Survey of Mew and Lighthouse Islands (Copeland group) in 1941


by Kenneth Williamson, Denis Rankin, Nial Rankin and H C Jones.


Contents:

 I Introduction
 IIAims of the visit
 IIISurvey of the Terneries
    a) distribution of the terns
    b) numbers of terns
  IV Systematic list of birds observed, including special notes on the Common Gull,
   Roseate Tern, a Whiskered Tern, and the Manx Shearwater colony.
 VBird-ringing summary
 VIEntomological notes

I        Introduction

It is good to visit an island uninhabited except by rabbits and by birds, an isle where your arrival is watched by a pair of Atlantic Seals who raise their large grey heads in curiosity from the still offshore sea, and – always a promising sign – an where the first to greet you are the rowdy oyster-catchers whose chicks lurk in hiding on the rocks close to the landing steps.

Such islands have a charm that is all their own, a charm that is linked with their isolation, their unspoilt wealth of vegetation, and the sanctity they afford to the creatures which make the island their realm. For the enjoyment of that atmosphere alone are they worth-while visiting; for that very reason do they attract men and women who love the open-air life.

The following is an account of a visit to Mew and Lighthouse Islands, off the larger Copeland Island and standing at the southern entrance to Belfast Lough. The party consisted of MN and DH Rankin, HC Jones and K Williamson. The stay was from 10.00 hours on the 28th June 1941 to 18.00 hours on the following day.

Headquarters were established in the old Lighthouse buildings on the island of that name, and a rowing boat was hired for the period to enable the party to work the Mew Island ternery in the morning and early afternoon of both days. It had been hoped to reach the island on the evening of the 27th and thus spend two full nights studying the status of the shearwater on Lighthouse Island, but owing to Police objection it was not possible to leave Donaghadee until the following morning.

II        Aims of the visit

The aims of the visit were to ascertain approximately the breeding strength of the various terns, in particular the rare Roseate Tern, and to ascertain the status of the Manx Shearwater, Eider Duck and common Gull. The expedition was largely successful in accomplishing these aims, with the exception that no luck was had with either of two of the breeding ducks Eider and Red-breasted Merganser.

It was hoped also to do some entomological work, but it quickly became apparent that the birds would occupy almost the whole of the available time, and such insects as were noted or were captured were done so incidentally to the bird work.

Eighty-five birds were ringed, including an adult Stock Dove and an adult Manx Shearwater taken from their burrows, as well as the highly satisfactory total of 55 young Roseate Terns.

III        Survey of the Terneries

Work on the terns was largely confined to Mew Island, only a cursory survey being made on Lighthouse – more in order to ascertain what species were represented rather than to arrive at any estimate of the numbers present.

Mew Island The bestview of the terns of Mew is undoubtedly that which is to be obtained from the partially demolished Lighthouse tower on the summit of the island of that name. The tower has been left standing at the height of the first platform, and as ground level at this point is shown on the O.S. 6” map as 96 feet, this most excellent observation post cannot be less than 120 feet. Looking out over the narrow sound one sees the low island of Mew, which at its highest point is only 32 feet above sea-level, extended map-like, the high tide filling the channels which actually split up the greater island into eleven sections.

The sight from the lighthouse platform was a bewildering one, as we gazed across to Mew shortly after our arrival. The sky was flecked with the white dappling of, it seemed, tens of thousands of milling terns. Our first feeling was one of utter amazement at the immensity of this great, humming life-centre of sea-birds, - our next, a feeling of defeat, for although one of our missions was to make a reasonably accurate estimate of the number of terns breeding on these two stations, that seemed to be well-nigh impossible in face of the huge numbers which confronted our eyes.

We were still convinced of the impossibility of this task when we landed on Mew about 11 o'clock on the Saturday morning, and during our circuit of the island we made no attempt at a population estimate. We did, however, note two things that were later of value in this connection, a) the comparative numbers of breeding birds on the separate islets of Mew, and b) the general distribution and comparative numbers of the various species.

IIIa        Distribution of the terns

A landing was made on section H, whence we passed to A, B, C, D, E, D again, and along the north-west coast of that section to F and G, and so back to H, where we embarked about 1530 hours for our own island across the strait.

