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Icelandic Waters (icelandic + water)
Selected AbstractsGroundfish species diversity and assemblage structure in Icelandic waters during recent years of warmingFISHERIES OCEANOGRAPHY, Issue 1 2010LILJA STEFANSDOTTIR Abstract Elevated ocean temperatures have been predicted to lead to a poleward shift in the latitudinal distribution ranges of fish species. Different responses of fish species to increased temperatures might lead to changes in assemblage structure and local species richness. In this study, the assemblage structure and diversity of groundfish in Icelandic waters were examined using data from a standardized groundfish survey conducted annually in 1996,2007. We used hierarchical cluster analysis to define assemblages in two time periods and canonical correspondence analysis to explore the relationships between the assemblages and temperature, depth, latitude, longitude and year. We further used two estimates of diversity, species richness and the Shannon index. Four major species assemblages were identified. Assemblages in the hydrographically stable deep waters north of the country were consistent during the study, while assemblage structure in the more variable shallow waters underwent some changes. For this period of generally increasing sea temperature, the canonical correspondence analysis also revealed a shift towards species representative of warmer temperatures. Diversity was shown to be highly variable both temporally and spatially, and also to vary with depth and temperature. Species richness increased with temperature and time southwest of the country, but decreased northeast of the country. The different trends detected between the northern and southern areas illustrate the importance of performing analyses at the most appropriate scale. [source] Growth, maturity and fecundity of wolffish Anarhichas lupus L. in Icelandic watersJOURNAL OF FISH BIOLOGY, Issue 4 2006Á. Gunnarsson Fecundity, maturity and the relationship between growth and maturity of common wolffish Anarhichas lupus were studied in Icelandic waters. A total of 788 female common wolffish were sampled in two areas: one in the relatively warm sea west of Iceland and the other in the colder sea east of Iceland. No difference was detected in fecundity of common wolffish between areas. The time from the onset of the cortical alveolus stage until spawning, was on average, 10 years in the east and 8 years in the west area. Common wolffish in the east area reached cortical alveolus stage, on average, at a greater age but similar size compared to common wolffish in the west area. Similarly, common wolffish started spawning, on average, at greater age and larger size in the east than in the west area. Common wolffish grew faster in the west than in the east area. Spawning common wolffish grew faster than common wolffish at the cortical alveolus stage in both areas. The relationship between growth and maturity for common wolffish in Icelandic waters appeared to be related to temperature, characterized by fast growth and early maturation in the west and slower growth and delayed maturation in the east. [source] | ||||||||||