near the nest, is ready to guard it from all intrusion. Should another
bird fly on to the rock and alight, in his opinion, too near it, he
immediately advances towards him, shaking his wings, and uttering a low
grunting note which is full of intention. Finding itself in a false
position, the intruding bird flies off; but it sometimes happens that
when two nests are not far apart, the sentinels belonging to each are
in too close a proximity and begin to cast jealous glances upon one
another. In such a case neither bird can retreat without some loss of
dignity, and, as a result, there is a fight.
I have witnessed a drama of this nature. The two locked their beaks
together, and the one which seemed to be the stronger endeavoured with
all his might to pull the other towards him, which the weaker bird, on
his part, resisted as desperately, using his wings both as opposing props
and to push back with. This lasted for some while, but the pulling bird
was unable to drag the other up the steeply-sloping rock, and finally
lost his hold. Instead of trying to regain it, he turned and shuffled
excitedly to the nest; and when he reached it, the bird sitting there
stretched out her neck towards him, and opened and shut her beak several
times in quick succession. It was as if he had said to her, “I hope you
observed my prowess. Was it well done?” and she had replied, “I should
think I did observe it. It was indeed well done.” On the worsted bird’s
ascending the rock to get to his nest, the victorious one ran, or rather
waddled, at him, putting him to a short flight up it. This bird was also
cordially received by his own partner, who threw up her head and opened
her bill at him in the same way, as though sympathizing, and saying,
“Don’t mind him; he’s rude.” In such affairs, either bird is safe as soon
as he gets within close distance of his own nest; for it would be against
all precedent, and something monstrous, that he should be followed beyond
a charmed line drawn around it.
EDMUND SELOUS. (_From “Bird Watching” and “The Bird-Watcher
in the Shetlands.” J. M. Dent and Co. By permission._)
THE BIRDS OF SULE SKERRY.
Sule Skerry is a tiny, barren, surf-bleached islet, lying far out in the
open ocean, thirty-two miles west from Hoy Head, about the same distance
from Cape Wrath, and thirty miles from the nearest land, Farrid Head,
in Sutherlandshire. The Skerry, roughly rhomboidal in outline, is about
half a mile in length and a quarter of a mile in its greatest width, and
attains a height of only forty-five feet in its central part. All round
the shore is a belt of bare, jagged rock, where the wash of the great
Atlantic waves prevents any vegetation from finding a foothold, and of
the thirty-five acres or so which form the entire area of the island only
some twelve are covered with a mossy, vegetable soil.
Lying, as it does, right in the track of trading vessels, this low
islet, together with the Stack, which rises to a height of more than a
hundred feet some four and a half miles to the south-westward, formed
a death-trap to many a ship, which was, no doubt, afterwards merely
reported as “missing,” and its shores when visited were rarely found
without some stranded wreckage to tell of the unrecorded tragedies of
the winter seas. It was not till the year 1892 that steps were taken to
mark this dangerous rock, but three years later saw the completion of
Sule Skerry Lighthouse, a massive tower of a hundred feet in height, with
a powerful light visible for a distance of eighteen miles.
Sule Skerry is no longer either a dangerous or a lonely islet when
compared with its former state. The three lightkeepers who are always
on duty, together with their goats, poultry, and rabbits, give quite
an inhabited air to the place—probably too much so for the comfort of
the original occupants, the flocks of birds which find on it either
a permanent home or a temporary dwelling-place. Sule Skerry is an
ideal place for observation of the birds which frequent our islands,
both from the immense numbers of them which nest there, and from the
absence of high cliffs or inaccessible rocks. Luckily for us, one of the
lightkeepers formerly on this station, Mr. Tomison, a native of Orkney,
was a man unusually well qualified for such observation, and he has
recorded much that is of interest regarding the bird life of the Skerry.
From one of his papers on this subject we quote the following interesting
pages.
[Illustration: _Sule Skerry Lighthouse._]
The Residenters.
The birds of Sule Skerry may be divided into three classes—the
residenters, the regular visitors, and the occasional visitors. The class
of residenters is represented by the great black-backed gull, the herring
gull, the shag or green cormorant, and the meadow pipit.
[Illustration: _Great black-backed gull._]
The great black-backed gull is one of the handsomest birds of the gull
family, but owing to its destructive propensities amongst small birds,
rabbits, and occasionally young lambs, a continual warfare has been
waged against it for years by farmers and gamekeepers, until now it is
almost entirely banished to the outlying parts of the country. Before
the lighthouse was erected on Sule Skerry, large numbers of this species
frequented the island; but the lightkeepers found them such arrant
thieves that they reduced their numbers considerably. There are still
about twenty pairs resident on the island all the year round, and they
seem to find plenty of food either on land or at sea. Their breeding-time
is in May, and sometimes as late as June. When the young are hatched the
parents are continually on the lookout for food, and I have often seen
them swoop down and seize young rabbits. Frequently they make desperate
efforts to capture the old rabbits, but never successfully. They lay
three eggs in a nest composed of withered grass, and the process of
incubation lasts about four weeks.
[Illustration: _Herring gull._]
A small colony of herring gulls stays on the island all the year round,
but in summer vast flocks of them are in evidence when the herrings are
on the coast. Only the residents remain to breed, and about a dozen
pairs annually rear their young and spend their whole time in the
vicinity. Some of the young must emigrate to a more genial climate, for
although rarely disturbed their numbers are not increasing. They lay
three eggs early in May, and sit about four weeks. When hatched, the
young immediately leave the nest, and are so like the surrounding rocks
in colour that when they lie close it is almost impossible to discover
them. When hunting for food for their offspring, these gulls are almost
as great a pest as their cousins, the great black-backed, and are more
audacious thieves.
The most numerous of the residenters are the scarfs. In summer and winter
they are always on the island, and apparently there is an abundant supply
of suitable food in the vicinity, for they never go far away. During
winter they congregate on the rocks in large flocks or colonies, and they
have become so accustomed to man’s presence that they fly only when one
approaches within a few yards of them. In very stormy weather they seek
refuge in some sheltered spot, far enough away from the coast-line to
be safe from the encroaching waves, and only when frightened by any one
approaching too near do they choose what is, in their opinion, the lesser
of two evils, and seek safety in flight. With the advent of spring they,
like all other birds, turn their thoughts to love. Their comparatively
homely winter dress gradually changes to one more appropriate to this
sentiment and more in harmony with the imposing surroundings. Early in
the year their plumage assumes a greener tint, and the graceful tuft
or crest on the top of the head becomes more and more prominent. This
crest practically disappears about the end of June, and seems to be a
decoration in both sexes only during the nuptial season. Usually they
manage to get through with their love-making and selecting of partners
by the middle of March, after which the operations of nest-building are
undertaken.
In Orkney we associate a scarf’s nest with some almost inaccessible
cliff, but such is not the case on Sule Skerry, for the simple reason
that there are no cliffs. The nests are built all over the island, but
principally near the coast-line; and the sociableness of the bird’s
disposition shows itself in this fact, that they tend to crowd their
nests together in certain selected spots, to which they return year after
year. One place in particular, a patch of rough, rocky ground from forty
to fifty yards square, I have named the scarf colony on account of its
numerous population during the breeding season. Here in 1898 I counted
fifty-six nests.
As to the materials used for nest-building, these are principally seaweed
and grass, but the scarf is not very particular as to details, and uses
anything that will suit the purpose. I have found pieces of ordinary
rope, even wire rope, and small pieces of wood used, and a very common
foundation is the skeleton of a rabbit which has died during the winter.
During building operations I have observed that one bird builds and the
other brings the materials. After all has been completed, three, four,
and sometimes five eggs are laid. Three is the most common number; five
is rare. During incubation the one bird relieves the other periodically.
It is a common sight to see one come in from the sea, sit down at the
edge of the nest, and hold a long palaver with its mate. The sitting bird
then gets up and flies out to sea, the other taking its place.
