Sponge assemblages and predicted archetypes in the eastern Canadian Arctic

• Published in: Marine Ecology Progress Series
• Main Authors: Murillo, Francisco Javier, Kenchington, Ellen, Tompkins, Gabrielle, Beazley, Lindsay, Baker, Emily, Knudby, Anders, Walkusz, Wojciech
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Zenodo 2018
• Subjects: sponge grounds; biodiversity; community modelling; community structure; Significant Benthic Areas; Davis Strait; Baffin Bay; European Union (EU); Horizon 2020; Grant Agreement No 679849; Deep-sea Sponge Grounds Ecosystems of the North Atlantic: an integrated approach towards their preservation and sustainable exploitation; SponGES; Baffin; Cape Dyer; Climate change; Hudson Strait; North Atlantic; Northwest Atlantic; Ungava Bay
• Online Access: https://doi.org/10.3354/meps12589

Little information exists on the environmental requirements of sponges from the Canadian Arctic, increasing the necessity to establish baseline distribution data on sponge assemblages to predict their susceptibility to climate change. Here we describe the sponge taxa of Hudson Strait, Ungava Bay, Western Davis Strait and Western Baffin Bay collected by Canadian research vessel trawl surveys. A total of 2026 sponge specimens were examined, and 93 different taxa were identified with 79% identified to species, of which 2 are new to science, 1 recorded for the first time in the North Atlantic, 16 are new records for the northwest Atlantic, and 10 are new records for the Baffin Bay, Davis Strait and Hudson Strait sponge fauna. Taxonomic distinctness was higher north of Cape Dyer and south of Davis Strait, whereas the number of species reached a maximum in Davis Strait, which represents the southern distribution limit of the arctic sponge fauna along the slope in this region. Five sponge species assemblages were identified, some of which have been observed elsewhere, suggesting that they may be common to the North Atlantic and at the generic level to the global oceans. Two of the Baffin Bay−Davis Strait assemblages were characterized by large structure-forming astrophorids: one, with arctic species, found at mid-water depths in Baffin Bay and the other, characterized by boreal species, was found deeper, south of Davis Strait. Another assemblage characterized by glass and carnivorous sponges was found along the continental slope of western Baffin Bay. Candidate target indicator species are provided for future sponge community monitoring. ACKNOWLEDGEMENTS. This work was funded through DFO's International Governance Strategy (IGS) project 'Identification and Mapping through Predictive Modelling of Cold-water Coral and Sponge Species in the Sub-Arctic/Eastern Arctic' funded from 2015−2017 led by E.K. G.T. and F.J.M. were both funded through the NSERC Visiting Scientist in a Government Laboratory programme with source ...