Mew IslandThe southern part of H, and the whole of A, we found to be occupied almost exclusively by Arctic Terns, but this appears to be the only area on either of the two islands which is monopolised by this species. The Arctic Terns occur in fair numbers on B, C (on the southern corner of which it may outnumber Common), part of the east coast of D and the west an north-western side of H, but at these stations the Common Tern is in each case the more dominant of the two.

So far as we were able to ascertain on this first visit the Common Tern occurs abundantly on C, is present on E, and is the only tern breeding on the north-western and western sides of D. The nests are so close together on F that the section must be absolutely full to the capacity, whilst on G and H the Common occurs less thickly. The Common is easily the predominant species on Lighthouse Island, where it occurs in numbers within the area on the western side indicated by the dotted lines.

The main Sandwich Ternery is situated on D, at the south-eastern end, although two very small groups were found on C. It was not possible to ascertain the numbers as the young on D were well grown and the cover there – for this portion of the island is thickly clothed with bracken – provided an excellent retreat for the birds. One Sandwich Terns nest was located on the north-west coast of Lighthouse Island. It seems likely from the observations made, however, that the Sandwich Tern is the least common of the species on the two islands.

One of the chief aims of the expedition was to ascertain in what strength the Roseate Tern, which had been noticed there by Arnold Benington I 1940, and this part of our mission achieved a further degree of success than any of us had been optimistic enough to hope for. In view of the rarity of this interesting species, it is made the subject of a special note under the specific headings below.

IIIb        Numbers of terns

By Sunday morning the party, having recovered from the dazzling affect of the first encounter with the great colony, was inured once more with the desire to adopt some scheme which would provide a fairly reliable estimate of the number of terns breeding on Mew Island. Accordingly it was decided to make a count of a sample area, and the whole of the islet marked C was taken for this purpose. It was hoped, if sufficient time remained, to count also the Arctic colony on H-A-B, but unfortunately time did not allow.

This area C was chosen partly because the tern density appeared to be a fairly average one, and also because there was added interest in that the area included a small number of Sandwich Terns and the main colony of Roseates.

The whole of area C was carefully covered, the watchers moving four abreast, and DHR acting as recorder. Work was slow and somewhat laborious, especially in those areas where sorrel grew thickly and provided good cover for what few nests were situated in such ground, but the count was complete after 2.75 hours.

Nests totalled for all species: the margin of error (due to the presence of overlooked nests in the sorrel or juncos beds) was very small, and 1400, postulating 2800 breeding birds, would represent a very accurate estimate of the numbers present. The nests counted we allocated as follows though here again a small margin of error doubtless exists in that certain nests, recorded as those of Common or Arctic Terns, may conceivable have been those of the scarce Roseate (see under that species):

        Common and Arctic

Clutch size Number of nests  
8 1 See under Common Tern
6 1  
5 4  
4 1  
3 167  
2 702  
1 271  
Total 1147  

        Roseate Tern

Clutch size Number of nests
2 78
1 129
Total 207


        Sandwich Tern

Clutch size Number of nests
1 10
Total 10

        NB “Clutch” may be taken as including young birds.

From our observation of comparative density on other portions of the isle, we compute, using C as a sample, that the total tern population of Mew and Lighthouse is certainly not less than circa 8,700 breeding pairs.

Numbers of breeding terns on Copeland group
Mew Island C 2800
  D&E 1100
  D (NW side) 500
  F 3000
  G 2000
  H 1000
  A&B 2000
  Mew total 12400
Lighthouse Island   5000
Copeland Island   200
     
Grand total (for Copeland group)   17600



The Copeland Island ternery was not visited, and the above figure is a rough estimate based on the numbers seen as we sailed past the north and west coasts of the island on the Sunday evening. In actual fact only one colony exists on the western side, but scattered pairs were seen all the way round between the north and west coasts.

Density of breeding birds

Terns Common, Arctic, Roseate and Sandwich 20,000
Black-headed Gulls   500
Others Ringed Plovers, Rock Pipits and Oystercatchers 100
  Total 20,600

As the area is 26 acres, the average number of breeding birds per acre is circa 790.