When the young come out of the egg they are entirely naked, of a dark
sooty colour, and particularly ugly. Towards the end of the first week of
their existence a coating of down begins to grow, followed by feathers in
about three weeks. As near as I can judge from observation, the bird is
fully fledged in five weeks from the time of hatching.
[Illustration: _Meadow-pipit._]
The only other residenter is the meadow-pipit, tit-lark, or moss-cheeper.
It is the only small bird that remains on the island all the year round.
It nests generally in May, and lays five or six eggs. It is said that
two broods are raised in the season, but I have never noticed that here.
Towards the end of summer they are to be seen in considerable numbers,
but in September and October the island is visited by kestrels, who soon
thin them down.
The Regular Visitors.
The regular visitors are puffin, razor-bill, common guillemot, black
guillemot, oyster-catcher, tern, eider duck, kittiwake, stormy petrel,
curlew, snipe, turnstone, and sandpiper. In this list I have advisedly
placed first the puffin, or tammynorie, or bottlenose, or coulterneb,
or pope, or sea-parrot, for it is a well-known and well-named bird. In
point of interest it undoubtedly takes the first place among all our
feathered friends. Its remarkable appearance, its activity, its assertive
disposition, and the regularity of its habits, compel the attention of
the most careless observer.
[Illustration: _Puffin._]
At one time puffins were much in demand for food. An old history of the
Scilly Islands tells us that in 1345 the rent of these islands was three
hundred puffins. In 1848, on account of the bird having got scarcer, and
consequently more valuable, the rent was fifty puffins. We are also led
to understand that the young birds, being plump and tender, were more
highly esteemed than their more elderly and tougher relatives.
The most remarkable feature of this curious bird is its beak, the
peculiarities of which are its enormous size compared with the size of
the body, and its brilliant colours—blue, yellow, and red. For a long
time it was a puzzle that occasional dead specimens found washed ashore
in winter had a beak very much smaller and destitute of bright colours.
It has now been ascertained that the outer sheath is moulted annually,
being shed on the approach of winter and replaced at the return of the
breeding season.
To give any idea of their numbers on Sule Skerry is an almost impossible
task, for when they are on the island they are hardly ever at rest. The
air is black with them, the ground is covered with them, every hole is
tenanted by them, the sea is covered with them. They are here, there, and
everywhere.
They first make their appearance early in April, and spend from eight to
twelve days at sea before landing, coming close in round the island in
the forenoon and disappearing at night. Before landing they fly in clouds
round the place, and after having made a survey to see that all is right,
they begin to drop in hundreds, till in half an hour every stone and rock
is covered. They do not waste time, but start at once to clear out old
holes and make new ones, and for burrowing they can easily put a rabbit
in the shade. Those who are not engaged in digging improve the shining
hour by fighting, and for pluck and determination they are hard to beat.
They are so intent on their work that I have often seized the combatants,
and even then they were unwilling to let go their hold of each other; but
when they do, it is advisable for the person interfering to let go also,
if he would avoid a rather unpleasant handshake.
After spending a few hours on the island they all disappear, and do not
usually land again for two days; but when they do come back the second
time there is no ceremony about their landing. They come in straggling
flocks from all points of the compass, and resume their digging and
fighting. They continue in this manner, never remaining ashore all
night till the first week of May. They spend very little time on the
construction of their nests, which consist merely of a few straws. The
greater number burrow in the dry, peaty soil, and their holes will
average at least three feet underground; but there are also an immense
number that lay amongst loose rocks and stones on the north side of the
island. The eggs laid there are always clean and white until the young
bird is hatched; but those laid underground in a day or two become
as brown as the soil, and seem more like a lump of peat than an egg.
During the time of incubation, which lasts a month, those not engaged in
hatching spend their time in fishing and resting on the rocks, and as a
pastime indulge in friendly sparring matches.
One easily knows when the young are hatched by seeing the old birds
coming in from sea with herring fry or small sand-eels, which are carried
transversely in their bills, from six to ten at a time. The sole work of
the parent birds for the next three or four weeks is fishing and carrying
home their takes to the young. Very little time is given to nursing.
They remain in the hole just long enough to get rid of their burden,
and then go to sea again. As the young ones grow, the size of the fish
brought home increases. At first it is small sand-eels from one and a
half to two inches long, but at the end of a fortnight small herrings and
moderate-sized sand-eels are the usual feeding. I noticed an old bird fly
into a hole one day with a bigger fish than usual, and, to see what it
was, I put in my hand and pulled out both birds. The tail of the fish was
just disappearing down the young one’s throat, but I made him disgorge
his prey, and found it to be a sand-eel eight inches long. How that small
bird could find room for such a dinner was really wonderful.
At first the young are covered with a thick coating of down, and probably
their appearance at this stage has given rise to the name “puffin,”
meaning a “little puff.” In a fortnight the white feathers on the breast
begin to show, and the birds are fully fledged in four weeks, when they
at once take to the water. As soon as they go afloat, young and old leave
the place, and about the middle of July one can easily see that their
numbers are decreasing, the end of August usually seeing the last of them.
[Illustration: _Razor-bill._]
There is a considerable colony of razor-bills on the island. Their time
of arrival is about the same as that of the puffin, but they make no
commotion when they come. They seem to slip ashore, and always keep near
the coast-line, ready to fly to sea when any one approaches. They begin
laying towards the end of May, and lay one egg on the bare rock, usually
under a stone, but in some cases on an exposed ledge. During incubation
one bird relieves the other, for if the egg were left exposed and
unprotected the black-backed gull would very soon appropriate it. Some
authorities say that the male bird brings food to its mate; but I have
never observed this, though I have watched carefully to see if such were
the case The young remain in the nest, or, to speak more correctly, on
the rock, for about two weeks if not disturbed, and I have seen a young
one remain ashore until covered with feathers, which would mean about
four weeks from the time of hatching. They all, young and old, leave
early in August. I am sorry to say they are becoming scarcer every year,
chiefly on account of their shyness and fear of man.
The common guillemots are scarce. Their great haunt in this vicinity is
the Stack. There they are to be seen in myriads on the perpendicular side
of the rock facing the west. Only two or three pairs take up their abode
on the island; in fact their numbers scarcely entitle them to be called
Sule Skerry birds. The few young ones I have seen are carried to the
water as soon as they are hatched—at least they disappear the same day.
Black guillemots or tysties are plentiful. Their time of arrival is about
the middle of March, but they are rarely seen ashore before the end of
April. Their nests are to be found in out-of-the-way crevices or under
stones, and are not easily discovered on account of the extraordinary
watchfulness of the birds and their care not to be caught on or near
their nests. They lay two eggs, and the young are fully feathered before
going afloat. They remain about the island till the end of September.
[Illustration: _Oyster-catcher._]
The first of all the visitors to arrive are the oyster-catchers. They
first put in an appearance about the end of February, when their
well-known cry denotes that the long, dreary winter is over. They spend
their time till the end of March chiefly feeding along the coast-line;
but after that time they pair, and are seen all over the island. About
the end of May they lay three eggs in a nest composed of a few small
stones; and when the young are hatched the noise of the old birds is
perfectly deafening on the approach of an intruder, and even when no one
is annoying them the clamour they make almost amounts to a nuisance.
On calm, quiet nights it is hardly possible to sleep for them, and one
feels inclined to get out of bed and shoot them down wholesale. The young
leave the nest as soon as hatched, and are rarely seen, for on hearing
the warning cry of the parent bird they at once hide among the long
grass or under stones, and on one occasion I found a pair some distance
underground in a rabbit’s hole. They all leave the island during the
first half of September.
Next to the puffins in numbers are the terns—the Arctic terns. They are
also like the puffins in the regularity of their arrival at the island.
When first seen they are flying high up, and they continue doing so for a
day or two, only resting at night. There are several varieties of terns
scattered all over the British Isles, but in the north the most numerous
are the Arctic and the common tern. The latter rarely visits the island.
