A5081285282- Marine and fisheries research
- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Isotope Analysis in Ecology
- Fish Ecology and Management Studies
- Marine Bivalve and Aquaculture Studies
- Fish Biology and Ecology Studies
- Ichthyology and Marine Biology
- Parasite Biology and Host Interactions
- Aquatic Invertebrate Ecology and Behavior
- Arctic and Russian Policy Studies
- Oceanographic and Atmospheric Processes
- Geological Studies and Exploration
- Environmental Toxicology and Ecotoxicology
- Cephalopods and Marine Biology
- Arctic and Antarctic ice dynamics
- Genetic diversity and population structure
- Ocean Acidification Effects and Responses
- Identification and Quantification in Food
- Food Industry and Aquatic Biology
- Environmental Policies and Emissions
Marine and Freshwater Research Institute
1996-2017
Instituto de Investigacións Mariñas
2003
University of Aberdeen
1984
Abstract Astthorsson, O. S., Valdimarsson, H., Gudmundsdottir, A., and Óskarsson, G. J. 2012. Climate-related variations in the occurrence distribution of mackerel (Scomber scombrus) Icelandic waters. – ICES Journal Marine Science, 69: . Based on long-term investigations sea temperature waters, five climatic periods are defined from mid-1880s until today. These a cold period between 1880 1920, warm 1921 1964, 1965 1971, one intermediate conditions (alternating cold) 1972 1995, finally 1996...
Abstract Valdimarsson, H., Astthorsson, O. S., and Palsson, J. 2012. Hydrographic variability in Icelandic waters during recent decades related changes distribution of some fish species. – ICES Journal Marine Science, 69: 816–825. Seasonal time-series temperature salinity around Iceland have been collected, with repeat observations at stations, since the start 1970s. After fairly cold years early 1990s, a reversal occurred mid-1990s period from 1996 to 2010 was one warmer, more saline water...
Large-scale circulation patterns in the North Atlantic may partition ocean basin into three semi-distinct gyre systems: Norwegian Sea, northern Atlantic, and western Atlantic. Zooplankton entrained these gyres be ecologically, reproductively, (perhaps) genetically distinct owing to geographic isolation different systems and/or by distance. Previous studies have demonstrated that populations of copepod Calanus finmarchicus eastern differ significantly haplotype frequencies mitochondrial 16S...
Since the early 1960s studies on zooplankton biomass and species composition have been carried out standard transects during late May June in waters north of Iceland. In 1970s were extended to also cover south, west, east island. The present article summarizes these long-term investigations spring for 62 stations 9 transects. Calanus finmarchicus usually constituted about 50–80% number animals samples. Other species/groups considerable importance certain areas C. glacialis, hyperboreus,...
An 18 year zooplankton time series from two standard sections differing in hydrographic conditions (Subarctic Water north of Iceland and Atlantic water south Iceland) was examined relation to hydrography phytoplankton dynamics, large-scale climatic changes the North Ocean, particularly Oscillation (NAO). The long-term mean abundance higher (∼160 000 individuals m−2) than that (∼120 m−2). Abundance fluctuated markedly between years. Copepods (mainly Calanus finmarchicus Oithona spp.)...
Standardized time-series sampling was carried out throughout 1997 at seven locations around the Northeast Atlantic to investigate regional variations in seasonal demography of Calanus finmarchicus. Sites ranged from an inshore location North Sea, where C. finmarchicus formed only a small component zooplankton (<10 mgC m−2 during spring and early summer), shelf south Iceland, Weathership M Norwegian species dominated (>2000 summer). The internal consistency demographic each site investigated...
The food of the Norwegian spring-spawning herring ( Clupea harengus ) in western part Sea was studied. Herring stomachs and concurrent zooplankton samples were collected on three cruises 1995 (April, May, June). Further, seasonal abundance examined at two stations located near shelf break east Iceland between March February 1996. A total 164 herring, ranging length from 24.1 to 40.0 cm, examined. feeding activity higher May June than April, as indicated by both proportion with (>95%) April...
The seasonal variation in abundance and development of Calanus finmarchicus, hyperboreus glacialis relation to hydrography chlorophyll (Chl) a was studied the Arctic waters East Icelandic Current north-east Iceland from March 1995 February 1996. sampling carried out at approximately monthly intervals on transect five stations extending 67°00′N, 13°55′W 68°00′N, 12°40′W. In April, May June, vertical distribution also investigated. Spring warming surface began May, with maximum temperatures...
Journal Article Seasonal cycle of zooplankton southwest Iceland Get access Astthor Gislason, Gislason Marine Research InstituteSkúlagata 4, PO Box 1390, 121 Reykjavík, Search for other works by this author on: Oxford Academic Google Scholar Olafur S. Astthorsson Plankton Research, Volume 17, Issue 10, October 1995, Pages 1959–1976, https://doi.org/10.1093/plankt/17.10.1959 Published: 01 1995 history Received: 27 March Accepted: 22 June
Abstract The abundance and development of the copepod Calanus finmarchicus southwest Iceland was studied in relation to phytoplankton biomass at three stations along a hydrographic gradient during period February-November 1991.Following increasing stratification nearshore April, spring bloom began shallow area culminated April-May. At greater distances from shore did not start until middle May consequently blooming later deep offshore area, probably culminating mid late May. number low...
This paper presents an analysis of zooplankton composition and abundance based on sampling over the depth range 0-50 m at nine transects (61 stations) during a hydrobiological survey Icelandic waters in May-June 1992. Zooplankton species distribution is considered relation to water masses topography. The biomass was highest oceanic areas northeast Iceland [∼⃒8-20 g dry weight (dw) −2 ], whereas lowest values were generally observed offshore southeast, south southwest (<2 dw ). Over shelves,...
Generalized additive models (GAMs) were used to test the hypothesis that changes in physical and biological environmental conditions affected by current climatic warming would negatively impact euphausiid populations North Atlantic. Two zooplankton time series used, one collected Marine Research Institute (MRI) on a transect south of Iceland during spring (1990–2011) other Continuous Plankton Recorder (CPR) survey (1958–2007) oceanic waters covering all months. Due limitations sampling gears...
Abstract The food of capel in, Mallotus villosus (MÜLLER), caught in July and November 1993 June-July 1994 the waters north Iceland was investigated. A total 716 stomachs capelin ranging length from 2.1 to 20.0 cm were examined. Of these 575 or 80 % found contain food. Empty most frequent amongst smaller classes more so winter than summer. On average stomach content only ca 2 mg dry weight November, while it 78 weight. Copepods numerically important identifiable component all classes,...
The waters north of Iceland are characterized by large hydrographic fluctuations. Warm and cold years distinguished on the basis hydrography. Time-series data reveal that zooplankton biomass, capelin weight-at-age all greater during warm than years. chain events links conditions with observed ecological variations is discussed.
This study aims to explain the distribution, maturity and population structure of Meganyctiphanes norvegica Thysanoessa inermis in springtime relation main hydrographic regions around Iceland: Atlantic southwest, Atlantic-Arctic mixture north Arctic east. Krill were collected 14-29 May 2013 using a macrozooplankton trawl. Biomass both species combined was significantly higher southwest than M. clearly dominated waters, whereas T. more evenly distributed island, while highest values also...