IV        Systematic list of birds observed

During our visit a total of 38 species was observed either on or from the islands, and these observations are given in a specific list below.

Jackdaw:        Several pairs were seen on Lighthouse, sometimes flying near the eastern cliffs. In all likelihood breeding in old rabbit burrows though the sticks of an old nest were found below the chimney of one of the lighthouse buildings.

Starling:        A small party of juveniles was recorded on Lighthouse, and here a pair was also feeding young in a nest cavity under the ridge of the larger of the lighthouse buildings, and on the morning of the 28th a light blue eggshell which certainly appeared to belong to this species was picked up on the rocks of section C of Mew.

Linnet:        A few birds were seen on Lighthouse, once a party of five above the eastern slopes, and on other occasions three or four in the same vicinity. None of the birds seen appeared to be occupied with domestic affairs, but it is possible that the species breeds.

 Twite:        Four were watched [by] MNR and KW in the bushes of the field west of the lighthouse early on the 29th.
Prior to our departure from the landing an unidentified immature bird was flushed from the bracken near the landing, and was followed up for some minutes. There were warm brown edgings to the dark brown mantle and coverts, the breast was striated with dark brown, and the head and rump appeared to be a more uniform greyer brown. The bill was pale, inclining to straw colour, and the legs were flesh-brown. It shivered its wings slightly whilst perching, and the call when in was barely audible zee. It is just possible that it was a Twite.

Meadow Pipit:        This species possibly occurs, but owing to the lack of opportunity for a really close examination of suspected Meadow Pipits, it was never satisfactorily identified.

Rock Pipit:        The characteristic small bird of the two islands, occurring all round the coast and also seen much in the fields and on the heath of Lighthouse. At one time on 28th six birds were feeding together in the field below the Lighthouse buildings, and on another occasion a bird was disturbed from the garden. The only nest found was built among the rocks on Lighthouse Island in a typical position at the base of a patch of sorrel, and contained three eggs.

Whitethroat:        A close second to the Rock Pipit, and it is estimated that eight pairs were nesting on Lighthouse, four of them in the vicinity of the old buildings, where the males sang much from the elderberry bushes. The others occurred on the heath where there was good cover in the bracken and nettles and small elder shrubs, and there were two pairs quite near to the coastal rocks at the landing.

British Song Thrush:        2 pairs were present on Lighthouse, having their territory around the buildings among the thick growth of bracken, comfrey and elderberry. At 0440 hours on the morning of the 29th, when the party was retiring to the tents following a successful Shearwater hunt, the 2 males began heralding the new day with their beautiful voices.

One Song Thrush was seen wrack-feeding on Mew on the morning of the 29th.

Blackbird:        Several were seen on Lighthouse. There were certainly two pairs on Lighthouse. Single birds were disturbed several times on the eastern half of the island.

Swallow:        One spent some time hawking for insects around the lighthouse buildings on the afternoon of the 28th and again on the afternoon of the 29th. Some evidence of past or present nesting in the old buildings was sought but not found.

 Swift:        A party of four was seen from the Lighthouse tower on the 29th at 1430 (double summer time), moving with absolutely direct flight in an NE direction. They finally passed from view out at sea flying towards the Mull of Galloway.

Cormorant:        Odd birds were seen occasionally flying past the islands or fishing offshore. One was risen off the rocks on the east of Lighthouse Island on the evening of the 28th. Roosting with Shags.

 Shag:        More often seen than the last. On the evening of the 28th a party oof 32 gather in the sound between the two islands. All were immature.

Gannet:        An adult bird, and a brown immature specimen farther out, were seen off Mew on the 29th.

Common Shelduck:        Breeds in the burrows on both islands. Adults with one chick were seen swimming in the sound on the 28th, and later three unescorted young were watched near the landing place on Mew. Great pleasure was taken on 29th on finding six ducklings – whom we persuaded with difficulty to remain at home – crowding the entrance to their burrow in which was also an infertile egg. This nest was at a height of some 70 or 80 feet above sea-level and on the steep, bracken-clothed east slope of Lighthouse.