[Illustration: _Arctic tern._]
There are certain localities where the terns take up their abode, and
they stick closely to the same ground year after year, never by any
chance making a nest twenty yards outside their usual breeding ground.
They begin to lay in the first week of June, but I have found eggs on
the last day of May. They lay two eggs, and sometimes three. When the
young are hatched the parents are kept busy supplying them with food,
which consists chiefly of sand-eels and herring fry. Their method of
fishing is to hover over the water, not unlike the way a hawk hovers
when watching its prey, and when they see a fish to make a dart on it,
rarely if ever failing to make a haul. They also prey on worms when
it is too stormy for fishing at sea. On a wet evening, when the worms
are having an outing, the terns are to be seen in hundreds all over
the island, hovering about six feet above the ground, every now and
again making a dart down, and, when successful, flying home with their
catch to the young. No time is lost, for the old bird seldom alights
when handing over the worm. It swoops down to where the young ones are
standing with outstretched necks and bills gaping, screaming out to let
their whereabouts be known, and then flies off again for more. When the
young are able to fly they accompany their parents over the island, and
occasionally do a little hunting on their own account.
About the first of August the young are fully fledged. Young and old then
assemble from all parts of the island to a piece of bare rocky ground on
the north-east corner, which they make their headquarters for about ten
days, flying out to sea for food, but always returning at night. About
the fifteenth of August they all disappear, and are seen no more till the
following May.
[Illustration: _Stormy petrel._]
The island is the headquarters of a large colony of stormy petrels. It
is not an easy matter to fix the exact date of their arrival, for they
are never seen during the day, and only come out of their holes at night.
They are first seen in the latter end of June, when on a fine clear night
one can see them flitting about close to the ground, very like swallows
in their movements. They begin to lay in July, and their nests are to be
found under stones and in rabbits’ holes. Almost the only way to find
them is to listen for their peculiar cry, which they keep up at intervals
the whole night through. If captured during the day, they seem quite
dazed when released, and at once fly into some dark place. The date of
their departure, like that of their arrival, is not easily fixed, but I
think it is during September. Young birds have been got on the lantern at
night as late as the end of September, but never in October.
[Illustration: _Eider duck (male)._]
The eider duck is a regular visitor, and a considerable flock make Sule
Skerry their headquarters for about eight months in the year. They are
first seen in March fishing off the island, but they very rarely land
before the end of April. In May they may be seen ashore every day, but
always near the water, ready to pop in if alarmed. They are very shy and
difficult to approach. In June the duck and the drake both come ashore
and select a place for their nest, and that is the only occasion on which
the drake takes a part in the hatching process. So far as my observation
goes, I have never seen him approach his mate during the month of
incubation.
The nest is built sometimes on a bare rock, but more commonly among
grass, and consists of coarse grass for a foundation, the famous down
being added only as the eggs are laid. Five or six is the common number
found in one nest. From the time it begins to sit until incubation is
completed, the duck never leaves the nest unless disturbed, and will only
fly to sea if driven off. If approached quietly, it will allow one to
stroke it, and does not seem afraid. There are always one or two nests
close to the house, and though I have watched them closely at all hours,
night and day, I have never seen the birds go away for food, nor have I
seen their undutiful spouses bring any to them. I will not venture to
say that the duck lives a month without sustenance, but I am strongly
inclined to that belief. When frightened away, it goes only a short
distance, and returns immediately as soon as the cause of its fright has
been removed.
[Illustration: _Eider duck on nest._]
The whole inside of the nest is lined with down, which seems to be
intended only for the purpose of keeping the eggs warm. It is certainly
not intended to form a cosy nursery for the young, as they leave for the
sea a few hours after birth and do not return. Unless the down is removed
before the young are hatched it is useless, for it gets mixed up with the
egg-shells, which are always broken into very small pieces. After leaving
the nest the young birds rarely come ashore again, but remain afloat,
feeding along the edge of the rocks on mussels and crustaceans. The old
birds disappear in October, but some young ones remain till the end of
November.
[Illustration: _Kittiwake._]
Few kittiwake gulls visit the island, but these come regularly, and take
up their abode on the same ground year after year. They arrive in April,
and about the first of May begin nest-building, a work which keeps them
employed for about three weeks. They begin laying about the end of May,
and lay three eggs. The young are fully grown before leaving the nest,
and are fed by both the parent birds. They all leave the island about the
end of August, and not even a straggler is seen till the following spring.
[Illustration: _Curlew or whaup._]
I have now gone over all the birds that breed on Sule Skerry, and come
next to the regular winter visitors, consisting of the curlew, the snipe,
the turnstone, and the common sandpiper.
About a dozen curlews or whaups make the island their home for about nine
months of the year. They leave about the end of May and return in August,
remaining on the island all winter. Their number always keeps about the
same—twelve or fifteen. They have the same characteristics as those found
elsewhere—their extraordinary alertness and their peculiar cry—but they
are distinctly less shy than is usually the case in other parts of the
country. They are never disturbed in any way, and the result is that, if
any one wished, it would be an easy matter to get within gunshot of them.
Their chief food is worms and insects, of which there is a plentiful
supply on the island.
When the curlews leave the island, a few whimbrels take their place, and
remain about six weeks. They breed in Orkney and Shetland, but though
they remain on the island most of the breeding season I have never yet
found a nest. I have spent many an hour watching them from the light-room
with the glass to see if they were sitting, and have gone over the ground
where they are most frequently seen, but could never find an egg or any
attempt at nest building. They are very much like the curlew in general
appearance, only much smaller.
[Illustration: _Snipe._]
The snipe leaves the island in May, and is absent about four months,
usually returning in October. None, so far, have ever nested on
Sule Skerry, and they all go elsewhere for that purpose. There is a
considerable number of them resident during the winter, larger in some
years than in others. They sometimes get killed by dashing against the
lantern at night, but it is not often they fly so high.
[Illustration: _Turnstone._]
The turnstone always spends the winter on the island, arriving about
the end of August or the first of September, and from then on till
April it spends its time feeding on insects. On Sule Skerry it is in
no way afraid of man, but rather the opposite, for it depends a good
deal on the lightkeepers for its livelihood in stormy weather. Whenever
the lightkeepers go to feed their hens, the turnstones gather from all
parts of the island and sit round at a respectful distance—about a dozen
yards—waiting for their share, which they receive regularly every day,
and they seem to enjoy it very much. The lightkeepers often turn over
big stones to enable the hens to feed on the insects which are there
in immense quantities. The turnstones have learned the meaning of this
operation, and whether the hens are present or not, they soon gather
round for a feast when one retires a short distance. A few specimens of
the common sandpiper always accompany them, but they feed more amongst
the seaweed along the coast-line, and are more afraid of the approach of
man.
[Illustration: _Sandpiper._]
Occasional Visitors.
We now come to the third class, the occasional visitors. These are the
wild goose, the mallard or stock duck, the teal, the widgeon, the Iceland
gull, the Sclavonian grebe, the heron, the kestrel, the hooded crow,
the rook, the lapwing, the golden plover, the redshank, the corncrake,
the water rail, the fieldfare, the redwing, the snow-bunting, the
starling, the song thrush or mavis, the blackbird, the water-wagtail, the
stonechat, the woodcock, the skylark, the twite or mountain linnet, the
robin, the swallow, the black-headed gull, and the little auk.
Wild geese pass the island on their way south in October, but very rarely
rest. Occasionally a flock will hover round for some time, but the sight
of a human habitation scares them away, and they continue on their way in
the direction of Cape Wrath. Last October half a dozen were seen resting
on the island one morning about eight o’clock. They seemed to be feeding
in one of the fresh-water pools, but all they would find there would not
fatten them. Sule Skerry is a very likely place for them to call at, as
it is right in their track when on the way to and from Iceland and Faroe,
but perhaps the island being inhabited causes them to give it a wide
berth. At any rate very few of them ever honour it with a visit.
