Anchorage areas, interference with Uruguayan fishing activities, and elements for marine spatial planning in the Río de la Plata

Abstract

Lightering and cargo transfer areas were defined in the Treaty of Río de la Plata in 1973, placing two on each side of the river. The increase of regional activity also increased the flow of goods, services, and fluvial and maritime transport. The growing number and size of transport vessels has led to the establishment of new anchorage zones rising from 236 km2 in 1977 to 600 km2 in 2014. Given that these zones are located in traditional fishing areas of the Uruguayan fishing fleet, the number of vessels, type and destination of vessels anchored in the various lightering and awaiting zones was evaluated along 6 months between 2017 and 2018, based on the data provided by the Automatic Identification System (AIS). It was found that the number of vessels anchored in these zones ranged 33 vessels each day, that there was a continuous vessels entry and exit, and that the residence time of each vessel was 3.6 days with a large dispersion of values. The most common type of ship was the Bulk Carrier, and the most frequent destinations were San Lorenzo and Rosario in Argentina. The higher activity in the deepest part of the river near the Uruguayan coast, where coastal fishing is carried out, contrasts with the scarce or null occupation of the lightering and cargo transfer areas near the coast of Argentina. The scope of this asymmetry is discussed and a revision of the space allocation in Rio de la Plata is suggested under the Treaty framework.