Stock-Recruitment-Environment Relationship in a Portunus pelagicus Fishery in Western Australia

Abstract

Blue swimmer crab (Portunus pelagicus) fisheries in Western Australia have generally been considered robust to recruitment overfishing, as the minimum legal size for retention of these crabs in both the commercial and recreational crab fisheries are set well above the size at sexual maturity allowing crabs to spawn at least once before entering the fishery. However, the Cockburn Sound crab stock suffered a recruitment collapse, with three key factors: (a) the fishery is near the edge of this species distribution and hence vulnerable to environmental fluctuations; (b) a number of consecutive years of poor environmental conditions resulted in poor recruitments; and (c) high fishing pressure continued on these low recruitments. This study indicates that water temperatures at the start of the spawning season positively influence the strong stock-recruitment relationship for P. pelagicus in Cockburn Sound. Apparently, warm water temperatures at the onset of spawning result in the larger females producing additional broods of eggs, and therefore a far greater number of larvae over the short spawning season. This relationship produces catch predictions for this fishery a year ahead and provides information for the development of biological reference points for management.

The relationship between blue swimming crab (Portunus pelagicus) abundance and environmental parameters in Spermonde Archipelago

“…The development of ovaries and eggs in the blue swimming crab is strongly controlled by temperature. Even water temperature was being the only factor that can influence the life cycle and the change of population structure for a long period (De Lestang et al, 2003;De Lestang et al, 2010). Also, the temperature of the blue swimming crab can growth is 25-32 ºC (Romano & Zeng, 2008).…”

Influencia de la proporción sexual y del ambiente en la tasa de crecimiento poblacional de Callinectes bellicosus (Decapoda: Portunidae) del Golfo de California

“…Los datos y los análisis indicaron que los humedales son importantes para los stocks de jaiba porque H/M y SH se relacionan directamente con r. El stock de la zona 3 tiene la mayor r, la mayor H/M y la mayor SH. Esto puede indicar que la producción de huevos aumenta con la abundancia de hembras (Lasker, 1985) y la abundancia de humedales favorece el reclutamiento (Carmona, 2009;De Lestang et al, 2010;Fischer & Wolff, 2006). Dada la importancia de este posible hallazgo, en el futuro se deben incorporar mayor cantidad de datos para mejorar el análisis de sensibilidad.…”

Association of Environmental Factors in the Taiwan Strait with Distributions and Habitat Characteristics of Three Swimming Crabs

“…For P. pelagicus, BT explained considerable variance and had negative correlations with BTs >25 • C in the TS. Studies have revealed that the water temperature is a factor that controls the ovarian development and spawning of P. pelagicus [10,24,58]. Moreover, Qari and Aljarari [58] mentioned that temperature is a critical environmental parameter that plays a role in limiting the distribution and activity of P. pelagicus in the Red Sea.…”

“…This information can be used to implement sustainable fisheries through methods, such as harvest strategy planning [1], ecosystem management [2,3], spatial management [4][5][6], and bycatch reduction [7]. Environmental variables, such as water temperature, salinity, water depth, and increased productivity, may be significant factors driving changes in population patterns [8,9], catch rates [10][11][12], reproductive and recruitment strategies [13][14][15], and spatiotemporal distribution [16,17].…”