[Illustration: _Mallard._]
The mallard pays the island frequent visits during the winter, two and
three at a time. They never stay long, for there is very little feeding
for them. They are particularly shy, resting only on the most outlying
parts, and seeming continually on the watch. Teal and widgeon are not
common. Of the former one sees a specimen or two every winter, while of
the latter only two have visited the island, and that was in March 1897,
when they stayed a few days.
In November 1895 an Iceland gull arrived on the island, and remained to
the end of February following. It became fairly tame, sitting the greater
part of the day near the house on the watch for any scraps of meat that
were thrown out. Hopes were entertained that it intended remaining
permanently on the island, but on the approach of the breeding season it
departed. In 1898 one stayed for a week in November; in the following
year another was seen on the 23rd of November. This one was fishing in
company with some common gulls, and occasionally flew over the island
quite close to the tower; but I did not see it alight, nor was it seen
again on any of the following days.
[Illustration: _Heron._]
The common heron every year spends a day or two on the island, generally
in October or November, but it never seems at home. They wander about
in search of food, but apparently do not find very much. When leaving
the island they always, without exception, fly in the direction of Cape
Wrath, but where they come from I cannot say, never having noticed them
arriving.
The hooded crow is an annual visitor, generally in November, and it
sometimes comes for a short visit in April. Two or three is the common
number at one time. There is, however, not much food for them, and on
that account their visit is soon over. A few rooks call about the same
time.
Every year in April the lapwings make the island a resting-place,
staying from a week to a fortnight. The place does not seem to suit them
for nesting purposes, for I have never seen them make any attempt at
nest-building. After resting and renewing their strength, they seek out
some more hospitable part of the country. Small flocks of the golden
plover also rest on the island on their passage north in March and April,
and again on their way south in October and November, staying from eight
to twelve days. There are also a few straggling visitors during the
winter.
The common redshank is a frequent visitor, staying perhaps a week at a
time, but it never nests on the island. In 1896 a corncrake’s well-known
song was heard during the greater part of June. It was heard again the
following season, but never since. The bird, however, is occasionally
seen in summer. The only way I can account for its silence is that the
goats and rabbits never allow the grass to grow to any length, and thus
there is no cover for it. I think most ornithologists are now satisfied
that this bird migrates to a warmer climate every year on the approach of
winter. Whether such is the case or not I do not feel prepared to say,
but from my experience of Sule Skerry I am quite satisfied it is only a
summer visitor there, and does not remain on the island all winter. The
water-rail pays the island a visit every winter, but I do not think
there is any danger of its being mistaken for the corncrake. They are a
little like one another in shape, but they are two distinct species, and
easily recognized.
[Illustration: _Water-rail._]
In October and November the island is visited annually by considerable
numbers of fieldfares, redwings, blackbirds, rock-thrushes, starlings,
and woodcocks. They generally stay from a week to a fortnight, and are
more numerous some years than others. Water-wagtails are rare visitors,
seen at various times of the year. Stonechats are also rare visitors,
only staying a few days in May. The skylark, so common everywhere else,
is a very rare visitor, and is only seen or heard once or twice during
the summer months. Robin redbreast is always seen in the autumn, and
generally stays a few weeks if the weather is moderate. The twite or
mountain linnet pays an occasional visit in summer, and stays for some
time; but I have never yet found a nest, and cannot say if it breeds on
the island. In June every year a few sparrows spend a fortnight on Sule
Skerry. Snow-buntings almost deserve the name of regular winter visitors,
for from October to March they are seldom long absent.
Last September I got a bird which I knew to belong to the grebe family,
but I could not be sure of its proper name, and I sent it to Mr. Harvie
Brown for identification. He informed me it was a Sclavonian grebe, a
bird not very common in this part of the country. In November 1897 I
found a dead specimen of the little auk.
[Illustration: _Solan goose._]
Though not a Sule Skerry bird, the solan goose deserves notice in this
paper. The Stack, distant four and a half miles, has been their chief
breeding place in Orkney for ages, and every year it is tenanted by
immense numbers. The rock is 140 feet high, rising perpendicularly on
the west, but sloping gradually from the water to the summit on the
east side. It is on this slope that the solans congregate, and no other
bird is allowed to trespass on their preserves. In May, June, July,
and August their numbers are so vast that any one seeing the rock at a
distance would imagine it was painted white or composed of chalk. Sule
Skerry, however, is too far distant to allow of one forming any idea
of their numbers, but looking at them with the glass one sees the rock
simply covered, and apparently as many flying about as resting. Lewis men
visit the place annually in August, and carry away a boatload of young
birds. Last year they came up to the rock, but there was too much surf
for a landing, and as the weather was threatening they headed for the
Sutherlandshire coast. That night the wind blew half a gale, and fears
were entertained that it would prove too much for them, for their boat
was small and hardly powerful enough to be so far from home; but a few
days later they again approached the rock. They again failed to negotiate
it, and after waiting for about an hour they made sail for home, and did
not return. The weather certainly favoured the solans on these occasions.
I have never seen a solan resting on Sule Skerry; they even carefully
avoid flying across the island, though they fish in immense numbers all
round, and sometimes within forty or fifty yards of the shore. They
usually begin to arrive in the vicinity about the end of January, and
their numbers continue to increase until the end of April, when they take
possession of the rock, and from then until the end of August their name
is legion. When the young are fledged, they gradually disappear, and from
the first of December till the last days of January they are not to be
seen.
Thus they go on year after year, a fraction of that great feathered
multitude which has come and gone since the earliest ages, and will
probably continue to come and go as long as the world lasts, some
arriving and departing in silence, others heralding their coming and
going with the wildest clamour. On this subject, and speaking of the
northern isles, Thomson the poet says:—
“Where the Northern Ocean, in vast whirls,
Boils round the naked melancholy isles
Of farthest Thule, and the Atlantic’s surge
Pours in amongst the stormy Hebrides;
Who can recount what transmigrations there
Are annual made? what nations come and go?
And how the living clouds on clouds arise,
Infinite wings! till all the plume-dark air
And rude resounding shore are one wild cry?”
J. TOMISON
(_“Orcadian Papers.”_)
[Illustration]
COMMON SEAWEEDS.
A severe storm has been raging for several days on our shores, and no
ship has dared to cross the Pentland. To-day a great calm has fallen upon
the face of the waters, and the sun shines clear in the sky. A walk by
the seashore on such a morning will afford an excellent opportunity for
collecting specimens of our seaweeds, and for studying their life-history.
Here they lie in all their varied colours, strewn on the beach like
autumn leaves in a forest. Now is our chance to secure some of those rare
and beautiful weeds that grow in the deeper water, and have been torn
off and driven ashore by the waves. If pressed and dried with care, they
will remain things of beauty for long. For this purpose we use squares of
stiff paper or card, on which we spread them out carefully under water.
When pressed, they will adhere to the paper by means of the mucilage
which they contain.
[Illustration: _Common seaweeds.—I._
A, _Sargassum_ (Gulf-weed), B, _Cladophora_. C, _Enteromorpha_. D 1,
_Fucus vesiculosus_. D 2, Receptacle of same, with eggs and sperms. D 3,
Egg, with sperms. E, _Polysiphonia_.]
The delicate fern-like or feathery fronds of those red seaweeds will
compare in beauty with the best of our flowering plants. This is all
the more wonderful when we consider their lowly origin. For the family
of the _Algæ_, to which the seaweeds belong, is the oldest and most
primitive of all the families of plants. To the Algæ most likely
belonged the first forms of life which appeared on the earth.
If we are fortunate to-day we may find a specimen of the famous Gulf-weed
(_Sargassum_), which gives its name to the Sargasso Sea, and which is
said to have cheered Columbus on his celebrated voyage of discovery. In
the tropical Atlantic it covers immense areas of the ocean, and it is
occasionally cast ashore on the Orkney coasts, drifted hither by the Gulf
Stream and the westerly winds. It is easily recognized by its numerous
little round air-bladders, each on a separate branch.
