The Rock-Pools of Bundoran

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<ul><li><p>The Rock-Pools of BundoranAuthor(s): J. E. DuerdenSource: The Irish Naturalist, Vol. 4, No. 1 (Jan., 1895), pp. 1-7Published by: Irish Naturalists' Journal Ltd.Stable URL: http://www.jstor.org/stable/25584877 .Accessed: 14/06/2014 03:11</p><p>Your use of the JSTOR archive indicates your acceptance of the Terms &amp; Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp</p><p> .JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact support@jstor.org.</p><p> .</p><p>Irish Naturalists' Journal Ltd. is collaborating with JSTOR to digitize, preserve and extend access to The IrishNaturalist.</p><p>http://www.jstor.org </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/action/showPublisher?publisherCode=injhttp://www.jstor.org/stable/25584877?origin=JSTOR-pdfhttp://www.jstor.org/page/info/about/policies/terms.jsphttp://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>Vol. IV. JANUARY, 1895. No. 1. </p><p>THE ROCK-POOI,S OP BUNDORAN. BY J. E. DU3RDEN, A.R.C.SC. (London). </p><p>I^A$T summer, in connection with the Royal Irish Academy Fauna and Flora Committee, I had the opportunity, in com </p><p>pany with Prof. Johnson and Mr. Mitchell, of spending a little over a week in and around Bundorau, a delightful watering place, much frequented by people from the North of Ireland. </p><p>My object was to collect representatives of all the Zoophytes, embracing under this popular term the Hydroids, Sea anemones, andPolyzoa, at the same time not neglecting other forms of life which I might chance to come across, </p><p>Bundoran lies at the south-east corner of Donegal Bay, about four miles from the historically interesting town of </p><p>Ballyshannon. Taking the former as our centre, we made </p><p>collecting excursions to different parts of the bay, and so ob tained a good idea of the resources of the locality. </p><p>West of Bundoran, cliffs of Carboniferous limestone face the </p><p>sea, dipping to the south at an angle varying from five to ten degrees; but at low water a considerable extent of shore is laid bare, diversified by numerous rock-pools, caves, and </p><p>narrow inlets of the sea, the happy hunting-grounds of the </p><p>naturalist. </p><p>In the rock-pools the first object which attracts one is the </p><p>Purple Sea-urchin Strongylocentrotus lividzcs, I^amk., occurring in great numbers in little hollowS&gt; their dark colour con </p><p>trasting strongly with the light rosy-pink calcareous alga Lithothanmion fiolyniorfthimfl, which lines most of these pools. This interesting sea-urchin is one of the most striking faunal </p><p>features of various localities along the west coast of Ireland, 1 For the name of this alga, and also for the others mentioned, I am </p><p>indebted to Prof. Johnson and to Mr. Mitchell, </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>2 The Irish Naturalist. </p><p>from Donegal Bay to Queenstown Harbour. It occurs nowhere else in the British Isles, but turns up again in the Channel Islands. It is capable of boring holes, probably by means of its teeth, in the soft limestone to a depth of one-half or more of its own height; where, however, the rocks, as at </p><p>Dog's Bay in Connemara, consist of the harder granite, the urchin is incapable of boringinto them, and simply rests upon the bottom of the pools. Many of them are partially covered </p><p>by empty shells, such as those of Patella, Purpura, ondLittorina. </p><p>Considering the spiny nature of their skeleton it is very diffi cult to conceive that this feature can be in any way concerned </p><p>with protection to the individual. Again, they are almost </p><p>invariably associated in the pools with luxurious growths of the light pink encrusting Lithothamnion polymorphum, to </p><p>which they offer the strongest contrast, almost suggestive of a </p><p>warning combination. </p><p>In some of the shallow pools, some distance above low water mark, we found numbers of the sea-slug Aplysiapunctata, Cuv,, their dark olive-green colour also contrasting strongly </p><p>with the light Lithothamnion. A few minutes sufficed to obtain two or three dozen, many of them in the act of laying their strings of brown-pink spawn. </p><p>On this part of the shore, and still more so on the rocks and cliffs north of Bundoran, are to be found more or less firm </p><p>masses of sand and fragments of shells built into tubes by the worm Sabellaria alveolaia, I4nn., and almost resembling a </p><p>honey-comb in appearance. These masses, no doubt, exer cise a preservative geological influence on the rocks, the hollows and irregularities about forming also a protection for various forms of life. </p><p>In one of the caves with a smooth floor covered by water, and with stalactitic and stalagmitic masses further in, we came across quite a crowd of small hermit-crabs, Pagurus, and very interesting it was to watch their little battles over the bodies of some of their unfortunate companions who had been torn from their protective gastropod shell. Here also I </p><p>met with a few specimens of Anemonia sulcata (Anthea cerms), Penn., of the variety with iridescent green tentacles tipped with red. This species, not so abundant in Donegal Bay, I have </p><p>met with in great numbers in Roundstone Bay, giving to the </p><p>beds of Zvstera there quite a flowery appearance. Actinia </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>The Rock-pools of Bundoran. 