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8 Fishery and Biological Implications of Fishing Spawning Aggregations…
Fig. 8.13 ( a , b ) Gulf corvina, Cynoscion othonopterus, aggregations are fi shed with 12.5 cm mesh
gillnets deployed from small boats that harvest up to 1 tonne of fi sh in a single net. Fisheries regulations allow only 1 net per boat. The commercial fi shery only takes fi sh during the time periods
when corvina migrate into the area to form aggregations and spawn in and near the estuaries during
the week preceding the new and full moons from late February to early May each year (i.e. 4–5
times); spawning months have been combined for the graph. Each fi shing period lasts 4–8 days,
with the majority of landings occurring at the exact days of spawning when fi sh are inside the estuary. During these days, the landings and CPUE ( dotted line ) are highest; percent females spawning
solid line (Photo: © Octavio Aburto/iLCP)
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CPUE (kg/boat)
Percentage of females spawning
Days before full or new moon