The rocky subtidal assemblages of Kinsale Harbour (south coast of Ireland)
Ball, B.J.; Costelloe, J.; Könnecker, G.; Keegan, B.F. (1995). The rocky subtidal assemblages of Kinsale Harbour (south coast of Ireland), in: Eleftheriou, A. et al. (Ed.) Biology and ecology of shallow coastal waters. Proceedings of the 28th European Marine Biological Symposium, Crete, Greece, 23-28 September 1993. International Symposium Series, : pp. 293-302
In: Eleftheriou, A.; Ansell, A.D.; Smith, C.J. (Ed.) (1995). Biology and ecology of shallow coastal waters: Proceedings of the 28th European Marine Biological Symposium, Crete, Greece, 23-28 September 1993. International Symposium Series. Olsen & Olsen: Copenhagen. 361 pp., more
In: International Symposium Series. Olsen & Olsen: Fredensborg, more
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| Available in | Authors |
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Document type: Conference paper
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| Keywords |
Substrata > Artificial substrata
Ophiothrix fragilis (Abildgaard in O.F. Müller, 1789) [WoRMS]
ANE, Ireland [Marine Regions]
Marine/Coastal |
| Author keywords |
rocky substrata, artificial substrata, epifauna, Ophiothrix fragilis |
| Authors | | Top |
- Ball, B.J.
- Costelloe, J.
- Könnecker, G.
- Keegan, B.F.
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| Abstract |
The sublittoral epifauna of Kinsale Harbour, as revealed by extensive remote and in situ surveys, can be broadly assigned to the Lower Laminaria hyperborea Association (i.e. a well-documented epibenthic community of plants and animals from European seas). Owing to the frequently heavy layer of occluding precipitates, many epibenthic species are restricted to the vertical rock faces, oblique crevices and the underside of stones. A particular feature of the epifauna is the low number of both solitary and colonial tunicates. The bedrock over wide areas is covered by dense aggregations of the brittle-star, Ophiothrix fragilis, which also serve to inhibit the development of a prominent epifauna. Settlement colonization patterns were followed on introduced surfaces over the period 1983-1985. Within this experiment, a number of species settled out which had not been found on 'natural' ground. This is cautiously interpreted as suggesting the absence of suitable terrain under natural conditions. A study of the population dynamics of Ophiothrix fragilis, over the period 1983-1988 has shown the aggregations to be composed mainly of adult and juvenile specimens with variable numbers of intermediate-sized individuals. Mean density was calculated at 833 individuals· m-2. There is a single annual maturation with an extended spawning period. The predatory asteroid Luidia ciliaris, which is present in low numbers throughout the year, forages in 'herds' during the summer months. Despite such predation, the population of O. fragilis did not decline over the study period and, if anything, actually increased in density. |
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