Biol. Clarke, K. R., and Gorley, R. N. (2005). Figure 5. The three dominant pelagic Themisto species showed significant seasonal, inter-annual and spatial variability (Figure 3), with high abundances in summer and lower numbers in winter. With an increase in the capelin stock from 1987–1991, a corresponding decrease in the abundance of Themisto abyssorum and T. libellula was observed. The new face of the Arctic. doi: 10.1007/978-1-4020-6774-7_4. J. Exp. Natl.

Themisto gaudichaudii, amphipod predator in the Southern Ocean. 69, 852–863. The sea ice is thinning (Hansen et al., 2013; Renner et al., 2014; Krumpen et al., 2015), and its extent is shrinking, with predictions of nearly ice-free summers in the Arctic within the next 25 years (Nghiem et al., 2007; Wang and Overland, 2012; Liu et al., 2013).
Biodivers. doi: 10.3354/meps008037. ICES J. Mar. are often segregated by depth in the water column according to sex and life stage (Williams and Robins, 1981; Wȩsławski et al., 2006). Deep Sea Res. doi: 10.1126/science.aai8204, Renner, A. H. H., Gerland, S., Haas, C., Spreen, G., Beckers, J. F., Hansen, E., et al.

(2010). 0000054132 00000 n

Mar. London: Pangaea, doi: 10.1594/PANGAEA.150005. R. Soc. Furthermore, a tendency of increasing T. libellula abundances toward the upper domain of the chart could be identified, and vice versa for T. abyssorum. Soltwedel et al. 64, 2734–2741. Population dynamics and body composition of the Arctic hyperiid amphipod Themisto libellula in Svalbard fjords. 41, 29–50. Bremen: University of Applied Sciences Bremen, 1–129.

Pteropod sedimentation patterns in different water depths observed with moored sediment traps over a 4-year period at the LTER station hausgarten in eastern fram strait. A funnel full of swimmers would also explain the prolonged event lasting until early September 2013, with swimmer material filling up the next sample cup entirely when it was exposed for sampling.

Reproduction can be nearly continuous but becomes more seasonal at higher latitudes.

Box 1870 Nordnes, N-5817, Bergen, Norway. 0000153950 00000 n The 260 species of hyperiid amphipods are large-eyed and planktonic amphipods, whereas gammarid amphipods have smaller eyes and tend to live on the sea floor. According to the Norwegian Directorate of Fisheries (2015), catches of capelin, haddock, and herring declined between 2010 and 2014, whereas Atlantic cod (Gadus morhua) catches increased by ∼30% for the same time frame.

Schematic map of the marine circulation patterns in the Fram Strait. 25, 656–666. The stock size of cod in the mid-1990s was about twice the amount as in the mid-1980s. doi: 10.1093/plankt/fbv052, Kraft, A., Nöthig, E.-M., Bauerfeind, E., Wildish, D. J., Pohle, G. W., Bathmann, U. V., et al. 0000064025 00000 n Diagnostic study of the Fram Strait marginal ice zone during summer from 1983 and 1984 Marginal Ice Zone experiment lagrangian observations. With this new dataset, we also analyzed the population structure of the three dominating amphipod species.

Given the high commercial value of Atlantic cod and haddock (Norwegian Directorate of Fisheries, 2015), a recently observed northward shift of Atlantic cod (Christiansen et al., 2016) and an enormous increase of fishing vessel sightings near Svalbard (Bergmann and Klages, 2012), the potential fishing pressure may remain high, relieving the amphipods from predation impact.

Two different localities were sampled over the period from September 2000 to July 2014 (Figure 1); sampling intervals lasted from summer to the following summer. Overall, T. abyssorum dominated the amphipod community by >50%. 118, 5202–5221. Weydmann, A., Carstensen, J., Goszczko, I., Dmoch, K., Olszewska, A., and Kwasniewski, S. (2014). a hyperiid amphipod from the Southern Ocean. 0000113285 00000 n 0000007370 00000 n 0000039974 00000 n Abundances of this North Atlantic species remained elevated compared to the mid-2000s, with noteworthy counts in late summer 2011. ICES J. Mar. 29, 1063–1070. The occurrence of the North Atlantic species T. compressa (Kraft et al., 2013) continued until 2014, which may be attributed to higher water temperatures (Supplementary Figure S1; Walczowski et al., 2017). Feeding, respiration and life history of the hyperiid amphipod Themisto libellula in the Arctic marginal ice zone of the Greenland Sea. doi: 10.1016/j.pocean.2006.09.007.

doi: 10.1007/s003000050295. 0000003818 00000 n doi: 10.1073/pnas.1219716110.

The three dominant amphipod species found in Arctic waters belong to the genus Themisto, namely the Arctic T. libellula, the Arctic-boreal T. abyssorum (both natives to the eastern Fram Strait), and the North Atlantic species T. compressa (Klekowski and Wȩsławski, 1991; Weigmann-Haass, 1997; Dalpadado et al., 2001; Dalpadado, 2002). Themisto libellula lives 2–3 years and grows to a maximum length of 31 mm (1.2 in). Sci. Variability in Atlantic water temperature and transport at the entrance to the Arctic Ocean, 1997-2010. Breaking the ice: large-scale distribution of mesozooplankton after a decade of Arctic and Transpolar cruises.