Now let us turn our attention to the seaweeds which we find growing
on the beach around us. In many a rock pool in the “ebb” we may see
a miniature forest of tiny weeds of beautiful colours and forms, a
veritable ocean garden. Near high-water mark we find here and there
in the pools pretty green algæ, some with broad, flat fronds, such as
the sea-lettuce (_Ulva_), and others with slender branching feathery
filaments (_Cladophora_). Many of the green algæ, however, prefer to live
in fresh water. If you make an aquarium, you will find the sea-lettuce
and the sea-grass (_Enteromorpha_) of great value in keeping the water
pure, owing to the amount of oxygen which they give out.
Farther down on the beach the rocks are covered thickly with algæ of an
olive-brown colour. The rocks, indeed, would fare much worse in a storm
if the seaweeds were not there to protect them, as the grass protects the
soil of the fields.
Look more closely at those big brown sea-wracks and you will notice
that the most common kind (_Fucus vesiculosus_) has little globular
air-bladders arranged in pairs along its flat, smooth-edged fronds. Each
blade has a distinct midrib, and where it divides, like all the Fucus
group, it splits into two equal branches. On some of the little end
branches you may see a yellowish swelling dotted over with minute knobs
and pores. These swellings are receptacles for holding the eggs and
sperms, which are contained in tiny cavities under each projecting knob.
Many seaweeds produce their fruit in winter, when the land plants are
sleeping and the fields are bare.
The microscopic sperms correspond to the pollen and the eggs to the
ovules of the flowering plants. But there is one wonderful difference.
The sperms of the Fucus can move about freely by means of two little
projecting threads or cilia. When the tide is out, both eggs and sperms
come to the door of their little houses by the help of the mucilage in
which they float; and when the sea comes back swarms of these sperms swim
away and wriggle about, till one of them comes in contact with an egg. It
adheres to and fuses with the egg, which thus becomes fertilized, and is
then able to give rise to a young plant. A similar process goes on in all
the plants of the Fucus group.
Here is one with notched or serrated edges (_Fucus serratus_), and
without air-bladders; there another well known to every schoolboy as the
“bell tang” (_Fucus nodosus_), with large air-bladders in the centre
line of the frond, and yellow fruit-bodies each on a branch of its own,
without any trace of midrib.
The air-bladders of the seaweeds are natural buoys, by means of which
the plants are kept erect in the water. The mucilage which makes them so
slippery to walk over is of the utmost importance, as it protects them
from drought when they are left uncovered by the tide. Seaweeds are very
simple in their structure, and have no true roots, stems, or leaves. They
do not need such organs, for every part of their body is in contact with
the water which contains their food-supply.
What are those tufts of reddish-brown threads growing all over the fronds
of this Fucus? That is a red seaweed (_Polysiphonia_), which often
makes its home under the shelter of a more hardy plant. In the red algæ
the sperms have no cilia, and cannot move about of themselves, but the
eggs have each a long thread, corresponding to the stigma of the higher
plants, and against this thread the sperms are driven by currents of
water.
The little Fucus known as “teeting tang” (_Fucus canaliculatus_) ought
not to be passed unheeded. It is often much relished by sheep and cattle.
You may know it by its greenish-brown colour and by the distinct groove
on one side all along its length. It is found only in the upper part
of the “ebb”. Another interesting plant of this group may be found on
the large rocks nearer low-water mark. It is called the “sea-thong”
(_Himanthalia lorea_), because its fructification grows out from a
button-shaped base into long, forked, thong-like branches.
[Illustration: _Common seaweeds.—II._
F, _Fucus canaliculatus_. G, _Himanthalia lorea_. H, _Laminaria
digitata_. I, _Rhodymenia_. K, _Chondrus crispus_. L, _Porphyra_.]
If the tide is far out, we shall be able to see the tops of the
“red-ware” standing out of the water, and some of the tangles will be
quite dry. These tangles belong to the _Laminaria_ group, the giants
among the seaweeds. They contain a large amount of iodine in their
composition, and that is why they are used for the manufacture of kelp.
Notice how firmly they cling to the sea-bottom by their strong holdfasts,
which have weathered many a storm.
An interesting feature in this group is their manner of growth. The
growing region lies at the junction of the stalk with the blade. You
will often find a specimen in which the old blade is being pushed away
on the end of the young one, ready to be broken off and cast adrift by
the waves. The stalk itself is perennial, but in some kinds of Laminaria
(_Laminaria digitata_, for example) the blade is usually torn into shreds
before it is thrown off.
A well-known ally of the tangles is the “merkal,” also called
“honey-ware.” You can tell it by the prominent midrib and the broad, thin
wing on each side, running all its length. This is one of the edible
seaweeds. Do you see this bright red palmate plant growing under the
shelter of the tangles? It is the common dulse (_Rhodymenia palmata_),
which may often be seen for sale on the streets of our cities. Examine
it well and taste it, and you will be able to recognize it in future,
however much it may vary in form or colour. But do not eat too much of
it, for it is said to be somewhat indigestible.
Another edible seaweed which has been widely used as an invalid food
may be found in the lower part of the “ebb,” often under the shelter of
larger plants. This is the Irish moss or carrageen (_Chondrus crispus_).
It is fleshy and pink in colour. A jelly is made from it which is
considered a great delicacy.
The purple laver (_Porphyra_) is perhaps the most valuable of the
seaweeds as a food, and is said to sell at a high price in Yokohama. In
form it resembles the sea-lettuce. Many other marine algæ have been used
as food, and none of them are poisonous. In North Ronaldsay the sheep
seem to esteem them highly as food.
The most important use of seaweed is to serve as food for various
kinds of molluscs, crustaceans, and fishes. The “plankton” of the
sea-surface—minute one-celled algæ—are very important in this way. What
grass is to the land animals, the marine algæ are to the living creatures
of the sea. When driven ashore by the waves, or when cut down by the once
familiar “hook,” the larger seaweeds are much used as manure for field
crops. They thus repay the debt they owe for any portion of their food
that may have come originally from the dry land.
Before returning from our walk let us haul down this small boat from
its “noust” and take a bird’s-eye view of the seaweeds in their natural
habitat. Through the clear water beneath us we can see the strange shapes
of the submerged vegetation, dense and tangled, with here and there a
lazy sea-urchin on the broad red-ware, and the sillocks actively swimming
around. But our oars are entangled in the “drew” (_Chorda filum_), so
full of annoyance and even of danger to the swimmer. Look at one of those
long threads. It is covered with hairs; it tapers towards both ends, and
its fructification extends along its whole surface. In structure it is a
hollow tube divided into many chambers.
What a variety of colours and shades we see as we look down on this
wonderful submarine scenery! We notice that near high-water mark green is
the predominant colour, and that the lower belt is mostly brown, while
here at low-water mark and beyond it, as well as under the shelter of the
sea-wracks and tangles, shades of red prevail. Beyond the depth of thirty
or forty fathoms seaweeds are extremely rare, owing to the want of light
at the sea-bottom: seaweeds, like other plants, cannot take in their food
in darkness.
Notwithstanding their varied tints, the fundamental colour of all
seaweeds is green, as you can prove for yourselves by boiling a few brown
specimens, or soaking them for some time in fresh water. You will find
that the other colouring matters are dissolved out, and only the green
is left. The red or brown pigments are probably of use in aiding or in
protecting the green colouring matter, chlorophyll, in its important work
of assimilating the food material.
[Illustration]
CRABS.
When I was a boy at school we frequently amused ourselves by catching
crabs. The scene of our operations was the Peerie Sea, where a wall had
been built along the shore. Here we used to gather, armed with a piece
of string and bait of some kind, and we often spent a whole long evening
perched on the wall, fishing for crabs. The Peerie Sea was a receptacle
for all kinds of refuse, and formed a happy hunting-ground for swarms of
crabs.