Eider Duck:        one of the disappointments of the visit was that we were unable to arrive at an idea of the breeding strength of the Eider Duck, whose first breeding place in Down was on this island. On 13/5/39 one nest was found on Lighthouse Island by DHR and in the following year A Benington noted two nests, saw three possibly four [pairs?] and believed all were nesting on Lighthouse island. We confidently expected an increase, but during our stay the Eider was only once seen, a female swimming in the sound with three ducklings on the morning of the 28th.

Red-breasted Merganser:        It was hoped to find the nest of this species, but we came across neither eggs nor young, though occasionally adult birds were seen in the sound. It had previously been estimated that four pairs bred on Mew and four on Lighthouse.

British Redshank:        Seen on the shores of both islands, but only once a small party, half-a-dozen coming under observation as we rowed back to Lighthouse from Mew on the 29th. A bird which we thought to be a juvenile, judging by the leg colour, was seen as we passed the Copeland Island on the 29th.

Common Snipe:        A common species on the heath of Lighthouse, and once seen on Mew. Usually rose in pairs, but on occasions single birds were seen rather anxiously running the gauntlet of the irate terns. Drumming was heard, in the daytime and at 0030 hours on the 29th, whilst later, at 0230, a bird was heard employing the Chip-pip-pip-call.

Common Curlew:        Did not come under observation until the small hours of the 29th, when a number of birds were calling about Lighthouse Island. On the Sunday a number was seen, including small flocks which rose from the heath. The largest flock was c.60 birds. All flew off towards the Copeland Island.

Ringed Plover:        Two nests were found in the Arctic ternery on Mew, one in section H on the 28th containing four eggs, and one on section A on the 29th containing one egg and two newly hatched young. Some fifteen yards from this site an active chick was taken and ringed but it is thought to have been to advanced to have belonged to the latter nest. Both parents were running with this bird when we approached. The Ringed Plover occurs on both islands, but its strength would difficult to estimate.

Lapwing:        Lighthouse must have a breeding strength of at least half-a-dozen pairs, nesting for the most part on the open land of the heath. A few young birds were seen on the wing, one half-grown chick was taken, and also two chicks of a newly hatched brood. Lapwings were often made the butt of the tern's temper when the nesting ground was approached. A few birds were seen flying over the fields of the Copeland Island, where the bird is more abundant than on Lighthouse. Some movement was noticed on the 29th. At 1400 hours a party of ten (which did not visit us) was observed flying towards the Mull of Galloway, in which direction they finally disappeared from sight. At 1600 hours there was a flock of twenty on the island, which flew in a northerly direction on leaving. At 1700 hours a party of six birds visited Lighthouse and went off to the north-east, finally passing from sight as the former party had done.

Oystercatcher:        A common bird on all three islands, especially Copeland. On Lighthouse five pairs were counted between the eastern cliffs and the rocks 100 yards to the west of the landing place, and four of these appeared from their noisy behaviour, to be shepherding young. Two well grown young were captured and ringed on a large rock off the eastern cliff by DHR on the 29th. Another pair almost in variably seen standing on the wall at the foot of the lighthouse field, must have bred on the heath.

Turnstone:        On landing at Lighthouse on the 28th two immature Turnstones were seen on the rocks, and these flew to join a passing party of three others. Subsequently small parties, the largest containing 14 birds, were seen on the Mew and Lighthouse coasts.

Common Gull:        One of the most satisfactory aspects of the weekend was the proof that breeding has occurred in the case of at least two pairs of Common Gull on Lighthouse, whilst there is very strong presumptive evidence of the breeding of not less than five pairs altogether. The first pair watched were rather pathetic in their anxiety for the nest, which, when found, was seen to contain three long-addled eggs. One bird of the pair (the female?) actually went so far as to make a few ineffective stoops at the discoverers. This nest was on the summit of a seven foot high rock beneath the eastern cliff, and although three birds were once seen in the air together above this site, it is believed that only one pair were together on the rocks above the coast immediately below the north-west corner of the lighthouse enclosure. All evinced anxiety whilst the party was in their immediate vicinity, although when we had passed on some little way the birds were content to stand on the stone wall. At this site HCJ caught a young chick, probably about two to three weeks old, and this was ringed.

