The Davis Strait - DCE - Nationalt Center for Miljø og Energi

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66 (phytoplankton) to consumers at higher trophic levels e. g. fish and their larvae; whales, primarily the bowhead whale (Balaena mysticetus) (Laidre et al. 2007, Laidre et al. 2010): and seabirds, e. g. little auk (Alle alle), a specialised zooplankton feeder on the large copepods of the genus Calanus (Karnovsky et al. 2003). Most of the higher trophic levels in the Arctic marine ecosystem rely on the lipids that are accumulated in Calanus (Lee et al. 2006, Falk-Petersen et al. 2009). Consequently, a great deal of the biological activity, e.g. spawning and growth of fish, is synchronised with the life cycle of Calanus. Zooplankton not only supports the large, highly visible components of the marine food web but also the microbial community. Regeneration of nitrogen and carbon through excretion by zooplankton is crucial for bacterial and phytoplankton production (Daly et al. 1999, Møller et al. 2003). Zooplankton, mainly the Calanus copepods, play a key ecological role in supplying the benthic communities with high quality food with their large and fast-sinking faecal pellets (Juul-Pedersen et al. 2006). Thus, vertical flux of faecal pellets sinking down to the seabed sustains diverse benthic communities such as bivalves, sponges, echinoderms, anemones, crabs and fish (Turner 2002, and references therein). 4.2.2 The importance of Calanus copepods Earlier studies on the distribution and functional role of zooplankton in the pelagic food-web off Greenland, mainly in relation to fisheries research, have revealed the prominent role of Calanus. The species of this genus feed on algae and protozoa in the surface layers and accumulate surplus energy in form of lipids, which are used for overwintering at depth and to fuel reproduction the following spring (Lee et al. 2006, Falk-Petersen et al. 2009, Swalethorp et al. 2011). Most of the higher trophic levels rely on the lipids accumulated in Calanus mainly as wax esters. These can be transferred through the food web and incorporated directly into the lipids of the consumer through several trophic levels. For instance, lipids originating from Calanus can be found in the blubber of beluga and sperm whales, which feed on fish, shrimps and squid (Smith & Schnack-Schiel 1990, Dahl et al. 2000) and in the bowhead whale (B. mysticetus) and northern right whales (Eubalaena glacialis), which feed mainly on Calanus (Hoekstra et al. 2002, Zachary et al. 2009). Consequently, many biological activities – e.g. spawning and growth of fish – are synchronised with the life cycle of Calanus. In larvae of the Greenland halibut (Reinhardtius hippoglossoides) and sandeel (Ammodytes sp.) from the West Greenland shelf, various copepod species, including Calanus were the main prey item during the main productive season (May, June and July). They constituted between 88% and 99% of the biomass of ingested prey (Simonsen et al. 2006). Vertical distributions of the Calanus species are influenced strongly by ontogenetic vertical migrations that occur between the dark winter season and the light summer season. For the most of the light summer season Calanus is present in the surface waters. During summer and autumn, Calanus begins to descend to deep-water layers for winter hibernation, changing the plankton community structure in the upper water column from Calanus to smaller copepod and protozooplankton dominance. The grazing impact on phytoplankton by the smaller non-Calanus copepod community after Calanus has left the upper layer can be considerably higher than in spring. This is a result of shorter generation time and more sustained reproduction as well as relaxed food competition and predation by Calanus (Hansen et al. 1999, and references therein). The importance of small non-Calanus population in eco-
Figure 4.2.1. Calanus spp. biomass (mg C m -3 ). The coloured dots represent biomass values from different studies; red dots: from May 2006 in the 0-65 m column (Arendt et al. 2010), blue dots: from July 2000 (Pedersen & Smidt 2000) at 0-100 m, dark grey dots: from June-July 1996 (Munk et al. 2003) at 0-60 m column. The biomass values of Calanus spp. summer and an autumn period show higher biomass values east and west of the fishery banks. Seasonal descent of Calanus towards winter hibernation is presumed to have begun in July-August. Note: Biomass values are calculated based on different length-carbon regressions and using different sampling gear e.g. net types vary between studies. system productivity can be greater than implied by their biomass alone (Hopcroft et al. 2005, Madsen et al. 2008). 4.2.3 Zooplankton in the Davis Strait Knowledge of zooplankton in the assessment area is based on studies covering a 34-year time series from the 1950s by Pedersen & Smith (2000) and recent studies covering most of the southwestern coastal zone (Pedersen & Rice 2002, Head et al. 2003, Munk et al. 2003, Pedersen et al. 2005, Arendt et al. 2010). The coastal studies in Southwest Greenland clearly corroborate the hypothesis that most of the biological activity in the surface layer is present in the spring and early summer in association with the spring bloom and appearance of the populations of the large copepods Calanus. Calanus occurrence is widespread in the West Greenland waters, where high biomass values have been recorded across the fishery banks in Southwest Greenland, and is almost exclusively dominated by C. finmarchicus (Pedersen et al. 2005, Arendt et al. 2010) (Fig. 4.2.1). 66°N 64°N 60°W 60°W Calanus spp. biomass Survey period ! May 2006, 0-65 m column 62°N ! July 2000, 0-100 m column ! June-July 1996, 0-60 m column Biomass (mg C m -3 ) ! 0.001 - 5 ! 5 - 10 ! 10 - 20 ! 20 - 50 ! 50 - 100 ! 100 - 150 0 60°N Assessment area 75 150 Km ! ! ! ! 55°W ! ! ! ! ! ! 55°W ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 50°W 50°W 68°N 66°N 64°N 62°N 67