3 </p><p>equina, lyinn., of the varieties hepaiica, rubra, olivacea, and </p><p>viridis was present everywhere. Under one of the ledges of </p><p>rock I met with a large group, thirty or forty individuals, of </p><p>the pretty little Corynactis viridis, Allm. This anemone varies </p><p>much in colour, although those belonging to the same colony are generally alike. In the present case the column was of a </p><p>light brown colour, the margin a rich bright orange, and the </p><p>tentacles green at the base, with greenish-brown stems and </p><p>white knobs. At Roundstone I have met with colonies of the </p><p>more typical green form. Specimens of Heliaeiis hellis, E). and S. were present in the cavities of the rock-pools, and also </p><p>the large Tealia erassicomis, Mtill. in considerable variety of colour. A single example of Cylista undata, Mtill. was </p><p>also obtained. </p><p>The coast to the north of Bundoran is varied by steep </p><p>precipices and sandy shores. Around Claddaghlagan not </p><p>much was obtained, nor along the beach in front of the east </p><p>portion of the town. Rogy Bay, a narrow inlet, was the best </p><p>locality for material washed up from the sea. Here were </p><p>obtained stems of Laminaria with quite thick forests of </p><p>Seriularia operculata, L,inn., growing on them, presenting almost the appearance of a fox's tail. The roots of the </p><p>Laminaria also yielded several species of encrusting Potyzoa. I may here record one fact in which I have always found the </p><p>west coast of Ireland to differ from the east coast, namely, in </p><p>the amount of material from considerable depths washed </p><p>ashore by storms. On such occasions we find suitable places on the east coast literally strewn with zoophytes and other treasures from the deep. Tangled masses are rolled about on </p><p>the sand}*1 shores, composed largely of Hydrallmania falcata, I4nn., Seriularia abietina, Iyinn., Eudendrium ramosum, I/inn., </p><p>various species of Flustra and Crista, Vesicularia spinosa, T^inn., and heaps of other smaller forms along with them or growing upon them, the whole forming a very rich and easily obtained harvest. On the west coast, however, I have never found any of the species mentioned above washed ashore. It has often been disappointing upon going to some strand, where, under </p><p>similar conditions along the east coast, I should have obtained in a few minutes thirty or forty different species of zoophytes, to find practically nothing. Tullan Strand, extending a dis </p><p>tance of nearly two miles from the Fairy Bridge to the mouth A2 </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>4 The Irish Naturalist. </p><p>of the river Erne, was a good example. Even after a consider able storm during the night there was nothing washed ashore to rejoice the collector. The Rev. W. S. Green, to whom I have remarked this difference, considers that it may be largely due to the fact that on the east coast the greater amount of </p><p>trawling in the deeper parts disturbs and tears up the objects </p><p>growing upon the sea-bottom, and then during storms they are washed up on the shore. </p><p>The limestone forming the cliffs is very fossiliferous, this </p><p>feature attracting even the most casual observer. The rock seems in parts entirely made up of crinoid stems, some oi them exceptionally large in diameter. Other portions are almost entirely composed of Productus giganteus, while various fossil corals are in many places important components of the rock. In the limestone on the north side of Rogy Bay, towards Aughrus Point, the rock-pools are mostly deep vertical hollows, always full of water, and crowded at the surface with a great variety of red, brown, and green sea </p><p>weeds. On pulling these aside one is rewarded with a most </p><p>lovely sight of variously and richly-coloured sea-anemones, </p><p>covering the sides and. crevices of the rock. Especially abundant were </p><p>" the Orange Disc Anemone," and </p><p>" the </p><p>Snowy Anemone," now both regarded as varieties oi'Heliactu </p><p>venusta, Gosse; also Bunodes gemmacetis, E* and S., and in the darker corners large specimens of Tealia crassicornis, Mull </p><p>A few examples of Aplysia punctata, Cuv. were obtained here also in the shallower pools. </p><p>The rocks from Aughrus Point to the Fairy Bridge are toe </p><p>precipitous for any work to be done upon them ; but in the latter place one can easily collect along the base at low water </p><p>and also