Greater Black-backed Gull:        The solution of the mystery surrounding the status of this fine but undesirable bird is a job awaiting future visitors to Lighthouse Island, for the party feels confident , but have no proof that a pair are breeding just to the east of the Common Gulls. When their territory was approached the deep ow;ow;ow; of anxiety was easily to be heard above the racket of the terns on one hand and the gulls on the other.

A number of immature birdswere seen amongst the heterogeneous mixture of Herring Gulls resting on an offshore rock near the landing on the 28th, and odd birds, but only very occasionally mature specimens, were not infrequently observed. On our arrival at Lighthouse on the 28th a flock of 16 second-summer birds rose before on the heath near to the buildings. This is the greatest number seen together during the visit.

Black-headed Gull:        A fairly common breeding species on both island, but especially so on Mew, where the birds bred in numbers among the bracken and sorrel cover of section D. Most of the young were well grown and running about in the security of the cover, but nests with eggs and newly-hatched brown chicks were not uncommon, whilst a few youngsters were already on the wing. This was, in fact, the only gull whose young had reached such an advanced stage, and these various stages of growth together with the profuseness of the undergrowth, made anything like an accurate estimate of breeding numbers impossible. On Lighthouse the main population of Black-headed Gulls is centred along the shore between Black Rock and North Rock, where they breed among the Common and Arctic Terns.

Herring Gull:        A fair number breed below the north-east cliff slopes of Lighthouse, as far round to the north as the Common Gull's site and the beginning of the tern ground. One pair, nesting solitarily on the southern corner of the isle not far from the landing, had two youngsters and a third chipping the shell on the afternoon of the 28th.

Common Tern:        There is little to add to what has already been said about this the most abundant bird of the two islands. It was noted how many of chicks tend to be lighter, a more yellowish-brown, than those of the Arctic, although it is unsafe, of course, to adopt this as a factor establishing identity. A much better character is the wholly white down of the under-surface, in comparison to the dusky wash on the down of the ventral portion of the Arctic chick.

From the figures obtained in our survey of section D it is seen that the normal clutch is of two eggs. One clutch of six, one of four and four clutches of five eggs were found, this confirming the Rankins' previous experience that five is more common than a clutch of four. In cases of five and above it is almost certain that two were responsible, and it would be interesting to know it this was a sign of over-population, for the excessive clutches were all in the same area. In the case of the eight egg nest the bird was only incubating four, a fifth lay just outside the nesting-scoop, and the remaining three lay a few inches away.

Arctic Tern:        This splendid fearless bird could be seen to best advantage on section A and the adjacent part of H, where members of the party had much amusement at the expense of aggressive parents. A number of birds not only here but on other parts of the island, actually attacked intruders, but no hard blows were received. Usually the feet were dropped as the bird reached the end of its dive, but the general opinion is that the blows actually struck were glancing ones delive [sic] by the body. In the latter case the stoops were short ones, a swift dive down, a quick zoom upwards in an opposite line, succeeded by three or four wing beats which actually carried the birds backwards and enabled it by a deft side-slip to reach position once more for the initiation of another dive.

Dive-bombing was not uncommon during these displays and the target area more often than not suffered as a consequence. But at any time during one's stay in the ternery one might expect a hit from the scores of birds milling about above one's head.

The majority of the Arctic chicks were of the dark-brown form, and the grey phase was found to be extremely rare. All the tern chicks discovered, with the exception of the Sandwich, were in the down plumage, and only a very few indeed had parted with the egg-tooth. A count of 17 nests in the Arctic colony gave nine clutches or broods of one, and eight of two.

