New perspectives on the growth and longevity of the European lobster (Homarus gammarus)

Abstract

The natural rate of lipofuscin accumulation in an eyestalk ganglion was determined from microtagged European lobsters, Homarus gammarus, of known age, recaptured from the Yorkshire fishery (United Kingdom). This calibration, in combination with supporting data from shorter-lived astacideans (freshwater crayfish), was used to age wild lobsters from the fishery. A unique perspective of age-at-size in a clawed-lobster population was obtained, which circumvented some difficulties associated with conventional methods for estimating generalized growth and natural mortality. The exceptional ages attained by some of the largest lobsters (males: average 31 years, maximum 42 ± 5 years; females: average 54 years, maximum 72 ± 9 years) are explained by ageing theory, indicate natural mortality rates, M, of 0.15 and 0.08 for males and females, respectively, and point to the existence of an offshore refuge. Age-at-size is highly variable: at least seven year-classes enter the fishery at 85 mm carapace length. This limits resolution of annual cohorts in size compositions, complicates development of recruitment indices, and may explain past size composition stability. The new age-length data suggest potential selective fishing impacts and past early recruitment variations. The study highlights the need for age data in order to obtain accurate crustacean stock assessments.

Long-term decrease in sex-specific natural mortality of European lobster within a marine protected area

“…European lobster longevity may potentially span several decades, during which large specimens may grow to weights up to 10 kg. Average age of large (150 to 170 mm carapace length, CL) male and female specimens has been estimated as high as 31 and 54 yr, respectively, based on accumulation of lipofuscin in the eyestalk ganglion (Sheehy et al 1999). The same study estimated that the 80-89.9 mm CL size class contained males that were 3.5 to 12.9 yr old and females that were 4.1 to 13.0 yr old.…”

Survivorship of juvenile surf clams Donax serra (Bivalvia, Donacidae) exposed to severe hypoxia and hydrogen sulphide

“…Only a few findings are reported from clams so far: In the alimentary tract epithelium, in gonadal connective tissue and in the renal epithelium of Mya arenaria and Mercenaria mercenaria (Brown and O'Toole, 1978); in the digestive gland of Ruditapes phillipinarum (Sarasquete et al, 1992) and of Sunetta scripta (Mathew and Damodaran, 1997); and in the kidney of Tridacna gigas (Reid et al, 1984). As in E. exalbida, these are all tissues containing mitotic cells, which is in contrast to crustaceans, insects and vertebrates, where lipofuscin seems to be concentrated in postmitotic cell tissues such as nerves (Hammer and Braum, 1988;Sheehy et al, 1999;Bluhm and Brey, 2001).…”

“…Hence, the amount of lipofuscin may be proportional to physiological age and can be suitable as a proxy of chronological age, too, as shown in many studies on crustaceans (e.g. Sheehy, 1992;Sheehy et al, 1995Sheehy et al, , 1999O'Donovan and Tully, 1996;Wahle et al, 1996;Belchier et al, 1998;Bluhm and Brey, 2001). Molluscs studies of lipofuscin in situ have focused primarily on the effect of stress such as exposure to heavy metals or anoxic conditions (e.g.…”

Direct and Indirect Estimates of Natural Mortality for Chesapeake Bay Blue Crab

“…Annala (1977) presented some direct estimates for southern rock lobster Jasus edwardsii in New Zealand, and Thomas (1973) and Anthony (1980) reviewed both direct and indirect estimates of M for American lobster Homarus americanus. Additional studies of lobsters (Sheehy et al 1999;French McCay et al 2003) and other exploited crustaceans (Gabche and Hockey 1995) have used indirect methods to predict M based on the correlation between mortality and other life history parameters. This indirect approach is also common to fish stock assessments (Vetter 1988;Quinn and Deriso 1999).…”