Notes on the natural history of the Bell Rock

by J. M. Campbell

SEPTEMBER 1901.

The Rock has taken on quite a wintry appearance. The vegetation on the more exposed portions has entirely disappeared under the influence of the heavy seas experienced during the greater part of this month. The acorn barnacles with which the higher parts were encrusted are following suit owing to the ravages of the white whelk; the terns have deserted us, and, to complete the prospect, on the morning of the 19th we had the first visit of our winter boarders, the eider duck. A chip of rock covered with acorn barnacles becomes an interesting object when placed in the aquarium. Each conical shell is packed as close as possible to its neighbour, apex upwards. The apex is open, and fitted with a lid composed of four shells. Under water these lid-shells are seen to separate, and a bunch of “fingers” set on a stalk are thrust out, make a clutch, and are withdrawn. The “fingers” have extremely fine hair-like processes fixed at right angles to them, the whole forming a sort of net through which the water is filtered and the minute food-forms retained. It is interesting to know that although now fixed immovably to the rock these animals began life as free swimmers, and, strange to say, closely resembled the young crab. Another object we had under observation at the same time was one of the sea anemones, named the dahlia wartlet. A fleshy-looking disc studded with pieces of broken shell and sand, it appeared anything but attractive; but seen in the aquarium, the connection with its floral namesake was at once apparent. Unfolding itself from an orifice in the centre, as one would “flype” a stocking, rows of beautiful coloured tentacles were disclosed. These tentacles have the property of adhering to any object they come in contact with, and contain within themselves some wonderful mechanism. Placing a fly on the extremity of one of the tentacles, it was immediately held fast. The whole of the tentacles then curled inwards, carrying the fly with them, thus clearly showing their function.

The heavy easterly surf has deprived us for the present of our fishing, forcing the fish off the rock to deeper water. There are evidently plenty about, as the gannets are to be seen busy diving in the vicinity. It is extremely interesting to watch these birds pursuing their prey. Flitting near the surface, they enter the water at an angle of about twenty degrees; again, at a higher altitude, they drop like a plummet, describing an arc of bubbling foam from their entrance to where they emerge with a bounce a few feet further ahead, beating the water with their wings for several yards before being again fairly on the wing. The air cells pervading various parts of the body of a bird, and which contribute to its buoyancy, are probably vested in a greater degree in the gannet, an extremely large one being situated in front of the forked bone, or clavicles. Several instances are recorded where a bird which had its windpipe temporarily obstructed was able, by means of these cells, to carry on the function of respiration through the wing bone, the broken end of which protruded through the skin. The voluntary compression of these cells, by expelling the air, destroys the buoyancy of the bird, and explains the amazing rapidity of its descent. An objectionable method is practised in some places for the capture of these birds. A submerged piece of planking with a herring fixed to its upper surface is set adrift, or towed from a boat, in the vicinity of their fishing grounds. Swooping from an altitude, say, of a hundred feet, they apparently see but the herring alone, with the result that their necks are dislocated by impact with the plank, the impetus of their descent being sometimes so great as to bury their bills to the base in the wood. It is a common sight here, during the breeding season, to see these birds trooping past in Indian file to their home on the Bass Rock, in batches of a dozen or so, each preserving a regular distance from his neighbour. Though I have frequently watched them pursuing their vocation, I have never seen them bring their prey to the surface, nor could I say whether their dive was successful or not; but occasionally they emerge from their dive with a satisfied “honk,” which may be translated “got ’im.” Gifted with an insatiable appetite, they sometimes gorge themselves to such an extent as to be incapable of rising from the water, when they may be easily captured, as they make no attempt to dive. An instance of this was witnessed by a large crowd one Sunday, a few summers ago, in Arbroath Harbour. Some conception of the carrying capacity of these birds may be had when it is known that a sitting mother bird has been seen to insert her bill into the inviting mouth of her returned partner and deftly extract, one by one, as many as six full-grown herring.

A “false alarm” was occasioned at the end of last month by two cormorants or scarts appropriating the signal poles as a roosting-place. One of these poles is fixed on either side of the balcony, and projects horizontally. When a signal is made from the Rock, two-feet discs are suspended from them in pre-arranged positions. A wire stay from the balcony railing supports the extremity of each pole, and on this stay the birds were seated, one at the outer end, the other in the middle. Discs in this position, but pendant from the pole, by our code reads “Send boat,” and this the keeper on shore duty in Arbroath construed it to be and acted accordingly, with the result that we were somewhat alarmed by the appearance of the harbour tug about eleven the same evening. Our impression was that something serious had happened on shore, and that one of our number was urgently wanted. On the tug hailing us, and saying they had been sent out in response to signals shown from the Rock that afternoon, our minds reverted to the birds, and our fears set at rest. Considerable alarm prevailed amongst our families, and not until the tug returned with the news that “All was well on the Rock” were their fears allayed.