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THE DAVIS STRAIT A preliminary stra
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AU THE DAVIS STRAIT A preliminary s
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Contents Preface 5 Summary and conc
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Preface The Bureau of Minerals and
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anks are normally ice free or have
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ed in large numbers in the assessme
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cetaceans (whales and harbour porpo
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placement and transport corridors.
Page 17 and 18: shrimp and Greenland halibut, for i
Page 19 and 20: Mitigation The risk of accidents an
Page 21 and 22: Miljøet Det pelagiske miljø De fy
Page 23 and 24: Fangst og udnyttelse Menneskelig ud
Page 25 and 26: Indenfor fiskeriet, er risikoen for
Page 27 and 28: Kumulative effekter Der vil være e
Page 29 and 30: dybde, kan muligvis ændre på konk
Page 31 and 32: ingsæl, spættet sæl, finhval, pu
Page 33 and 34: tassannga misilittagarineqalersut s
Page 35 and 36: Timmisat imarmiut amerlasoorsuit, q
Page 37 and 38: lu klimami pissutsinut atuutunut tu
Page 39 and 40: toqunartoqarneri arrortikkuminarner
Page 41 and 42: toqusarnermik taarserneqarluni, uum
Page 43 and 44: minguttitamiit ajoquserneqarsinnaan
Page 45 and 46: Kalaallit Nunaanni immikkut ulorian
Page 47 and 48: Figure 1.1.1. The assessment area,
Page 49 and 50: VEC = Valued Ecosystem Components V
Page 51 and 52: tings/well and in total 6,000 tons
Page 53 and 54: 2.9 Other activities Ship transport
Page 55 and 56: Figure 3.2.1. Major sea surface cur
Page 57 and 58: 3.2.3 The coasts The coastal zone b
Page 59 and 60: Jan Feb May Apr May Jul Aug Sep Oct
Page 61 and 62: Figure 3.3.3. Average sea ice exten
Page 63 and 64: Figure 3.3.4. Major iceberg sources
Page 65 and 66: 4 Biological environment 4.1 Primar
Page 67: Figure 4.1.1. Monthly progressions
Page 71 and 72: 69 Fish larvae are important compon
Page 73 and 74: Figure 4.2.4. Red dots indicate san
Page 75 and 76: focus should improve our understand
Page 77 and 78: The coastal zone of the assessment
Page 79 and 80: 183 macroalgal species (excl. the b
Page 81 and 82: Table 4.3.1. Distribution of macroa
Page 83 and 84: Chaetomorpha capillaris Chaetomorph
Page 85 and 86: egistered in the area. A similar pa
Page 87 and 88: The sea ice algal production in the
Page 89 and 90: 1990) and then north (mid-2000s) in
Page 91 and 92: September when they have reached a
Page 93 and 94: Salmon, Salmo salar Biology and dis
Page 95 and 96: tween 1 and 2.4 billion individuals
Page 97 and 98: It should be noted that the breedin
Page 99 and 100: 66°N 64°N 62°N 60°W 60°W Arcti
Page 101 and 102: Knowledge on habitat use of the win
Page 103 and 104: Great shearwater, Puffinus gravis T
Page 105 and 106: Common eider, Somateria mollissima
Page 107 and 108: Figures 4.7.7. At-sea distribution
Page 109 and 110: Figure 4.7.9. Distribution and inte
Page 111 and 112: Figure 4.7.11. At-sea distribution
Page 113 and 114: The Iceland gull has a favourable c
Page 115 and 116: Figure 4.7.12. Distribution and int
Page 117 and 118: Murres spend very long time on the
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The puffins are migratory, but thei
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Figure 4.7.16. Density of whitetail
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sonal communication 1984) varied wi
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Numbers: The status of the walrus s
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tively impacted by disturbance from
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surround the eyes and line the oral
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Sensitivity: Non-whelping hooded se
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winter in reoccurring leads and pol
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Critical and important habitats: Th
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Figure 4.8.6. The main frequency ra
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tude breeding grounds and high lati
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Figure 4.8.7. Migration routes for
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long-finned squid (Loligo pealei) (
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Until recently the abundance of har
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Figure 4.8.9. Main summer and winte
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4.9.1 Pelagic hotspots The shelf ba
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5 Natural resource use 5.1 Commerci
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66°N 64°N 62°N 60°W Snow crab c
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Figure 5.1.4. Distribution and size
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Salmon, Salmo salar The fishery for
