TY - JOUR
T1 - Experimental harvesting of Mytilus galloprovincialis
T2 - Can an alien mussel support a small-scale fishery?
AU - Robinson, Tamara B.
AU - Govender, Anesh
AU - Griffiths, Charles L.
AU - Branch, George M.
N1 - Funding Information:
We greatly appreciate funding from the National Research Foundation and Marine and Coastal Management through the Sea and the Coast Programme II, the Marine Biology Research Centre of the University of Cape Town, the Andrew Mellon Foundation and the Centre for Invasion Biology.
PY - 2007/12
Y1 - 2007/12
N2 - In an effort to stimulate new fisheries and address historic imbalances in access to fishing rights, there has been a recent focus on the development of small-scale fisheries in South Africa. To assess the biological viability of a fishery for the alien mussel Mytilus galloprovincialis, an experimental fishery operated by two impoverished coastal communities was initiated. Harvesting took place on a rotational basis at three sites, nested within four locations. At each of these 12 sites, 5 treatments were undertaken to span a spectrum of harvesting intensities (F = 0, 0.3, 0.6, 0.9 and a once-off total removal). A dynamic biomass-based fisheries model was developed to predict changes in exploited populations over time. Monthly maximum sustainable yield (MSY) estimates peaked at 1560 kg per 100 m of shore in March-April and September-October, but dropped by two orders of magnitude to 15 kg per 100 m of shore during the remainder of the year. The two peaks in MSY corresponded to the peak spawning periods of M. galloprovincialis along the South African west coast. Consequently, harvesting will only be viable if focused within two seasons spanning the peaks in MSY. Under these conditions, a range of harvesting intensities between F = 0.1 and 0.3 would permit long-term biological sustainability of a fishery. If implemented, this would represent the first instance of a marine invasive species being utilised to achieve socio-economic goals in South Africa.
AB - In an effort to stimulate new fisheries and address historic imbalances in access to fishing rights, there has been a recent focus on the development of small-scale fisheries in South Africa. To assess the biological viability of a fishery for the alien mussel Mytilus galloprovincialis, an experimental fishery operated by two impoverished coastal communities was initiated. Harvesting took place on a rotational basis at three sites, nested within four locations. At each of these 12 sites, 5 treatments were undertaken to span a spectrum of harvesting intensities (F = 0, 0.3, 0.6, 0.9 and a once-off total removal). A dynamic biomass-based fisheries model was developed to predict changes in exploited populations over time. Monthly maximum sustainable yield (MSY) estimates peaked at 1560 kg per 100 m of shore in March-April and September-October, but dropped by two orders of magnitude to 15 kg per 100 m of shore during the remainder of the year. The two peaks in MSY corresponded to the peak spawning periods of M. galloprovincialis along the South African west coast. Consequently, harvesting will only be viable if focused within two seasons spanning the peaks in MSY. Under these conditions, a range of harvesting intensities between F = 0.1 and 0.3 would permit long-term biological sustainability of a fishery. If implemented, this would represent the first instance of a marine invasive species being utilised to achieve socio-economic goals in South Africa.
KW - Alien
KW - Mytilus galloprovincialis
KW - Small-scale fishery
KW - Socio-economic development
KW - South Africa
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U2 - 10.1016/j.fishres.2007.07.005
DO - 10.1016/j.fishres.2007.07.005
M3 - Article
AN - SCOPUS:35748974199
SN - 0165-7836
VL - 88
SP - 33
EP - 41
JO - Fisheries Research
JF - Fisheries Research
IS - 1-3
ER -