On the morning of the 27th the sea round the Rock was seen to be strewn with apples, a few dozen of which we managed to secure. Their presence here is a mystery, and we trust has no connection with the long spell of fog we have had. On the 24th we completed a fusillade of forty hours, a record run of fog.

October 1901.

OCTOBER 1901.

The flock of eider ducks which keep us company through the winter increases daily, and now numbers over thirty. Swimming and diving amongst the breakers from daylight till dark, it is astonishing how they escape being smashed on the bare rocks. The receding wave may leave them almost stranded, and just as the incoming breaker is about to engulf them, they pop through its base and come up on the other side in a smother of foam. They are sometimes quite close to the tower, and then we have an interesting view of their proceedings. The diving of one is generally the signal for the remainder to follow, and the whole flock may be clearly seen, a couple of fathoms down, scurrying over the rocks in eager quest of the different dainties on their menu, consisting chiefly of small crabs. The capture of one of these crabs by no means ensures that it will ultimately contribute to the duck’s sustenance—this is not intended as a reflection on their digestive power, which appears equal to anything short of nails, considering the quantity of hard-shelled crabs they assimilate during a day’s fishing—for, on gaining the surface with his prize, he may be immediately assailed by the marauding gulls and compelled to dive with his prey. This may be repeated several times, until he reluctantly surrenders the succulent tit-bit, or is compelled to swallow it under water—a proceeding they are evidently averse to, otherwise the gulls would fare but poorly in their nefarious calling. The uncertainty of the crab’s final lodgment is again demonstrated in the case of the successful “blackmailer.” Hastily swallowing his booty to avoid being plundered in turn by his fellows, he is again on watch for the reappearance of his unwilling providers. But retribution occasionally overtakes the despoiler as it does his human prototype, with the difference that in default of imprisonment, he is mulcted in the contents of his stomach, the nemesis in this case being the dusky-coated skua or robber gull, who with his hawk-like flight easily heads him at every turn, and the chase terminates only when the contents of the stomach are disgorged, or the excrement voided, either of which is adroitly caught by this foul freebooter of the sea before it reaches the water.

A hazy moonless night, with a sou’-easterly breeze and drizzling rain—given these conditions, at this season of the year we have numerous visits of various birds, members of the autumnal migratory flight. Making straight for the light, they dash themselves against the heavy plate-glass of the lantern; many of them are thus killed and swept by the wind into the sea. Others, again, arrive with more caution, and though taken in the hand and thrown clear of the tower invariably return, and remain fluttering against the glass till daylight reveals to them the futility of their exertions in that direction. The most numerous of these visitors are the redwings and fieldfares, but blackbirds, larks, starlings, wheatears, finches, tits, etc., may be met with in the course of the season. It is somewhat startling, when on watch in the lightroom, to hear the thud with which they strike. The woodcock, owing to his rapid flight, strikes hardest of all, and the other extreme is met with in the smallest of our British birds, the tiny gold-crested wren, whose presence on the lantern is announced by a feeble tinkling sound, which a robust butterfly might easily imitate. The heavier birds do not always strike with impunity; instances have occurred where ducks have gone clean through the lantern to the derangement of the revolving gear of the light, the splintered glass bringing the machinery to a dead stop. An incident of this nature happened a few years ago at Turnberry Lighthouse, on the Ayrshire coast, the intruder in this case being a curlew or whaup. A storm-pane is considered a necessary adjunct to every lightroom, and is always held in readiness to be shipped in case of such emergency. At some shore stations it is customary on the approach of a favourable night, during the migratory period, to keep the cats indoors to prevent them mangling the expected catch. In one particular instance the birds collected of a morning filled an ordinary clothes-basket, and a few nights later included five wild geese, which were secured out of a large flock that came to grief on the dome.

An hour before daybreak on the 22nd it appeared as if we were about to suffer a bombardment, and that daylight was to witness the commencement of hostilities. No less than seven torpedo-boat destroyers were seen creeping close up to the Rock, their low black hulls scarcely discernible in the feeble light, and not until daylight disclosed the white ensign were we assured of their intentions. A little later they were joined by three gunboats and, after some clever manœuvring, formed into three lines, the gunboats occupying the centre. They then steamed away in the direction of the Firth of Forth. Two hours later other three gunboats passed us, going in the same direction, escorted by four destroyers, and followed shortly after by a solitary gunboat. Extremely interesting it was to witness the precision and dexterity of their movements as they swung into their respective positions for the advance, their semaphores all the while going like windmills. Again, on the 24th, about 11 a.m., a fleet of about a dozen battleships, headed by a dispatch boat, was seen moving in stately procession from the Tay, evidently bound for the Forth.