Spatial variability in size at maturity of golden king crab (Lithodes aequispinus) and implications for fisheries management

Abstract

Many crab fisheries around the world are managed by size, sex and season, where males are given at least one opportunity to reproduce before being harvested. Golden king crab (Lithodes aequispinus) supports a commercial fishery in Southeast Alaska and legal size is based on growth and maturity information from other parts of their range. Size-at-maturity estimates varied for crabs among seven management areas in Southeast Alaska, where male maturity estimates increased in size with increases in latitude, while maturity estimates across their North Pacific range decreased in size with increases in latitude. Depth, temperature and harvest history were not related to variation observed in male maturity estimates. Management implications from this research include reducing legal size in some areas to maximize harvest potential and increasing in others to allow male crabs the opportunity to reproduce before being harvested. A more conservative strategy would incorporate the largest maturity estimate, thus increasing the legal size which would have a negative impact to the commercial fishery, but allow male crabs the opportunity to reproduce before being harvested. This study shows the importance of understanding how life-history characteristics change over space and the challenge incorporating spatial variability for improved fisheries management.

Blue Crab Spawning and Recruitment in Two Gulf Coast and Two Atlantic Estuaries in Florida

“…The catch of female blue crabs was relatively consistent between years but fluctuated seasonally at all four sampling sites. Surprisingly, catch of immature, mature, and ovigerous females was seasonally dependent on coast rather than on latitude, with the latter being more common for marine crustaceans (Brante et al 2003;Olson et al 2018). St. Andrews Bay and Suwannee Sound had similar peaks in the number of ovigerous females during March-June and a subsequent peak in August-September.…”

HSP70 in Gills and Hepatopancreas of Mangrove Crabs Ucides cordatus: Comparison between Contaminated and Pristine Environments

“…Comparing the two areas (polluted and unpolluted), the animals present in the unpolluted area have greater weight and mean carapace width than animals in the polluted area. The presence of individuals with larger carapaces in the unpolluted area is evidence of the low fishing activity [22][23][24][25] and the environmental quality of the region, Regarding the posterior gills (Figure 1B), significant HSP70 levels were found in acclimatized animals from polluted environments compared to acclimatized animals from unpolluted environments (p = 0.049). In addition, an increase in HSP70 levels was also observed in acclimatized animals from polluted environments compared to field animals (p = 0.049).…”

Morphometric analysis of Harpodon nehereus, Harpiosquilla raphidea, and Scylla serrata in the coastal waters of Tarakan, North Kalimantan, Indonesia

“…Migratory species may also inhabit different places depending on their life stages. This influences the spatial distribution of species and so as the morphometric characteristics (Olson et al 2018). Spatial distribution can refer to horizontal or vertical movements, and in some migratory species, spatial variation occurs along with temporal variation (Arocha et al 2017).…”