was a vole ‘plague’ in some of the local young conifer plantations, and for the first time I saw Hen Harriers obviously hunting voles, accompanied by exceptional numbers of Short-eared Owls and Kestrels. On 26 September, two grey males and a ringtail were hunting a grass slope beside a young forest, and one male was seen to catch three voles in twenty minutes. Throughout the late autumn and winter, Hen Harrier sightings were more frequent and widespread than in any previous year; and although no full counts were made at the site of the winter roost a few birds were seen entering or leaving it. In July 1960, George Waterston had ringed three dozen chicks in Kintyre and recoveries, from this and subsequent ringing there, were widely scattered, though none were actually in Galloway.