Female reproductive output and potential recruitment of three fished southern king crab stocks from the Southern Atlantic Ocean

The female reproductive output and potential recruitment (PR) were studied in three Argentinean southern king crab (Lithodes santolla and Lithodes confundens) stocks: in the Beagle Channel (BC), under an artisanal fishery pressure since 1930; in the San Jorge Gulf (SJG), under 10years industrial fishing exploitation; and off the Atlantic coast of Isla Grande de Tierra del Fuego (TDF), under current exploratory regime. After evaluating their reproductive parameters, we suggest that these fisheries pass through at least two detectable phases. The first phase, in the SJG stock, is sperm limitation evidenced by a high proportion of ovigerous females but a decreased female fecundity. A second phase, in the BC stock, shows a sustained low proportion of ovigerous females which were the largest females of this stock, along with a decreased relative abundance, which in lithodids are indicators of recruitment overfishing. Contrastingly, the TDF stock showed healthy population parameters before the opening of the exploratory fishery. The extremely low value of PR (2.6%) in the BC stock further reinforces that this stock is experiencing or has experienced recruitment overfishing, as a small proportion of the offspring would reach sexual maturity or achieve legal sizes.

Automated summary

The study shows that different stocks of Argentinean southern king crab are affected by fisheries in different phases, including sperm limitation and recruitment overfishing. The Beagle Channel stock is experiencing recruitment overfishing, while the San Jorge Gulf stock shows sperm limitation. The stock off the Atlantic coast of Isla Grande de Tierra del Fuego exhibited healthy population parameters before exploratory fishing.