Themisto species were consumed by most age groups of cod.

doi: 10.5194/os-9-957-2013, Walczowski, W., Beszczynska-Möller, A., Wieczorek, P., Merchel, M., and Grynczel, A. Similarly, high T. abyssorum abundances contributed to the vertical clustering with highest values in the lower domain of the chart.

Figure 4. 0000067711 00000 n

This difference between sites coincides with a difference of ca. Preliminary studies of vent and seep systems in the Nordic Seas have identified the temperate-cold-water pelagic amphipod Themisto abyssorum as a potentially important predator in these chemosynthetic habitats.

We thank C. Lorenzen and E. Bonk (Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research) for lab assistance and the tedious work of swimmer picking. Themisto abyssorum and Themisto libellula were the dominant amphipod species observed in the central and the northern Barents Sea during 1984–1996. 39, 6–11. (Amphipoda) in the Barents Sea. In this study, newly analyzed data from a 3-years period (August 2011–June 2014) are presented, extending this long-term investigation. doi: 10.1016/j.dsr.2009.04.011, Beaugrand, G. (2009). They were identified to species level and life stage and counted. A., Fahrbach, E., Frolov, I. E., et al. 1% of the total individuals). These were higher at the northern HAUSGARTEN site compared to the central location (Figure 4). doi: 10.3354/meps004289, Keywords: sediment traps, hyperiids – pelagic amphipods, Arctic marine ecology, biodiversity, range shifts, Citation: Schröter F, Havermans C, Kraft A, Knüppel N, Beszczynska-Möller A, Bauerfeind E and Nöthig E-M (2019) Pelagic Amphipods in the Eastern Fram Strait With Continuing Presence of Themisto compressa Based on Sediment Trap Time Series.

0000050553 00000 n Sci. CNRS | INSU | UPMC | LOV | EPHE | AGROPOLIS | INRA | UNIV-ROCHELLE | B3ESTE | UNIV-MONTPELLIER | CEFE | SORBONNE-UNIVERSITE | SU-SCIENCES | UMS-2348 | UMS-829 | UNIV-MONTP3 | MONTPELLIER-SUPAGRO | INRAE | PSL. 37, 117–130.

Kortsch, S., Primicerio, R., Fossheim, M., Dolgov, A. V., and Aschan, M. (2015). Lett. Biol. 0000050725 00000 n meso- and macrozooplankton distribution and production of dominant herbivorous copepods during spring. No use, distribution or reproduction is permitted which does not comply with these terms.
0000154561 00000 n 58, 876–895.

0000004889 00000 n

Thus, the lack of T. compressa in the 2000/01 sample resulted in its strong dissimilarity with other samples.

Furthermore, increased T. libellula abundances mainly contributed to the vertical separation of the samples with increasing numbers in the upper domain. AK, AB-M, NK, and EB provided the data of amphipods, hydrography as well as trap, and mooring logistics and analyzed the respective data sets. For T. abyssorum and T. compressa, specimens <8 mm were considered as juveniles, whereas for T. libellula, the range <11 mm was chosen (lower size-limit: 2 mm, respectively), based on Kraft et al. The handful of species of the genus Themisto are the most abundant of all amphipods. Rapid reduction of Arctic perennial sea ice. 0000006819 00000 n (2014). Økonomiske Og Biologiske Nøkkeltal Frå Dei Norske Fiskeria 2014 (Economic and Biological Figures from Norwegian Fisheries 2014). Similarly, another hyperiid, Lanceola clausii, also increased in abundance over the investigated period.

(2012). Climate change alters the struccture of arctic marine food webs due to poleward shifts of boreal generalists. The map was created using ArcGIS 10.3 and based on the General Bathymetric Chart of the Oceans (GEBCO)-08 grid, version 20100927, http://www.gebco.net, with permission from the British Oceanographic Data Centre (BODC). 0000041495 00000 n 0000034343 00000 n Search for other works by this author on: Department of Fisheries and Marine Biology, University of Bergen, Bergen High Technology Center, © 2001 International Council for the Exploration of the Sea, Modelling the spatial–temporal distributions and associated determining factors of a keystone pelagic fish, Estimation and classification of temporal trends to support integrated ecosystem assessment, Prediction of square mesh panel and codend size selectivity of blue whiting based on fish morphology, The value of commercial fish size distribution recorded at haul by haul compared to trip by trip, Changes in growth and migration patterns of sea trout before and after the introduction of Atlantic salmon farming, About the International Council for the Exploration of the Sea, Receive exclusive offers and updates from Oxford Academic. Polar Biol. Res. Comparing food samples from diving and surface-feeding seabirds breeding in the Golfe du Morbihan at Kerguelen Islands to concurrent net samples caught within the predator foraging range, we evaluated the functional importance of the hyperiid amphipod Themisto gaudichaudii in the subantarctic pelagic ecosystem during the summer months. Nat. Sci., 14 June 2019 Thus, more temperate species evidently extended their range into the Arctic, as we demonstrated by the seasonal establishment of the North Atlantic species T. compressa. 0000152825 00000 n Polyakov, I. V., Beszczynska, A., Carmack, E. C., Dmitrenko, I.

0000058193 00000 n However, the record of Kraft et al. doi: 10.1007/s12526-010-0052-1, Kraft, A., Bauerfeind, E., Nöthig, E.-M., and Bathmann, U. V. (2012). Ecol.