Baffin Island Fjord Macrobenthos: Bottom Communities and Environmental Significance

Abstract

Cluster analysis of the benthos from ten Baffin Island fjords defines six faunal associations. The macrotidal Sunneshine Fiord has a shallow kelp-related Isopod Association. Cambridge Fiord supports a shallow Onuphid Association controlled by gravel from dropstones. A widespread Portlandia Association typified the shallow zones of more recently glaciated fjords where sedimentation rates are high. An Ophiuroid-Anemone Association was defined from current-affected submarine channel environments. A Maldanid Association covered the greatest area in all fjords and passed into an Elasipod Association in the deepest water in Cambridge Fiord.Fjord-head faunas are used to model ecological changes accompanying glacier retreat, from monospecific Portlandia, through mature Portlandia Association to Onuphid Association accompanied by diverse filter feeders and herbivores. Chlamys islandica was found living in Cambridge Fiord, which substantially increases its northern limit.

Macrozoobenthos of two Antarctic glacial coves: a comparison with non-disturbed bottom areas

“…The community associated with the area located close to the glacial stream (assemblage D) and characterized mostly by sandy-clay-silt deposits was dominated by eurytopic polychaetes: Mesospio moorei, Tharyx cincinnatus and Leitoscoloplos kerguelensis, as well as the bivalve Yoldia eightsi. The similar pattern was observed in the Arctic glacial bays and inner fjord areas with motile deposit The order of species in table is based on the dendrogram of Bray-Curtis similarity between the species (square-root-transformed data of mean density values in each assemblage and single link grouping method) Pol Polychaeta, Amp Amphipoda, Cum Cumacea, Tan Tanaidacea, Iso Isopoda, Ost Ostracoda, Act Actiniaria, Ast Asteroidea, Ech Echinoidea, Biv Bivalvia, Gas Gastropoda, Pri Priapulida (species associated mostly with one assemblage are grouped in boxes, the most abundant and frequent species within the groups are marked with bold) Polar Biol (2012) 35:355-367 361 feeding polychaetes (Tharyx, Leitoscoloplos, Cosssura) and bivalves like Yoldiidae and Thyasiridae as the important members of the communities (Syvitski et al 1989;Wlodarska-Kowalczuk et al 1998, 1999WlodarskaKowalczuk and Pearson 2004). Similar species composition was also observed in sites located close to the glaciers in Arthur Harbor (Richardson and Hedgpeth 1977) and in the polychaete communities inhabiting the shallows of Chile Bay (Gallardo et al 1988).…”

Quaternary glacial and marine environmental history of northwest Greenland: a review and reappraisal

“…Portlandia arctica today is absent from western Greenland, except for an isolated occurrence south of Thule, while Palliolum occurs in northern West Greenland, south of Thule (Thorson, 1951). Both are common in the fjords of Ellesmere Island and Baffin Island (Syvitski et al, 1989;Aitken and Fournier, 1993). Therefore, even though systematic investigations might turn up these two arctic species in the fjords of the Thule area, the area can be considered to be critical for them and their occurrence in fossil faunas indicates periods with a larger influx of Polar water than today.…”

Seabed images versus corer sampling: a comparison of two quantitative approaches for the analysis of marine benthic communities in the southern Weddell Sea (Southern Ocean)

“…The problems of sampling epifaunal benthos with corers are (a) the scattered abundance of large epifauna (e.g., hexactinellid sponges); (b) patchily distributed organisms (e.g., ophiuroids; Syvitski et al 1989) are underestimated; (c) motile organisms tend to avoid being caught by corers (e.g., Thurston et al 1994); and (d) the approaching gear may generate a bow-wave effect that flushes away smaller organisms. For further discussion about corers and other soft-bottom sampling gear, we refer to Blomqvist (1991) or Eleftheriou and McIntyre (2005), and further literature cited therein.…”