Movements of a potential fishery resource, porcupine crab (Neolithodes grimaldii) in Northern Davis Strait, Eastern Canadian Arctic

摘要

Climate change is positioning deep-sea lithodid crab species to expand their distributions. In Canada's Eastern Arctic, there is additional interest in the lithodid crab, Neolithodes grimaldii, (or porcupine crab) as a potential fisheries resource, as high biomass has been observed through incidental bycatch in the Greenland halibut (Reinhardtius hippoglossoides) fishery. This study aimed to advance our knowledge of the biology of the porcupine crab by addressing undescribed aspects of the crabs' spatiotemporal distribution. We administered pop-up archival tags (mrPATs and miniPATs) on 18 porcupine crabs and tracked their movements in Davis Strait at similar to 900 m depth. The tags were programmed to release sequentially, providing the location of a crab every six days across the study period (July-October 2018). Of the 18 tags, 17 (94%) successfully reported locations and six of those (35%) popped-off on the programmed date. A systematic method was established to estimate the most accurate final location of each crab, considering error introduced by tag drift (horizontal and vertical) and by satellite location accuracy. Six crabs (35%) moved between 3.1 and 33 km away from the deployment site over the course of 19 - 66 days, while the rest remained highly site attached moving <1 km. Crabs moved in a southern direction away from the deployment site; however, the broad range of this directional movement (113.6 degrees similar to 283.7 degrees), provides little support for coordinated group movement. Crabs also remained within a narrow depth and thermal range for the study period. To our knowledge, this study is the first to administer pop-up archival tags on porcupine crabs revealing a new technique to investigate their spatiotemporal movements. We propose further telemetry work to support the development of an offshore porcupine crab fishery in the Canadian Arctic.