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Figure 5.2.2. Annual number of king
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2003/04-2007/08 the catch averaged
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66°N 64°N 62°N 66°N 64°N 62°N
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Figure 5.2.6. The West Greenland ca
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Figure 5.3.1. The number of cruise
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6.2 National nature protection legi
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formation see the IBA website (http
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glaucous gulls, great black-backed
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7.2 Conclusions on contaminant leve
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structures containing up to 10 ring
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The current warming trends are ofte
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species interactions. In the review
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8.5 Marine mammals and seabirds The
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9 Impact assessment David Boertmann
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10 Impacts of the potential routine
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Impact of seismic noise on zoo- and
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type or timing of vocalisations. In
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detailed studies on the effect of s
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Table 10.1.1. Overview of potential
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een eliminated on the grounds of en
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10.3 Development and production act
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hydrocarbon activities in Greenland
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parts of the shelf. Activities in t
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Seabird hunting is widespread and i
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There is a risk of reduced availabi
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General knowledge on the potential
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week period after the Exxon Valdez
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In general, species with distinct s
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A study of the density and distribu
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majority of the biomass. From a bio
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waters longer. The coastal fishery
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Seal pups are very sensitive to dir
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indicates that similar long-term im
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other parameters. It should be note
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Autumn (September-November) During
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to oil spills and produced water. I
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12.2.1 Ecotoxicological Monitoring
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Andersen JB, Böcher J, Guttmann B,
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Anon (2011b). Selvstyrets bekendtg
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Blackwell SB, Lawson JW, Williams M
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Born EW (2003). Reproduction in mal
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Buch E, Nielsen MH, Pedersen SA (20
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Clark RC, Finley JS (1977). Effects
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Dietz R, Heide-Jørgensen MP (1995)
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Falk K, Møller S (1997). Breeding
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Gjertz I, Kovacs KM, Lydersen C, Wi
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Hansen JLS, Hjorth M, Rasmussen MB,
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Heide-Jørgensen MP, Laidre KL (201
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Horsted SA (2000). A review of the
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Jonas RF (1974). Prospect for the e
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Ketten DR, Lien J, Todd S (1993). B
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Lick R, Piatkowski U (1998). Stomac
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Melle W, Serigstad B, Ellertsen B (
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Mosbech A, Danø R, Merkel FR, Sonn
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Nielsen OK, Lyck E, Mikkelsen MH, H
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Parry GD, Gason A (2006). The effec
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Popper AN, Fewtrell J, Smith ME, Mc
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Rivkin RB, Tian R, Anderson MR, Pay
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Schaaning MT, Trannum HC, Øxnevad
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Simpson AC, Howell BR, Warren PJ (1
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Taylor MK, Akeeagok S, Andriashek D
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Wegeberg S, Bangsholt J, Dolmer P,
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