When one thinks of catching crabs, one may naturally imagine an excursion
to the shore during ebb-tide, and much turning over of stones and
seaweed. Our method was quite different. We made the crabs come to us.
Our bait was a piece of fish or anything of an animal nature, provided it
was fairly tough. No hook was necessary; we simply tied the end of the
string round the bait.
The baited line was let down into the water, preferably in the vicinity
of a crab, and drawn slowly along the bottom. If the animal was timid,
and not very hungry, he often scuttled off in a fright. Usually,
however, he was both hungry and fearless, and seized the bait at once,
trying to drag it in among seaweed or into a hole. Now came the exciting
part of the business. Our object was to haul him up before he quitted his
hold. The wall was high, and he required careful management. Sometimes
when he was drawn up out of the water he would let go, and fall back with
a flop into the sea again; sometimes he would hold on till he was drawn
up over the wall, and then we shook him off on the pavement behind.
[Illustration: _Common shore crab._]
Occasionally when we had no bait we would manage to land a crab with a
small stone or a cinder. So long as the stone lies motionless on the
bottom he pays no attention to it. As soon as it begins to move, drawn
along by the string, the crab rushes at it and seizes it with his claws,
and it is some time before he finds out his mistake. Not infrequently
he will allow himself to be drawn quite out of the water, clinging to
his find. It is very amusing to see the crab worrying a hard stone, then
dropping it when he has discovered it is not eatable, and then seizing it
again as it begins to move away from him, just like a kitten with a ball
of wool. Apparently he cannot resist the idea that movement means life.
The commonest kind of crab in Orkney is the green shore-crab. He is on
the whole a bold animal, but when frightened he runs away with great
speed. He moves sideways, and thus meets with less resistance from the
water than if he were to move directly forward. Usually, however, he does
not walk fast, but creeps over the bottom in a leisurely fashion. When
seizing his food he comes up to it “head on,” his nipping claws held wide
apart; when he is near enough, he suddenly brings them together, and
begins to tear up the food in little bits and pack it into his mouth.
His eyes are placed on the tip of movable projections, so that they
command a wide view. He cannot see behind him, however, or under his
body, and he usually keeps his eyes fixed in the direction in which he is
going. When he is resting, his eyes are ever on the watch. Every little
movement on the beach near him he notices at once.
The crab has a peculiar method of feeding. His mouth is just under his
head, and the opening is guarded by two flat jointed plates, one on
each side of his mouth. If you pull these two plates apart—after having
arranged with a friend to hold his pincers—you can see where his mouth
is, and you may notice two strong things which look like teeth. These are
really his jaws; they move from side to side, and not up and down like
our jaws. To see how he feeds, you must put him into a glass jar, and
look up from below while he is eating a bit of fish. He tears it up with
his pincers, and puts little bits into his mouth, the parts of which move
from side to side as he eats.
He is not very particular as to what he eats. He is, indeed, a cannibal,
and will eat the crushed leg of another crab as readily as anything else.
He is one of the most useful animals on the beach, however, and has been
called the scavenger of the shore. In fact, if one wishes to get the
flesh cleaned off the skeleton of any large animal, there is no easier
method than to lay it on the beach, well below high-water mark, and build
stones around it, leaving spaces between them to admit crabs.
As we have already said, the crab is bold and fearless. He is safe in
his coat of armour, and his pincers are powerful weapons of offence and
defence. When fighting he rears himself up and throws his nipping legs
far apart with the pincers wide open. He then looks a formidable animal;
and he really is formidable, for with these legs he can protect almost
any part of his body, and the strength of his grip is considerable.
Take up a dead crab and examine his biting leg. The different parts are
joined by hinges. Each hinge allows of motion only in one plane, but the
various planes are so adjusted that the limb can be moved in almost any
direction. Only one part of his body cannot be touched by his pincers,
and that is his back. If you wish to grasp a live crab with impunity,
seize him across the back just where his walking legs join the body. He
may struggle as he pleases, but he cannot nip you.
It is quite a common thing to find a shore crab with one or more legs
wanting, or with one large pincer and one small one. What is the reason
of this? It means that at one time or other the crab has had a limb torn
off in a fight, for the males are continually fighting with one another.
When a limb is lost it is not a very serious matter, for a new limb soon
begins to grow on again, and after a time becomes as large as the lost
one.
There are times, however, when the crab is by no means pugnacious. One
sometimes finds under a stone a crab which has hardly enough spirit to
lift his pincers in self-defence. On touching him one finds that he is
quite soft. What has happened to him? He has recently been casting his
coat; for, as the animal goes on growing within his shell, he becomes
too big for it, and the only thing he can do is to burst the shell and
come out of it, and then wait for a bigger one to grow. When he is thus
moulting, he is glad to crawl away and hide till he is able to face the
world again. Many of the empty crab shells that one picks up on the
beach are the old cast-off clothes of crabs still alive and vigorous. By
examining one of these we can see how thorough the process of moulting
is; not only are the shells of his back and his legs thrown off, but the
covering of his eyes, his feelers, his mouth parts, and even the inside
lining of his stomach,—for, strange to say, the wall of his stomach is
lined with the same kind of shell as the outside of his body.
The crab is formed for living in water, but he can stand long exposure
to the air. If you cover him with damp garden soil or peat mould he will
survive for days. The reason is that so long as his gills are kept damp
he can breathe and live quite well. The lobster breathes in exactly the
same way, and when lobsters are being shipped for the southern markets
they are put in boxes with layers of wet seaweed to keep them alive.
Have you ever seen the beautiful set of gills which the crab has? If you
find a dead crab that has been lying on the beach for some little time,
you can easily remove the upper shell, leaving the soft parts of the body
with the legs attached. Just above the attachment of the legs there is
a series of brown feathery-looking things which seem to cover the whole
side of the body. These are the gills. They lie in a special chamber,
occupying about half of the whole space inside the shell. While the crab
is alive, the gills are continually bathed in a current of water, which
is pumped in through a small hole at the side of his mouth and drawn out
at another hole near it. If the gills become dry the animal soon dies.
There is a curious pointed flap folded tightly across the crab’s body
underneath, which is commonly called its “purse.” It used to be a
schoolboy belief that the crab carries its money here. The fact simply
is that the purse is kept closed for the sake of protection, as the skin
underneath it is soft and might easily be injured in a fight.
You have all seen the long tail of the lobster, with its broad flaps at
the end. By suddenly bending its tail underneath its body the lobster is
able to propel itself backwards through the water at a great rate. The
crab and the lobster are, as you may know, closely related, and the purse
of the former corresponds to the tail of the latter. The purse or tail of
the crab, however, is always tucked up under the body, and is never used
for swimming.
Both animals carry their eggs on this part of their body, and you may
occasionally find a crab with its purse so full of eggs that it cannot be
closed. These eggs have a curious history. When they are hatched, it is
not a small crab that comes out, but a funny little creature not in the
least like its parent. It has a rounded body and a long thin tail, and
swims actively about. At this stage it is called a _zœa_.
By-and-by the creature settles down to the sea-bottom and casts its
shell. Its back is now broader and its tail shorter, and it is provided
with claws; but it is still quite unlike a crab, and swims freely about.
It is now known as a _megalopa_. Swarms of these may be found clustered
round seaweed and other floating substances, both near the shore and in
deep water. As it grows it again casts its shell, but it now tucks in
its tail and settles down in life as a real crab, though of course a
very small one as yet: you may find scores of them on the beach not much
bigger than a split pea.
Besides the green crab there are others which are common on the
sea-beach. One of these is the edible crab or “partan.” This crab lives
in somewhat deeper water than the other, and is of a dark reddish or
purplish hue on the back, while its under parts are white. It is not
nearly so quick and active in its movements as the green crab, but when
it does get hold of anything it has a stronger bite. In deep water it
grows to a giant size, and it is regularly caught in creels and sold for
food, as its flesh is firm and good to eat. The flesh of the green crab,
on the other hand, is much softer and less abundant, and it is not used
for eating. Strangely enough, all crabs turn red when boiled, whatever
their colour when alive.