enter the Cathedral Cave near. We found -this. </p><p>exposed to the full force of the waters of the bay, to be an extremely rich locality. The sand-tubes of Sabellam </p><p>aheolata, I^inn. form, with the rocks, small hollows in whiel are little forests of zoophytes, such as Tubularia larynx^ E. and </p><p>S., Obelia flabellaia, Hincks, Campanularia flexuosa, Hincks and Plumularia setacea, Ell., and numerous smaller forms </p><p>growing upon these. Here was obtained the rare Halecium </p><p>tenellum, Hincks, the first undoubted record for Ireland, The surface of the rock also serves for the attachment oi </p><p>crowds of Mytilus edulis, I/inn., and a search amongst these </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>The liock-pools of Bundoran. 5 </p><p>well rewarded us. On one of the ledges overhanging a pool, on the floor of which were abundant Plaice, almost undistin </p><p>guishable from their resemblance to the colour of the sand, </p><p>we came across hundreds of the lovely Meiridium {Actinoloba) dianthus, Ell., of the brown and white varieties. Exposed at </p><p>low water they hung vertically almost like so many shapeless masses of mucus, each with a drop of water at the distal end, </p><p>Iyooping about amongst the Hydroids were numbers of the </p><p>Amphipod Caprella linearis, lyinn. Tubularia larynx, E- and S., was especially the home of the Nudibranch Bolts coronata, </p><p>Forbes, its rosy hues harmonising well with the light red </p><p>colour of the polypites. From the Fairy Bridge, Tullan Strand stretches for nearly </p><p>a couple of miles to the mouth of the Erne, and yielded very little to us, but the sand-hills overlooking it would well repay the entomologist. The shore towards Itildoney Point we </p><p>found unproductive, and then took our way to Coolmore, a </p><p>place from which accounts of collections in other branches </p><p>have already appeared in this Journal. Descending the Blue </p><p>Stairs we were disappointed to find the shore composed </p><p>largely of sandstone and limestone boulders derived from the </p><p>cliffs, and presenting a very meagre fauna. Going a little to </p><p>the south-west, however, we were again amongst the lime </p><p>stone rock-pools with a great abundance of life. The con </p><p>trast was most striking. Where the rocks were principally sandstone they presented quite a barren aspect, and life </p><p>appeared impoverished, while a few yards further when we </p><p>got on to the limestone, the rock-pools were replete with a </p><p>luxuriance of animal and plant life, much as we had found </p><p>west of Bundoran. </p><p>Dredging in Donegal Bay with the trawlers did not yield us </p><p>much* The bottom consists principally of sand, and the </p><p>dredge and trawl brought up little of what the fishermen </p><p>regard as refuse, but to the zoologist is a harvest. A day was </p><p>spent on the east coast of the promontory stretching between </p><p>M'Swyue's Bay and Inver Bay* Here the shore was again rich in deep vertical rock-pools filled with weeds, such as </p><p>Fucus, Laminaria, Ulva, Enteromorpha, Bryopsis, Codiunt, </p><p>Cladophora, Chondrus crisptis, Rhodymeniay Corallina offi </p><p>cinalis', Lithotkamnion polymorphum, and other rarer forms. </p><p>Hundreds of Metridmm (Actinoloba) dianthusyEU-&gt; hung from </p><p>This content downloaded from 185.44.77.38 on Sat, 14 Jun 2014 03:11:39 AMAll use subject to JSTOR Terms and Conditions</p><p>http://www.jstor.org/page/info/about/policies/terms.jsp</p></li><li><p>6 The Irish Naturalist. </p><p>the under surface of projecting ledges, and most of the other common forms of sea-anemones flourished luxuriously, sharing the decoration of the pools with numerous brightly coloured sponges. Trawling around the shore our boatmen discovered for themselves a rich locality for Sole, Plaice, and Brill. The Laminaria brought up was coated with miniature forests of Obelia geniculaia, I^inn. and other zoophytes. </p><p>Numbers of shells of Pccten maximus, I4nu. were obtained encrusted with various Polyzoa. In returning across the bay </p><p>we were alarmed by the proximity of four or ^n^ large cetaceans following the shoals of herring along with flocks of </p><p>gulls. From the rounded head, large, high dorsal fin,, and </p><p>white uuder-surface, there is no doubt that they were speci mens of the Killer Whale (Orca gladiator, I^acpa). In a small </p><p>interesting book on Ballyshauuou1 containing a chapter on its </p><p>Zoology and Botany, it is recorded that in the last century whales were so numerous in Donegal Bay that a whale-fishery was established, but owing to the general roughness of the sea it was unsuccessful, although aided by a grant of 500 from the Irish Parliament in 1736, and a grant of 1,500 </p><p>1111763. We left Bundoran and its rock-pools feeling that our time </p><p>had been most profitably spent, and bearing away representa tives of many of its marine treasures preserved in our jars for futu...</p></li></ul>