Management boundaries that define populations or stocks of fish form the basis of fisheries planning. In the Arctic, decreasing sea ice extent is driving increasing fisheries development, highlighting the need for ecological data to inform management. In Cumberland Sound, southwest Baffin Island, an indigenous community fishery was established in 1987 targeting Greenland halibut (Reinhardtius hippoglossoides) through the ice. Following its development, the Cumberland Sound Management Boundary (CSMB) was designated and a total allowable catch (TAC) assigned to the fishery. The CSMB was based on a sink population of Greenland halibut resident in the northern section of the Sound. Recent fishing activities south of the CSMB, however, raised concerns over fish residency, the effectiveness of the CSMB and the sustainability of the community-based winter fishery. Through acoustic telemetry monitoring at depths between 400 and 1200 m, and environmental and fisheries data, this study examined the movement patterns of Greenland halibut relative to the CSMB, the biotic and abiotic factors driving fish movement and the dynamics of the winter fishery. Greenland halibut undertook clear seasonal movements between the southern and northern regions of the Sound driven by temperature, dissolved oxygen, and sea ice cover with most fish crossing the CSMB on an annual basis. Over the lifespan of the fishery, landfast ice cover initially declined and then became variable, limiting accessibility to favored fisher locations. Concomitantly, catch per unit effort declined, reflecting the effect of changing ice conditions on the location and effort of the fishery. Ultimately, these telemetry data revealed that fishers now target less productive sites outside of their favored areas and, with continued decreases in ice, the winter fishery might cease to exist. In addition, these novel telemetry data revealed that the CSMB is ineffective and led to its relocation to the entrance of the Sound in 2014. The community fishery can now develop an open-water fishery in addition to the winter fishery to exploit the TAC, which will ensure the longevity of the fishery under projected climate-change scenarios. Telemetry shows great promise as a tool for understanding deep-water species and for directly informing fisheries management of these ecosystems that are inherently complex to study.

Little is known about the movement of Arctic marine fish, particularly benthic species, despite growing pressure from commercial fisheries and a changing climate. The Greenland halibut Reinhardtius hippoglossoides lives in the deep, cold waters of the Arctic, North Atlantic and Pacific Oceans where it represents an important commercial fish species and a significant prey resource for whales and sharks. To investigate movement, depth and temperature preferences of Greenland halibut, 9 large (83 to 95 cm fork length) individuals were tagged with pop-off archival transmitting tags in Cumberland Sound, Baffin Island in August 2010 to record data for 70, 100 and 300 d. While all tags reported back, 7 tags provided the bulk of the data, transmitting (mean ± SD) 67 ± 7% of the data collected. Greenland halibut exhibited strong site fidelity to localised deep areas (900 to 1400 m), but ranged between ~400 and 1400 m, with all tags poppingoff within 27 km of the tagging location. Mean depth was 1048 ± 112 m (n = 7) during the ice-free season and 823 ± 121 m (n = 2) during the ice-covered season. Temperature occupied by Greenland halibut from August until June ranged from 1.3 to 2.7°C (mean ± SD: 2.2 ± 0.01°C). A mixedeffect model found preferred depth did not vary within a diel cycle, but did change among months. Seasonal movements coincided with ice cover, but further work is needed to clarify this relationship and determine the extent and timing of these movements within and beyond Cumberland Sound. KEY WORDS: Arctic · Movement patterns · Archival tags · Marine fish · Depth preferences · Sea iceResale or republication not permitted without written consent of the publisher Mar Ecol Prog Ser 467: 193-205, 2012 marine fishes, e.g. distribution and maturation of larvae (Gibson 1997, Sohn et al. 2010. Understanding how the characteristics of Arctic marine ecosystems relate to fish movement patterns (i.e. linking environmental parameters with the distribution and abundance of fishing resources) is of critical importance for the management and conservation of Arctic marine fish stocks (Schick et al. 2008).Satellite telemetry has been used to study the movement, behaviour and environmental preferences of a wide range of aquatic species, including sharks (Sims et al. 2003, 2008, Teo et al. 2004, Brunnschweiler et al. 2010) and many teleostei, such as tuna (Block et al. 2001, Kitagawa et al. 2004, Schaefer & Fuller 2004 and flatfishes (Seitz et al. 2003, Loher & Seitz 2006, Loher & Blood 2009). These tags are attached externally to the fish, during which time they record depth, temperature and light, and release after a specified length of time, thus providing insight into horizontal and vertical movements and habitat use over different spatial and temporal scales (Block et al. 2001, Wearmouth & Sims 2009, Humphries et al. 2010. There is no requirement to recapture tagged individuals, making this technology particularly useful for studying fish in deepwater habitats and extreme environments, such as the Arctic, wher...

Climate change and increasing exploitation of resources are threats to Arctic marine species. Knowledge of vertical and horizontal movements of species is critical to understand their spatial ecology to inform effective ecosystem-based management. Recently, Arctic skate Am blyraja hyperborea, a largely unstudied, cold water, deep-dwelling species has become a common bycatch species in groundfish fisheries throughout the Arctic. To investigate Arctic skate movement, depth and temperature preferences, 9 adults were tagged with pop-off archival transmitting tags in Cumberland Sound, Canadian Arctic, in August 2010 and August 2011 for 40 to 100 d. Of the 9 individuals tagged, 5 transmitted reliable data to satellites. Arctic skate occupied waters between 1.2 and 2.9°C (2.5 ± 0.1°C; mean ± SD) and 317 and 1355 m (944 ± 154 m). Tags popped off within a 37 km straight-line distance from the tagging location, indicating limited horizontal dispersal during the pre-ice formation period of late summer and early winter. Although mixedeffect models indicated that occupied depth varied with the diel cycle, the relationship was weak and depth variation was small, suggesting diel vertical migration does not appear to be a common strategy. Activity levels, estimated from detailed time series depth profiles, indicated multiple behaviours from resting to large depth changes (>150 m per 0.5 h). Given the levels of bycatch of this species in developing Arctic fisheries, overlap in habitat with the commercially valuable Greenland halibut Reinhardtius hippoglossoides and historical declines of skate populations, it is recommended that the IUCN Red List designation of 'Least Concern' for the Arctic skate be re-evaluated. KEY WORDS: Arctic · Bycatch · Fisheries · Movement · Archival tags · Rajidae Resale or republication not permitted without written consent of the publisherEndang Species Res 23: [229][230][231][232][233][234][235][236][237][238][239][240] 2014 actions. Spatial data are also important for elucidating how environmental parameters affect species dispersal, abundance and movement (Schick et al. 2008), especially given changing sea ice conditions. Pop-off archival transmitting (PAT) tags have been widely used to quantify behavioural movement patterns in relation to environmental conditions in a wide range of marine species that are typically difficult to observe (e.g. Sims et al. 2003, Hunter et al. 2004a, Block et al. 2005, Wearmouth & Sims 2009). Specifically, PAT tags collect light level data that provide geolocation estimates; high-resolution timeseries depth data to describe vertical movements, water column use and behavioural patterns; and environmental data such as depth−temperature profiles to quantify the range of preferred environmental conditions (e.g. Seitz et al. 2003, Sims et al. 2003, Loher 2008. Despite their common application in tropical and temperate climates, the use of PAT tags to study fish in polar ecosystems has been limited , Peklova et al. 2012.Arctic skate Amblyraja hyperborea are mid...