Sandwich Tern:        Little remains to be added to the foregoing notes on this species. It is much more local in Ireland than the Common or Arctic Terns and on Mew, where in 1939 some eighty breeding pairs were recorded, it is the laest common of all the terns. The majority of the bird bred either among or adjacent to the cover of the high growing bracken or sorrel on section D, and have as neighbours the Black-headed Gull. This colony was much advanced beyond the few small groups of Sandwich on section C, the young birds being fairly well feathered, whereas on C eggs only were found in shallow depressions on flat and much-whitened rocks. The only nest of this species found on Lighthouse was situated near a small sorrel plant, and on the opposite side, at about two inches radius, was a matted half-circle of excrement by the bird evacuating without leaving the nest.

Roseate Tern:        This beautiful bird provided one of the high-lights of the expedition, and first in point of view of satisfaction comes the success which our search for this species encountered.

Knowledge that we were first among the Roseate Terns came when one of the party caught the light of the delicately beautiful rosy tinge on the breast of a passing bird. Almost immediately afterwards a chick was found, and a search in the immediate neighbourhood revealed the fact that we were standing among a small colony of nests, which were, however, admixed with those of the Common Tern. This was the morning of the 28th. The full extent of the colony was not realised until a census was made of this section on the following day.

The size of the colony could not but give the greatest satisfaction in view of the precarious status of this species in Britain today. The minimum strength, which included 78 clutched or broods of two, and 129 single eggs or young. Was put at 207 breeding pairs: and then it is borne in mind that only the easily identifiable chicks and typical eggs of the species were counted, then it is clear that this figure represents an error on the low side which is probably not less than between 5 and 10 percent. The same may be said of the two other groups located, although in their case the error is less significant because the groups were very small. In each case the Roseate was found breeding in areas where the Common was the predominant bird, although the Arctic was present in small numbers.

The second group of Roseates, on section E, had probably not more than a dozen pairs, and at the third station, on the western corner of F, at least twice that number were present. Four of the nests there contained two eggs, one an egg and a chick, and a third pair had two young. The remaining 18 were 'singles'. Soon after we had retired from this site one of the party counted 22 Roseate Terns on the site, and there must have been others hidden by the rocks.

The chick of the Roseate is very distinctive – a darker and duller brown than that of the Common or Arctic chick, and remarkably consistent in the colouring of the down plumage. The down and the colour of the legs are both diagnostic characters – the former has a distinctly spiny appearance in contrast to the fluffiness to the down of the Common [and] Arctic chicks, and this is observable even when the youngster is only partly dry following its escape from the egg. The legs are almost the same colour as those of the young Black-headed Gull, a dark purplish-brown, and although in young the colour is much paler, - indeed, almost flesh when hatching it at no time approaches the bright flesh-pink of the legs of the young of other medium sized terns. The irides were noted as dark brown, and the bill dark brown at the base and for nearly half its length from the tip, but flesh-pink in the medial portion.

The eggs, unless of the unmistakable typical form, are not nearly so easy to distinguish, and it is certain that in the count a number were passed over as those of the neighbouring species. One chick, for instance, was ringed soon after emergence from an egg of oval shape which had a dark brown belt almost encircling the middle. Another not dissimilar egg, suspiciously like a Common Tern's, was seen lying alongside a typical Roseate Tern's egg in another nest.

In its characteristic form the egg of the Roseate is longer than that of the Common or Arctic, and is markedly pyriform in shape: the ground is usually a shade of light brown or buffish, and is closely spotted and flecked with darker brown, grey, sepia and black, the distribution of the spots covering the whole surface but being grouped most thickly at the larger end. The size of the spots varies but blotching is very rare. 55 young Roseate Terns were ringed by the party, and had out trip taken place a week later it is likely that four times that number would have been marked.

In the adult the best and surest means of identification is the polished black bill – even at the short distance of twenty yards the small area of red at the base of the bill could only be made out with some difficulty and only by using glasses. The delicate, almost evanescent roseate tinge on the under-parts was a feature of striking beauty when seen, but unfortunately its splendour depends on the incidence of a good light from a sympathetic angle. It was seen to best advantage, although fleetingly, when a bird turned inwards during its flight above the colony, and occasionally we admired the rosey flush on resting birds as they turned towards us, facing the sun. more often than not, however, there was no vestige of this feature from which the wholly delightful species derives its common name.

