|dc.contributor.author||Kleiven, Portia Joy Nillos||
|dc.description||Master's thesis Aquatic Ecology BIO500 - University of Agder 2017||nb_NO
|dc.description.abstract||Marine protected areas (MPAs) are valued for their conservation benefits to harvested
species. However, potential benefits of MPAs to neighboring fisheries are less well-understood.
This study quantifies how the European lobster (Homarus gammarus) and the fishery for this
valued catch respond to the establishment of a relatively small (5.2 km2) MPA on the
Norwegian Skagerrak coast. A series of yearly standardized trap surveys was conducted to
estimate lobster abundance and catch weights both inside and outside the MPA before (2010-
2011) and after the MPA was established (2012-2016). Lobster abundance and catch weights
were determined as number of catch per unit effort (CPUEN) and weight of catch per unit effort
(CPUEw), respectively. Using a similar before-after study design, the lobster fishery was
described from fishery diaries and by counting all lobster traps in the study area.
After 4 years of protection, gradients for abundance and catch weights across the MPA
boundaries have developed, but the export of benefits to neighboring fishing areas are limited.
Inside the MPA, CPUEN values increased from 0.748 lobsters/trap/day before protection to 1.93
lobsters/trap/day after protection. Catch weights have also increased from 1.29 kg/trap/day to
1.54 kg/trap/day in the same period. Slight increases in CPUEw were observed in the fished
areas near the boundary, but not for CPUEN. At fished areas 2-3 km away from the boundaries,
CPUEN values were stable, and catch weights have increased. This suggests that fishers around
the MPA are catching larger, but not more lobsters around the MPA. Increased catch weights
in the fished areas are attributed to the protection of berried female lobsters from fishing
mortality. Fishing pressure, mostly from recreational fishers, is increasing the most outside
MPA boundaries, resulting in lowered CPUEN and catch weight values. Results from the study
indicate that determining conservation and fishery benefits of an MPA should always be
considered in context of existing and changing fishing pressure in order to effectively utilize
MPAs as a fishery management tool.
Keywords: European lobster, Homarus gammarus, MPA benefits to fisheries, lobster CPUE,
|dc.publisher||Universitetet i Agder ; University of Agder||nb_NO
|dc.rights||Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal||*
|dc.subject||MPA benefits to fisheries||nb_NO
|dc.title||Responses of European lobster (Homarus gammarus) and lobster fishers to protective management||nb_NO
|dc.subject.nsi||VDP::Landbruks- og Fiskerifag: 900::Fiskerifag: 920::Ressursbiologi: 921||nb_NO