INFLUENCE OF WIND, BEHAVIOR AND CHARACTERISTICS OF THE CROAKER (MICROPOGONIAS-FURNIERI) ARTISANAL FISHERY IN THE RIO-DE-LA-PLATA (URUGUAY)

This study of the croacker artisanal fishery in Uruguay analyses the characteristics of the fishery, the action of the winds in relation to the fishing activity, and the behaviour of the fishermen in a fishing season. The activity of the fleet during the fishing season is irregular, with alternating periods of high and low or zero activity. The target species (Micropogonias furnieri; Pisces: Sciaenidae) is traditionally located by the fishermen by tasting the salinity of the bottom water, and is caught by the use of either the bottom-set-longline or the gillnet. In the fishing season (summer) the post-frontal period is short, the winds are less strong and turn rapidly from south-southeast to east-northeast and the weather tends to be stable. Fishing activity is greatest when winds are from the east-northeast sectors. These winds favour deep intrusion of salt water into the estuary, when the post-frontal period, which occurs after the wind has blown from the southeast, has finished. Maximum CPUE was recorded with winds of a daily average speed of 10 km h-1 and maximum averages of 16 km h-1. The independence between the catch rate and effort suggests that the fishermen acted as ideal free predators. Although the activity of the fishery is concentrated in the most advantageous periods for catching the target species (October to March), the meteorological conditions (winds), the regularity of the activity, the knowledge of detecting the resource and its availability in the fishing ground are most likely to determine the profit per boat and its variance.