Country: Brazil (South Brazil Bight)
Brazil is the largest South American country (8.5 million km2 of land size) with a coastal length of 8400 km, and 48% of its total population (196 million) living along the coast. The country is 19th in terms of global fish production with consumption increasing at 11 kg fish per capita - reaching 30 kg in the Amazon, and requiring 34% of its seafood products to be imported (MPA, 2014). Fisheries provide jobs for approximately 3.5 million people, and in terms of marine-dependent coastal communities, it is the main traditional activity and source of livelihood.
A particular focus is on the South Brazil Bight (SBB), contrasting to some selected sites across the diverse Brazilian coast with distinct ecosystem characteristics (e.g. coral reefs, mangroves) and social features. The SBB is a crescent-shaped marine ecosystem located between 23ºS 41'W and 28º S 48'W, in the Santos Basin at the northern end of the South Brazil Large Marine Ecosystem. It is considered a discrete biogeographic unit and is , adjacent to the most industrialized and urbanized coastal zone of the country. Consequently, there are several traditional fishing communities and industries that seem severely impacted by global changes such as pollution, tourism expansion, and overfishing.
The South Brazil Bight is characterized by isobaths that run almost parallel to the coastline with two seasonal features that boost primary productivity in the ecosystem: the South Atlantic Central Water (SACW) intrusion and Cabo Frio upwellings, as well as the occurrence of meso-scale eddies from the Brazil Current (to the east).
In the inner shelf, major oceanographic interactions occur among warm, saline, oligotrophic surface water (the so-called Tropical Water), low saline, productive coastal water highly influenced by river runoff and the seasonal wind-driven penetration of cold, nutrient-rich slope water (SACW) towards the coast. During the winter, the cold, low-salinity water from the La Plata River plume often influences the southern portion of the bight, through waters originating from the Malvinas current/Subtropical Convergence.
Economic and social context
The coastal areas of the South Brazil Bight sustain a diversity of economic activities being subject to increasing pressures such as urban development, industrial expansion, exploitation of natural resources, infrastructure, and tourism. Artisanal and industrial commercial fishing, tourism, shipping, and oil & gas exploration seem to be the most important economic activities while aquaculture is increasing slightly. Brazil has the second largest oil reserves in South America, where both the South Brazil Bight (Santos Basin) and the Campos basin hold the largest Brazilian gas fields.
Fishing communities are diverse and abundant, provide seafood and livelihoods to the country and have been impacted by recent developments as well as climate issues. Seafood consumption is increasing in the country (average 11 kg fish per capita), which is associated with the related social-economic progression and changing habits of the population.
The South Brazil Bight contributes about half of Brazil's commercial fisheries yields supporting important pelagic and demersal fisheries. The Brazilian sardine fisheries (Sardinella brasiliensis) are the most productive of Brazil which led to the development of an important purse-seine fishery, especially since 1950. Bottom trawling across the relatively smooth, sandy-mud bottom target mostly the shrimps Xiphopenaeus kroyeri (seabob shrimp) and Farfantepenaeus brasiliensis and F. paulensis (pink-shrimp), but also the white-mouth croaker Micropogonias furnieri, king weakfish Macrodon ancylodon, weakfish Cynoscion spp, and triggerfish Balistes capriscus. The pole-and-line based fishery for skipjack tuna (Katsuwonus pelamis) increased in the 1980s as a consequence of the regional expansion of industrial fisheries offshore.
Other fleets that operate in this region include longliners for tuna in oceanic zones and gillnetters in the shelf area. Overall, most fishing vessels operates in the shelf region, and those fisheries are mostly opportunistic multispecies fisheries. Loliginid squid (Doryteuthis spp), cutlass fish Trichiurus lepturus, the hake Merluccius hubbsi and rays are other important resources in coastal areas, as well as the mullets Mugil liza in estuarine zones, and the monkfish (Lophius gastrophysus) in deeper waters around 500m.
Biodiversity of the region
Brazil has the wealthiest biodiversity of the planet, but much of the marine biodiversity remains unknown. However, more than 13,000 marine species have been identified (about 10000 animals and 3000 plants). Mollusks and macro algae are amongst the most diverse (number of species) of South America. The Brazilian richness surpasses 3500 species of crustaceans and 2000 of mollusks.
All marine species inhabits a diverse set of habitats, from sandy and rocky coasts to mangroves, islands, seamounts and coral reefs. Generally, the demersal fauna is more abundant in depths less than 50m than at greater depths further offshore, and decapod crustaceans are important prey items for benthic fish species. So far, scientists have identified a total of 1520 fish species, 160 of which are cartilaginous (sharks and rays). Approximately 10.5% of reef fish species are endemic to Brazil.
In the SBB, penaeid shrimps, sardines, and sciaenid fish are quite dominant. Loliginid squid (Doryteuthis plei) are thought to play a key ecological role in the ecosystem as predators and prey, linking the pelagic and benthic sub-systems.
KEY Climate Concerns
• Sea surface temperature has increased by 1.12°C since 1957.
• Some shifts in the distributional range of commercially important species have observed, as well as ENSO events, flooding intensification, and heat waves. Coastal erosion resulting from climate driven shifts in coastal winds and wave patterns have affected people' livelihoods (e.g. home. infrastructure, resettlement, navigational routes and port access).
• Climate change models estimate a moderate decline in the future potential of capture fisheries in Brazil.
• In the South Brazil Bight, the rise in sea level, although small, may have potential consequences for accelerated coastal erosion, increased flooding, rising groundwater and increasing salinity in rivers, estuaries and aquifers.
• The changes associated with climate will act as additional sources of impact affecting the livelihoods of marine-dependent coastal communities.