Of the 504 species currently comprising the Arctic ichthyofauna, those with Atlantic–Arctic ranges comprise 58% of the total richness, followed by species with Pacific–Arctic ranges (20%), while those endemic to the Arctic region account for an additional 14% ( Chernova, 2011). Older groups eliminated during the rapid cooling of the Middle Miocene were followed by younger families invading the Arctic mainly from the Pacific via the opening of the Bering Strait 3–3.5 million years ago ( Andriashev, 1939 Savin, 1977 Mecklenburg, Møller & Steinke, 2010), while a few families have also invaded the region from the Atlantic (e.g., Gadidae, Anarhichadidae) ( Svetovidov, 1948 Mecklenburg, Møller & Steinke, 2010). Owing to its unique biogeographic and climatic histories, the Arctic Ocean has produced a distinctive fish fauna dominated by phylogenetically young families (e.g., Zoarcidae, Stichaeidae) ( Andriashev, 1939 Dunbar, 1968 Mecklenburg, Møller & Steinke, 2010). The rapid warming of the Arctic will likely result in significant changes to the entire ecosystem and this study therefore serves as an important baseline for the nearshore fish assemblages in this unique and fragile region. Another species group includes warmer-water fishes that are rare waifs (e.g., Glacier lanternfish Benthosema glaciale, White barracudina Arctozenus rissoi). Resident species have mainly high Arctic distributions, while transient species visit the archipelago to feed (e.g., Greenland shark), and others are brought by currents as larvae and later migrate to spawn grounds in the south (e.g., Atlantic cod Gadus morhua, Capelin Mallotus villosus, Beaked redfish Sebastes mentella). A total of 43 species from 15 families are known from FJL with the majority of the records from offshore trawl surveys between 110 and 620 m. Species endemic to the Arctic accounted for 75% of the nearshore species observed, followed by species with wider ranges. Including the tape-body pout, Gymnelus taeniatus, described earlier from the sub-littoral zone of Kuhn Island, 17 fish species are now known from FJL’s nearshore waters. 2 m in length, was recorded by drop camera near Hayes Island at 211 m, and Esipov’s pout, Gymnelus esipovi (Zoarcidae), was collected at Wilton Island at 15 m in a kelp forest. One Greenland shark, Somniosus microcephalus (Somniosidae), ca. Sixteen species of fishes from seven families were documented on the expedition, including two species previously unknown to the region. Due to its high latitude (79°–82°N), extensive ice cover, and low water temperatures (<0 ☌ much of the year), the fish diversity at FJL is low compared to other areas of the Barents Sea. In addition, deep water drop cameras were deployed between 32 and 392 m to document the fish fauna and their associated habitats at deeper depths. We present some of the first underwater images for many of these species in their natural habitats. An interdisciplinary expedition to FJL in summer 2013 used scuba, seines, and plankton nets to comprehensively study the nearshore fish fauna of the archipelago. The remote Franz Josef Land (FJL) Archipelago is the most northerly land in Eurasia and its fish fauna, particularly in nearshore habitats, has been poorly studied.
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