Spatial patterns of summer demersal fish assemblages around the Antarctic Peninsula and South Shetland Islands

Abstract

During the research programme conducted on the OV Puerto Deseado in the summers of 2011 and 2013, 36 stations were sampled using a demersal net at depths between 53-590 m in the Antarctic Peninsula and South Shetland Islands. A total 3378 fish specimens belonging to 36 species were recorded. Notothenidae was the best-represented family in species number, with Lepidonotothen nudifrons, L. larseni and Trematomus scotti being the most numerous species. Of the fish assemblages, 20% of the species were considered as dominant, 10% as common, 13% as occasional and 57% as rare. Six groups (and two sub-groups) were obtained by the ordination diagram based on geographical location: group 1 = Gerlache Strait, group 2 = Deception Islands, group 3 = Biscoe Island, group 4 = between Elephant and King George islands, group 5 = northern Antarctic Peninsula, and group 6 = South Shetland Islands, with sub-groups 6a shallower South Shetland Islands and 6b deeper South Shetland Islands. Sampling depth and water temperature significantly explained the spatial pattern. A latitudinal pattern of decreasing abundance from north-east to south-west was found in L. larseni and the opposite in T. scotti. The predictability of fish composition in the assemblages' areas could be a useful tool for ecosystem-based management.

Microsatellite markers for the notothenioid fish Lepidonotothen nudifrons and two congeneric species

“…Lepidonotothen nudifrons (Lönnberg 1905), the Gaudy notothen [ 1 ] is a benthic and moderately active fish species belonging to the family Nototheniidae (red-blood species, [ 2 ]). L. nudifrons is especially abundant along the Islands of the Scotia Arc until the Bransfield Strait (Antarctic Peninsula) [ 1 , 3 ]. This species plays an ecologically important role as prey to piscivorous fish species in this region [ 3 ], however, little is known about its genetic variability and the demography.…”

“…L. nudifrons is especially abundant along the Islands of the Scotia Arc until the Bransfield Strait (Antarctic Peninsula) [ 1 , 3 ]. This species plays an ecologically important role as prey to piscivorous fish species in this region [ 3 ], however, little is known about its genetic variability and the demography. Since the strongest local effects of climate change in polar regions were recorded for the Antarctic Peninsula [ 4 ], it is essential to investigate if L. nudifrons is experiencing any loss of genetic variability or if gene flow is limited among pools of individuals.…”

Ontogenetic changes in the feeding strategy of Lepidonotothen nudifrons (Pisces, Nototheniidae) off the South Shetland Islands and the Antarctic Peninsula

“…Lepidonotothen nudifrons (Lönnberg 1905) inhabits Antarctic waters between 3 and 400 m depths and is among the most abundant and broadly distributed demersal fish off the SSI and the AP (Llompart et al 2015). Reaching a maximum size of 220 mm total length and attaining sexual maturity at four or five years of age, it is small and slow growing (Hourigan & Radtke 1989).…”

New insights into reproductive physiology in Antarctic fish: a trial in Lepidonotothen nudifrons

“…Regarding its high local abundance, this species is considered ecologically important as relevant prey to piscivorous species (e.g. channichthyids and Dissostichus eleginoides) (Kozlov et al 1988;Kock 1992;Takahashi and Iwami 1997;Flores et al 2004;Llompart et al 2015).…”