Using life-history traits to predict the vulnerability to overexploitation in soldier striped shrimps

Abstract

The global overfishing scenario of the historically exploited marine stocks have generated concern and encouraged the search for new potentially exploitable fisheries resources. In this sense, shrimps are potential alternative resources to be exploited, given their high diversity and stock resilience. This study had an objective to estimate life-history traits and analyse yield and abundance fishing levels to see whether Plesionika edwardsii shrimp is vulnerable to overexploitation or not in the mid-North Atlantic (Azores region, ICES Subdivision 10a2). The females showed larger L∞ (asymptotic length) and k (coefficient of growth; L∞ = 27.3 mm, k = 0.75 year−1) than did males (L∞ = 24.58 mm, k = 0.73 year−1). The mortality rates of males (Z = 1.00 year−1; M = 0.84 year−1) and females (Z = 0.92 year−1; M = 0.85 year−1) were very similar. In terms of longevity, the males (3.47 year−1) survived longer than did females (3.34 year−1). Depletion experiments showed a fast and straight-forward decline of CPUEs (3, 5 and 9 days), confirming a low mobility and vulnerability to high fishing efforts. The maximum sustainable yield (MSY) estimates (5.4–10.7 tonnes (Mg) year−1) showed a low annual sustainable catch. These values combined with the life-history characteristics indicated that this stock is less resilient and highly vulnerable to overfishing.