The encounter with the Roseate Terns was an inspiring one the memory of which will live a long, long time. To it that party must feel that a large measure of the unparalleled success of the weekend's birding was due. One cannot but deplore the conditions and activities of acquisitive men, which have decreed that so magnificent a creature as this shall be one of the scarcest of British birds, - conditions which make it eminently desirable that the status and distribution of the Roseate Tern should be shrouded in the utmost secrecy.

Black Tern:        Whilst we were outlying Arctic Terns on the edge of section C on the morning of the 28th an extremely dark tern was seen flying fairly low in company with other terns. MNR, DHR and HCJ had the first and best views of the bird, and noted particularly a striking white vent and a well marked black cap. The underparts were blackish, wings and mantle grey, the former appearing lighter towards the tips. When KW first saw the bird it had risen to a considerable height and offered no details of plumage to the eye. In comparison to the terns near the most outstanding detail was the 'square' tip on the tail, there being no vestige of streamers or of a definite fork. It was clearly noted that the strange bird was of similar to the Common and Arctic Terns, although the effect of the squared tail was to make the body look somewhat shorter.

The bird rose to a height of 500 feet, flying strongly with the primaries set back at an angle of 45 degrees to the forearm. Once it descended in a series of swoops to a lower level, but almost immediately began climbing again. We watched the bird until it was a mere speck in the glasses off the north-eastern corner of Mew.

HF Witherby made the suggestion that the bird may have been a female Black Tern in breeding plumage, in which there is a fairly well marked black cap.

British Razorbill:        A few birds were occasionally seen passing off the shores of one or other of the two islands.

Black Guillemot:        The first Tysties seen comprised a party of four flying out from Copeland Island as we approached our destination on the morning of 28th. When we had installed our kit in the old lighthouse and had climbed to the tower for a preliminary survey of our surroundings we saw another party of the same number in the sound between the two smaller islands. Black Guillemots, probably two or three pairs, were undoubtedly breeding on Lighthouse, for on every occasion when the northern coast of the isle was visited three or four tysties were seen swimming offshore with sandeels dangling from their red beaks, as though content to wait all day for us to pass on before coming in to feed their young.

Manx Shearwater:        The Manx Shearwater was first recorded as a breeding species fo Co Down on the strength of a bird taken from an egg in a burrow on the north side of Lighthouse by C D Deane and MNR in 1939 (Irish Naturalist's Journal, vol. p. ) and one of the chief aims of the visit was to determine the approximate strength and distribution of the colony if possible.

Shearwaters were first seen flying off the south-western shore at 2120 hours on the 28th, and subsequently other small parties were seen about the island coast. For some time there had been every promise of a perfect Shearwater night. It had been a grand clear day, - so clear, that the Calf of Man, the Shearwater's classical home, had been visible fifty miles away to the southeast. During the evening, however, fleecy white clouds enveloped the coast of Antrim, rising and massing above the real hills like hills of snow and ice. The clouds spread, and soon encroached on Copeland and mainland beyond, and soon the upper portion of the tower of the lighthouse on Mew was hidden also. Then the foghorn began its hideous, quadruple moaning blast which went on throughout the whole night, and, with the frequent blasts from ship's sirens, mingled with the never resting terns as they milled in dark silhouettes against the mist-wreathed sky. The noise that night, on every part of the island, was dreadful: it had to be experienced to be believed possible.

After an hour's entomology in the fading light we turned in for another hour's rest, and shortly after two went forth into the night to see what luck these halcyon Shearwater conditions would bring us. First we visited the northern gulley on whose slopes the first Down Shearwater was taken two years ago, and we sat there quietly waiting. The unceasing grievances of the terns rang in our ears, and now and again the deep bass of the Greater Black-backs could be heard above, and to the east a little way the Herring Gulls mixed their tempo with the tern's, while the sad plaints of a pair of Common Gulls could be heard. Only once in a while was there silence for a few seconds, - when the periodic 'dread' settled over the great flock-mind of terns, and the only sound was that of a thousand wings, and the inefficacious voices of a few dissenters who somehow tried to avoid being caught up in the astonishing wave of quietness and of fast fleeting peace.

