Foe to friend: The potential commercial exploitation of the introduced macroalga Undaria pinnatifida in San Matias Gulf

Abstract

The study of introduced species often focuses on their ecological effects. In comparison, fewer studies explore thebenefits that people can obtain from these species. This study evaluated the seasonal variation in the populationcharacteristics of the introduced macroalga Undaria pinnatifida in the subtidal zone of San Matías Gulf (Patagonia,Argentina) and discussed the results considering the potential of its commercial exploitation as a fisheryresource. The population structure exhibited marked seasonality, with juvenile stages being more abundantduring austral autumn and winter. Maturing individuals appeared in late autumn to early winter, followed bymature individuals throughout spring, which senesced by summer. Peak biomass of 14769 ± 1083 g⋅m􀀀 2 anddensity of 38.1 ± 9.6 ind⋅m-􀀀 2 were registered during austral spring and summer, respectively. There is a potentialfor sporophyte harvesting (from late winter to late spring), with mean length of 1140 ± 60 mm, and meanwidth of 1088 ± 42 mm; and sporophyll harvesting from spring to mid-summer, with maximum mean lengthvalues of 185 ± 6.78 mm and mean width values of 55.4 ± 2.98 mm. Based on biomass and morphometriccharacteristics, our results suggest that U. pinnatifida could be exploited in the fishery industry of San MatíasGulf. Although further studies are needed in relation to market, quality and profitability of the product, thecommercial exploitation of U. pinnatifida may be an alternative fishery resource for the shellfish divers operatingin the gulf, reducing, the fishing pressure on the traditionally (over)exploited resources in San Matías Gulf.