Hinweis zum Urheberrecht
Bericht / Forschungsbericht / Abhandlung zugänglich unter
URL: https://epub.sub.uni-hamburg.de/epub/volltexte/2009/1590/
Distribution, population structure, growth and reproduction of the razor clam Ensis arcuatus (Jeffreys) (Solenaceae) in coastal waters of western Ireland
Weitere Beteiligte (Hrsg. etc.): Fahy, Edward
| Originalveröffentlichung: |
| (2001) http://www.marine.ie/NR/rdonlyres/38943BBB-47F4-4AA1-A3B7-C8AF75FDFCD6/0/ns10.pdf |
| pdf-Format:
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| BK - Klassifikation: |
| 42.73 , 48.67 |
| Sondersammelgebiete: |
| 21.3 Küsten- und Hochseefischerei |
| DDC-Sachgruppe: |
| Biowissenschaften, Biologie |
| Sonstige beteiligte Institution: |
| Irish Marine Institute |
| Dokumentart: |
| Bericht / Forschungsbericht / Abhandlung |
| Schriftenreihe: |
| Irish Fisheries Investigations |
| Bandnummer: |
| 10 |
| Sprache: |
| Englisch |
| Erstellungsjahr: |
| 2001 |
| Publikationsdatum: |
| 14.05.2009 |
| Kurzfassung auf Deutsch: |
| Samples of razor clams, Ensis arcuatus, the species which makes up the majority
of landings from the west coast of Ireland, were collected by commercial fishery
methods, in association with the dredge fishery and by SCUBA diving, from three
locations off the coast of Co Galway. E. arcuatus occupies coarse sand (of maërl
and shell fragments) and rarely co-exists with the other common species of the
region, E. siliqua. E. arcuatus were aged, an age-length-key devised for them, and
growth parameters (Linf, k and t0) were calculated. Their maturation state was
established by histological examination.
Evidence suggests that Ensis arcuatus is mainly a spring spawner, although some
spawning appears to take place in most months, with a spatfall in June/July.
Maturation commences in its third year. Asymptotic length is achieved at 10
years, approximately, and there was little variability in growth among the three
sampling areas or between the sexes. In a small bed of razor clams in Cill
Chiarain Bay, Co Galway, there would appear to have been a spatfall in most, if
not all, of the past 15 years.
The quantitative distribution of E. arcuatus in a single bay within the boundaries
of Comharchuman Sliogéisc Chonamara Teó, Co Galway, was estimated by
divers salting quadrats of 0.33 m². The razor clam community is divided into a
generally distributed fraction occurring at low density (described as the non-bed)
and at a relatively higher density (described as the clam bed). The bed was
situated in the lee of reefs, which is usually the case for this species along the
Atlantic seaboard. More than 90% of the biomass was above the E.U. minimum
size limit. |
