Data from: Fishing pressure impacts the abundance gradient of European lobsters across the borders of a newly established marine protected area

Marine protected areas (MPAs) are considered as viable fisheries management tools due to their potential benefits of adult spillover and recruitment subsidy to nearby fisheries. However, before-after-control-impact (BACI) studies that explore the biological and fishery effects of MPAs to surrounding fisheries are scarce. We present results from a fine-scale spatial gradient study conducted before and after the implementation of a 5km2 lobster MPA in southern Norway. A significant non-linear response in lobster abundance, estimated as catch-per-unit-effort (CPUE) from experimental fishing, was detected within two years of protection. After 4 years, CPUE values inside the MPA had increased by a magnitude of 2.6 compared to before-protection values. CPUE showed a significant non-linear decline from the center of the MPA, with a depression immediately outside the border and a plateau in fished areas. Overall fishing pressure almost doubled over the course of the study. The highest increase in fishing pressure (by a magnitude of 3) was recorded within 1 km of the MPA border, providing a plausible cause for the depression in CPUE. Taken together, these results demonstrate the need to regulate fishing pressure in surrounding areas when MPAs are implemented as fishery management tools.