Natural mortality and longevity of the burrowing crayfish Parastacus pugnax (Poeppig, 1835) (Decapoda: Astacidea: Parastacidae)

Information about longevity and mortality of decapod crustaceans is scarce but is of utmost importance for our understanding of the dynamics of exploited populations. Moreover, such information is crucial for the development of conservation and management strategies. Compared to other crustacean taxa, crayfishes are understudied and under increasing threat of extinction. Particularly, life history data for burrowing crayfishes is highly limited, which is related to their subterranean habitat and collection difficulty. Considering the limited knowledge on mortality and life span in burrowing crayfishes, we studied these two parameters in the burrowing crayfish Parastacus pugnax (), one of six species of Parastacidae in Chile. This species inhabits subterraneous waters in semi-swampy terrain and is heavily exploited for human consumption. We calculated longevity (A(0.95)) and natural mortality (M) of this species, using growth estimates published in the literature. Longevity was estimated to vary between 8.2 and 12.4 yr. The estimated values for M ranged from 0.241 to 0.611 yr(-1), and the medium for the population ranged from 0.37 to 0.57 yr(-1). Compared to other crayfishes, parastacids are generally classified as longer-living species, and some can live for decades. Our results suggest that P. pugnax is a medium-age species with a medium-range mortality compared to other parastacids.

Automated summary

Information about longevity and mortality of decapod crustaceans, especially crayfishes, is limited but crucial for understanding the dynamics of exploited populations. In this study, we estimated the longevity and natural mortality of the burrowing crayfish Parastacus pugnax in Chile, finding a lifespan range of 8.2 to 12.4 years and a mortality rate of 0.241 to 0.611 per year.