From all these sounds we tried to dissociate our interest, keenly attuning our ears for the call we hoped would come, and the voice which alone could give us the information we were there to seek. And suddenly, it was there – one bird's voice impinging on the voices of a thousand other, travelling to us clearly out of the cloak of darkness and wraith-like mist. It was the hurried cuc-cuc-quark-cuc of the Manx Shearwater, a call which has been variously represented, but which nevertheless is quite easily distinguishable from the calls of all other birds. A moment later one bird swept overhead so low and so ghost-like that we must all have involuntarily ducked our heads.

Within a few minutes other birds were heard, some as they flew over the field below the Lighthouse enclosure, or were seen as fast moving shades as they cleared the stone wall and swept over the gulley. Soon another voice was located (this burrow we marked down for examination on the morrow) this time rather muffled and obviously near at hand, we traced it to the interior of a burrow on the top of the western slope.

From this portion of the island we crossed to the landing on the south side, near which a promising area had been located during a reconnaissance on the previous day. Here there was certainly more activity, and several burrows near the top of a coastal knoll were occupied. Birds flew overhead, calling, at frequent intervals, and once a scuttering on the ground quite close to us marked the run of a bird just taking off. Unfortunately we were just too late on the spot to effect a capture: however, a few minutes later a bird was taken following a short chase over the rocks and through a painful nettle-bed, and the captive examined closely before being ringed and released. During the whole time she was in the hand the eyes were tightly closed, exposing the white feature of the eyelids, and it seemed as though even the dim light outside was too strong for the bird immediately following her long period (at least one full day and possibly more) on the nest. The beak and claws were strong and sharp, as those who handled her were made well aware. On being released she stumbled along over the ground, unable to rise, but when finally left to herself was near enough to the sea to get away without much more difficulty.

Meanwhile other birds were calling from further inland from time to time, some fairly close at hand, and a few quite clearly calling as they taxied across the rough ground emerging from their burrows. The majority of the inland cries were in the general direction of a much burrowed bank which runs across the middle portion of the island above the limit of the tern ground, and it is thought likely that a good many of those holes are the homes of Manx Shearwaters. In all probability the birds range along the western side between the two points we examined, but are more in number towards the southwest than on the northern side.

It is difficult to say from one night's watching – a period of about ninety minutes – how big the colony is, but the general impression is that it cannot be less than 50 breeding pairs, and if the distribution in any way approximates to the one suggested, may well be nearly twice that number. The last Shearwater call was heard at 3.10 am.

There remains to add, as a postscript, that we dug the marked north-side burrow in the fierce heat of the following afternoon. We sank four shafts in the hard, stoney soil, a job which took nearly ninety minutes of our valuable time, only to find that the tunnel eventually emerged at another hole nine feet or so from the first. There was neither bird nor egg in it, - nothing for our toil but a mass of broken sorrel stems, a few white breast feathers, a rabbit's skull and lower jaw, and some aged bones and an aged skull of one of the Lighthouse Shearwaters of long ago.

Even that was not a negative result. The brown skull, coracoid, metatarsus and other disinterred bones probably put the age of this the first Co Down colony at one or two decades at least.

Moorhen:        Two nests were found on Lighthouse, each containing four eggs. One was half-way down a steep coastal gulley on the north-eastern side, and the other was in a high and thickly matted bed of juncos on top of the isla.

Stock Dove:        From the numbers seen at one time or another it is probable that about half-a-dozen pairs breed on Lighthouse Island. In a large gulley on the east side there were at least two occupied burrows, and the sitting bird was taken from one of these and ringed. The bird unfortunately escaped from the second. Both burrows were badly fouled and as no egg or young were within reach, it is not certain whether the birds were breeding or roosting there. A bird was risen from this spot every time the area was visited. The first Stock Doves seen, a pair, were watched evading the stooping terns on the edge of the sea-bird's colony on the western side. As many as seven birds were seen together on one occasion.





[The copy of this report that is held by the CBO finishes at this point. We would be interested in receiving a copy of the remainder of the report should anyone have it – please contact Shane Wolsey: shane@swolsey.biz]

© Copeland Bird Observatory, 2001 – 2004

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