Present state and perspectives for the southern Brazil shelf demersal fisheries

Abstract

The demersal fish stocks in southern Brazil were assessed from landings and catchper‐unit effort data trends between 1975 and 1994, available information on the life history patterns, and population dynamics of the most important species. The fishing gears, mostly otter and pair bottom trawls in the 1970s, diversified towards double‐rig trawls for fish and shrimp and bottom gill nets in the mid 1980s, and bottom longlines in the upper slope in the early 1990s. There were also some less successful attempts with traps for fish and crabs. The demersal fisheries are more intensive in winter when migratory species move northward, associated with the seasonal displacement of the western boundary of the Subtropical Convergence. Landings between 1975 and 1994 were mostly of sciaenid fishes (>70%) and elasmobranchs (10%) and oscillated around 59 000 t. There was not a decrease in total landings but a shift from more to less exploited stocks. Since 1989, 4% of the landings came from depleted stocks of Pagrus pagrus (L.), Netuma barba (Lacépède), Pogonias cromis (L.) and Rhinobatos horkelli (Muller & Henle); 37% from overexploited stocks: Micropogonias furnieri (Desmarest), Paralichthys patagonicus Jordan, Squatina guggenheim Marini, and Galeorhinus galeus (L.); 24% from heavily exploited stocks of Umbrina canosai Berg, and Macrodon ancylodon (Bloch & Schneider); and 35% of Cynoscion guatucupa (Cuvier) and small stocks with unclear status. The demersal fisheries are virtually unmanaged and future landings are expected to decrease if fishing pressure remains high. Effective management will require the participation of all three countries in the region because most of the stocks fished in southern Brazil are shared with Uruguay and Argentina.

Trophic relationships between people and resources: fish consumption in an artisanal fishers neighborhood in Southern Brazil

“…In addition to this information, diagnostic data for fishing in Santa Catarina (Santa Catarina 2004) show that these species are among the primarily exploited species by the artisanal fleet in the state. These species are being overfished in a biologically unsustainable manner, due to the pace and intensity of fishing activity on these resources throughout the southern region (Haimovici 1998;Vasconcellos et al 2007). All these findings call attention to the ongoing process of change in the livelihood and subsistence of all coastal communities that generates a gradual reduction in the perceived availability of fish for these populations.…”

Assessment of the conservation status of a franciscana (<i>Pontoporia blainvillei</i>) stock in the Franciscana Management Area III following the IUCN Red List Process

“…Two important prey species of franciscana (the sciaenids Micropogonias furnieri and Macrodon ancylodon) have been exploited heavily and are currently at very low levels in southern Brazil (Haimovici et al, 1997;Haimovici, 1998). This coincides with a large reduction in the occurrence of these two species in the diet of franciscana of this region.…”

“…In contrast, the frequency of occurrence of the cutlassfish, Trichiurus lepturus, and another sciaenid, Umbrina canosai, in the diet of the franciscana has increased from about 5% to 39% and from about 3% to 20%, respectively, between the late 1970s and the mid 1990s. T. lepturus and Cynoscion guatucupa represent 47% of the total estimated bony fish biomass in this region (Haimovici et al, 1996) but these species have only experienced moderate fishing pressure (Haimovici et al, 1997;Haimovici, 1998). The latter species has always been the most important prey for franciscana but T. lepturus was only of minor importance in the past.…”

Variation in the isotopic composition of striped weakfish Cynoscion guatucupa of the Southwest Atlantic Ocean in response to dietary shifts

“…The striped weakfish Cynoscion guatucupa (Cuvier 1830) inhabits coastal bottom waters from Río de Janeiro, Brazil (22° S) to Chubut, Argentina (43° S) (Haimovici, 1998;Cousseau and Perrotta, 2000) and is one of the most important coastal fishery resources of Argentina, Brazil and Uruguay (Haimovici, 1998;Jaureguizar et al, 2006;Ruarte and Aubone, 2008).…”