Demographic responses to protection from harvesting in a long-lived marine species

Marine protected areas (MPAs) are usually considered to have positive effects on the recovery of over-exploited populations. However, resolving extent which MPAs function according their conservation goals requires that essential demographic information such as individual survival and population size quantified. To this end, we analyzed a 16-year replicated mark-recapture study European lobster (Homarus gammarus, n = 8793) conducted at several unprotected sites in southern Norway, quantifying impact local dynamics by means “before-after control-impact” approach (BACI). Lobster abundance were estimated applying multi-state robust design models data. These revealed underlying responses protection. Annual rates abundances reached higher values MPAs, compared (abundance range: 96–1172, control 92–747). In general, female was than male (range survival: 0.13–0.75, 0.37–0.85), while larger males benefited more from protection smaller increase after protection: big 100–125%, small 55–101%). We also detected regional differences protection, not all showed same changes over time. Our results show can reach increasing lobster, but they highlight between sexes geographic worth considering for management both current future MPAs.