Another curious crab is sometimes found in weedy pools on the beach. This
animal is of a spidery form, and is much more difficult to see than an
ordinary crab, for he is elaborately disguised. His back and legs are
grown over with hairy brown seaweed, and as he always lies among a mass
of similar weed it is impossible to detect him so long as he remains at
rest. When he does move, his movements are extremely slow. If you take
him out of the water, he looks a most uncouth creature as he feebly
sprawls about. Place him back in the bunch of seaweed from which he was
taken, and he immediately adjusts himself so as to become invisible. This
is his mode of escaping observation, for he is too slow and weak to be
able to defend himself.
Still another odd-looking crab may be found in deep water. This animal
has rather thin legs, while its back is somewhat pear-shaped, the pointed
end being directed forwards. It is, however, a much more active animal
than the last mentioned, and we may often see it from a boat as it climbs
about on the broad blades of the tangles. It is rarely found on the
beach, but the cast-off shell of the animal may be found on almost any
part of our shores.
One of the most interesting of our crabs is known as the hermit-crab.
He belongs to the family of soft-tailed crabs, and in shape is more
like the lobster than the other crabs we have mentioned. The hinder part
of his body being without armour, he is forced to seek an artificial
defence, and this he finds in the empty shell of a whelk or “buckie,”
into the spiral coils of which he inserts his unprotected tail. These
creatures are generally called hermit-crabs, because each lives in his
own separate habitation, like a hermit in his cell or like Diogenes in
his tub; but unlike these in their habits, they are so pugnacious that
they are also known as soldier-crabs.
[Illustration: _Hermit-crab (with anemone on shell)._]
Hermit-crabs may be found plentifully on the shores, of various sizes,
and inhabiting any kind of shell that they find to suit their size. If
we look into a shallow sand-bottomed rock-pool, we may see some of these
shells moving about at a rate to which they were quite unaccustomed
during the life of their builder and original occupier: we know at once
that each of these shells has now as a tenant one of those interesting
crabs.
By means of an apparatus at the extremity of his tail the hermit holds
firmly to his temporary abode, and he flattens himself closely against
the shell, leaving exposed only the one large pincer which is specially
fitted to bar the door against intruders. It is difficult to seize the
creature at all; and even when a grasp of any portion can be secured, the
hold of the tail is so firm that the animal runs some risk of being torn
apart rather than leave his shell.
A well-known writer on Natural History, the Rev. J. G. Wood, has given an
interesting account of the hermit-crab, from which we quote the following
paragraphs:—
“The combative propensities of these creatures are wonderful. If two
hermits of fairly equal size are placed in an aquarium, they are
not content with appropriating different portions of the vessel to
themselves, but must needs travel over it and fight whenever they meet.
This struggle is constantly renewed, until one of them discovers his
inferiority and makes way whenever the victor comes near. When they fight
they do so in earnest, tumbling over each other, and flinging about their
legs and claws with great energy. They are not at all particular about
diet so long as it is of an animal substance, and will eat molluscs, raw
meat, or even their own species. More than once when a hermit has died
I have dropped the body into the water so as to bring it within view of
another hermit. The little cannibal caught the descending body in one of
his claws very dexterously, and holding it firmly with one claw he picked
it to pieces with the other, and put each morsel into his mouth in a
rapid and systematic manner that was highly amusing.”
“When a hermit desires to change his habitation, he goes through a
curious series of performances. A shell lies on the ground, and the
hermit seizes it with his claws and his feet and twists it about with
wonderful dexterity, as if testing its weight; and after having examined
every portion of its exterior, he proceeds to satisfy himself about its
interior. For this purpose he pushes his fore legs as far into the shell
as they will reach, and probes every spot that can be touched. If this
examination satisfies him, he whisks himself into the new shell with such
rapidity that he seems to have been acted upon by a spring. Such a scene
as this will not be witnessed in the sea unless the hermit is forcibly
deprived of his shell, but when hermits are placed in a tank or vase they
seem to be rather fond of ‘flitting.’”
[Illustration]
HOPPERS AND SHOLTIES.
Of the great multitude of different animals which live on the seashore
possibly the most numerous are the little creatures known as “sholties”
or “Shetland sholties.” They are to be found on almost every beach. Their
peculiar shape, flattened on the sides, their habit of hiding in crowds
under stones or seaweed, their intense alarm when they are suddenly
exposed, and their vigour in escaping into a new hiding-place, are known
to every schoolboy. They look very different from their pugnacious
relatives, the crabs; they are feeble creatures, more ready to escape
from danger than to offer fight. Yet they are most interesting little
animals, and the more one watches their ways the more one comes to
understand their wonderful adaptation to their surroundings.
Though their general appearance is quite familiar, it is not so commonly
known that there are many different varieties of these creatures. As a
matter of fact, there are scores of different kinds, some living on the
beach, some just below extreme low-water mark, and others in the deep
sea. We shall concern ourselves here only with those that live on the
beach.
There are three common kinds which every one ought to know. Two of these,
curiously enough, though _beach_ animals are not really _sea_ animals.
They are hardly ever in the water; they live on the fringe of beach which
lies just above high-water mark. The sea reaches them but rarely, and
they never voluntarily seek the water. These two kinds are known as the
shore-hopper (_Orchestia_) and the sand-hopper (_Talitrus_), the latter
being found mostly on sandy beaches, where they make little burrows in
which to hide, and the former living under stones or among the decaying
seaweed on stony beaches. They both get their name of “hopper” from their
habit of leaping or springing into the air, by means of which they often
avoid capture by enemies. French people call them “sea-fleas.”
[Illustration: _Shore-hopper (Orchestia)._ _Sand-hopper (Talitrus)._
_Sholtie (Gammarus)._
(All magnified about three times.)]
The third variety, which is probably best known of all, and to which
the name of “sholtie” is here more especially applied, is that which
occurs farther down on the beach in places which are constantly wet with
sea-water. This animal (_Gammarus_) is much narrower in the body than
the other two, and some of its legs are bent backwards along its side,
so that by means of them it can run or crawl on its side. Indeed, when
out of the water this creature in quite unable to walk back uppermost;
whenever by any chance it does succeed in raising itself into what is for
most animals the normal attitude, it immediately topples over on its side
again. It can be readily distinguished from the other two forms by having
_two_ pairs of long, delicate feelers or antennæ in front of its head;
the hoppers have only one long pair of antennæ and one short pair.
All these animals, in spite of their small size, are near allies of the
crabs and lobsters. A naturalist would tell you that they belong to
the group of the _Crustacea_, this name being applied to all animals
of the crab tribe on account of the firm, crackly skin or shell which
surrounds them. The Crustacea are marked by other features in addition
to the possession of this hard exterior. They are all jointed animals,
their body being built up of a series of segments, each of which carries
a pair of legs or appendages of some kind, these appendages also being
jointed. In the crab and the lobster a number of segments have become
fused or welded together to form the front part or body of the animal. In
the group of animals to which the sholties belong the segments are all
distinct.
To understand something of the structure and the general habits of the
sholtie, all that we require to do is to collect a few specimens from
the beach and put them in a saucer with a little sea-water. They will
swim about in a very active fashion, the swimming being performed by
means of little fan-like appendages attached to the under part of the
animal just where the swimmerets are in the lobster. By the vigorous
strokes of these appendages the animal forces its way through the water.
These appendages are, however, of use in another way; the gills of the
animal are attached to them. Even when it is lying almost dry, or in
water too shallow for swimming, these appendages can be seen to work
regularly and rhythmically with a gentle flapping movement. Sometimes
they stop working for a little and then begin again, but they are never
long at rest. In this way currents of water are made to bathe the gills
continually, and the flapping of the appendages is really a breathing
movement.
The walking legs are attached to the fore part of the body. Some of them
point backwards, as has already been mentioned, and the animal prefers
to crawl or run on its side. As a rule, too, it propels itself over the
ground by jerking movements of its body, its tail being alternately
curled up and then suddenly straightened out again. It is in this way
that it wriggles over the stones and escapes into a place of safety when
exposed.
One of the most characteristic points about the sholtie is its habit of
clinging to objects, especially if they afford a cover from the light.
Drop a bit of seaweed into the dish where they are swimming, and in two
or three minutes the sholties will all be found clinging to the under
surface of the weed. We might indeed imagine that they had escaped
from the saucer. They cluster like swarming bees round the smallest
blade of seaweed, and it is only by turning over the weed that we can
make sure that they are there. When exposed to full daylight they seem
uncomfortable, and keep swimming about trying to find a hiding-place. It
is only when they find something to cling to and to hide under that they
really rest and feel at ease.
But we have not yet examined the hoppers. Though externally so like
the sholties, they are very different in constitution and habits. To
understand the difference between the two classes of animals, the best
plan is to put either a shore-hopper or a sand-hopper into some water
along with a sholtie. The latter is an active little animal in the water,
capable of moving about like a fish. The hopper, on the other hand, is
obviously out of his element; he sinks to the bottom of the dish and
there works his way along in lumbering fashion. His breathing organs can
be seen waving backwards and forwards in rhythmical fashion, but they are
too feeble to be used for swimming. The shore-hopper can breathe quite
well in water, and may live in it for days. It is said that sand-hoppers
do not stand long-continued immersion, and die of drowning.
On land, however, the hopper is at home, provided he gets just
sufficient moisture to keep his gills damp. Not only can he crawl about
back uppermost—a feat which the _Gammarus_ would attempt in vain—but
as he crawls he keeps his tail curled up under his body, and by
suddenly straightening this out he can throw himself into the air with
considerable vigour. In this way he often not merely escapes from an
enemy, but even drives terror into the heart of the pursuer. It takes
some little time to realize that hoppers can be handled with impunity,
and are harmless for all their sudden jerky movements.
Why do these animals live on the upper fringe of beach, and what do they
find there to eat? The answer is simple. They live on the cast up refuse
of the sea; they are the scavengers of the jetsam. Naturalists who are
collecting the skeletons of small animals often put the carcases which
they wish to have cleaned under some decaying weed on the beach. After a
week or a fortnight the bones are found to be picked absolutely clean.
In order to tell the sand-hopper from the shore-hopper we have only to
look at his front feet. If they are all thin and slender, the animal is
a sand-hopper; if one pair of the front feet are clubbed at the end and
armed with a claw, we know that he is a shore-hopper.
[Illustration]
SEA-ANEMONES.
When the tide ebbs and leaves the rocks exposed we may find here and
there a few soft, rounded objects attached to the bare rock, often bright
red in colour, and looking like strawberries or ripe cherries. They are
found especially on the sheltered sides of high rocks and in the angles
formed by slight ridges and clefts. We do not seem to have any local
name for these objects, although they are so common and conspicuous; one
wonders why our name-inventing forefathers did not bestow on them some
descriptive title. Their English name is “sea-anemone,” a term derived
from their resemblance to the anemone flower.
It is only when they are covered by the water, however, that they deserve
the name of anemone, for then they open out like a bud and spread out
circles of leaf-like projections, much as an opening daisy or dandelion
does. They usually remain open during the whole time that the tide is
up; when the water goes back again these leaves all curl in towards the
middle of the anemone and are folded up inside, leaving only a little
dimple on the top to indicate where they have disappeared.
Sea-anemones, however, are by no means flowers. Their jelly-like
consistency and their habits would lead us to classify them as animals,
and this they undoubtedly are. Though they seem to be rooted to one spot,
and to open and close like a plant, their real habits are those of an
animal. As a matter of fact, they are carnivorous animals; they first
kill their victims by poisoning them, and afterwards devour them. If they
had the power of moving rapidly in pursuit of prey, they would be as
deadly to the general population of the beach as are the most venomous
snakes to the creatures on land. As it is, they account for a very
considerable number of the beach inhabitants by simply lying in wait and
grasping the little animals that happen to stray within their reach.
[Illustration: _Sea-anemones._]
The beautiful circles of leaflets which we see so regularly arranged are
really active grasping tentacles, armed with whole batteries of little
poisonous stings. With these tentacles they seize hold of any little
creature, such as a “sholtie” or a young crab, that happens to move
over them. The poor animal is held fast in spite of all its struggles,
tentacle after tentacle is brought up by the anemone to grasp it, while
hundreds of fine stinging darts discharge into it their poison, and
the victim, its struggles gradually becoming more and more feeble, is
ultimately drawn into the centre of the animal, where lie its mouth and
its stomach. Then the tentacles are all closed in over the prey, and
remain thus closed for a time—a day or several days, according to the
size of the animal caught. During this time the process of digestion is
going on, and when it is completed the skeleton and useless parts of the
animal are discharged by the same opening as that by which it was taken
in, and the anemone once more spreads its tentacles to wait for its next
victim.
It is not only living animals that the anemone will devour. Anything of
animal nature, dead or alive, is grist to its mill; and though it has
no eyes, it can quite well distinguish what is good for food. A waving
branch of seaweed borne towards it by currents in the water is quite
ignored, while a bit of flesh is never allowed to come in contact with
the tentacles without an effort being made to secure it. By some natural
power, whether by the sense of smell or of taste or by some other sense
unknown to us, the creature distinguishes unfailingly what it needs. It
is great fun to feed it with small portions of limpet or of whelk, and by
doing so one can see exactly how the process of feeding is carried on.
One might imagine that the anemone would easily fall a prey to larger
and stronger animals. It has no hard skin or shell to protect it, and
its beautiful jelly-like appearance would suggest to any hungry fish or
crab that it is not only easy to demolish but would form a juicy morsel.
Yet it does not seem to be in any danger from such enemies. I was once
amusing myself by throwing little pieces of bait into the sea among a
crowd of sillocks. Along with the bait, which consisted of limpet and
fish, I threw in a morsel of one of these red anemones. A bold young
sillock immediately snapped it up. Then something seemed to go wrong, for
the poor young fish suddenly shot the anemone out of its mouth and swam
off without so much as looking at the other bait which I threw all round
about it. The piece of anemone was less palatable than it looked.
Strangely enough an anemone is not much inconvenienced by being cut into
bits. The individual pieces if put into the sea again close up and grow
into new animals. No doubt the piece which the sillock swallowed was
fully alive, and stung the mouth and throat of its captor so severely
that the fish was only too glad to be rid of it.
All anemones are not red in colour like those of which we have been
speaking. There is a great number of different kinds of these creatures
round our shores, but most of them are only to be found by careful
searching. Some are found in rock-pools; these are generally coloured
more or less like the seaweeds in the pools. Others are found only in
dark places; under large stones or boulders near low-water mark they grow
in all attitudes—upright, sideways, and upside down—attached by their
base to the surface of the stone. The greatest variety of them I ever saw
was found among the stones of a little jetty or pier, which was being
taken down to make room for a larger pier. The under surface and the
sides of the stones on this pier were simply covered with anemones of all
sizes, shapes, and colours.
The various kinds of anemone differ not only in colour but also in size
and shape. Some are minute things, with a thin body or stalk crowned at
the top with long, fine tentacles, which they wave about actively through
the water in search for small prey. Others again are large, and one kind,
known as the dahlia, which is common in Orkney, attains to gigantic
proportions; when its tentacles are expanded it is as wide across the top
as the mouth of a large breakfast cup. The dahlia is variously coloured,
sometimes dark crimson, the tentacles being marked with broad rings of
crimson and white, sometimes green with red markings. The outside of
its body is usually covered with bits of gravel and broken shells, so
that when the animal closes up there is nothing to be seen but a rounded
heap of gravel. When open it is a magnificent creature, and its broad,
tapering tentacles shine with an iridescent light.
[Illustration: _Dahlia anemone._]