Location and General Description
This ecoregion encompasses a number of discontinuous patches of mangroves associated with estuaries of small rivers. It extends from the region of the Recôncavo, State of Bahia, to the estuary of the River Doce, Espírito Santo. Major mangrove patches are found around Salvador, Maraú, Ilhéus, Canavieiras/Belmonte, Santa Cruz de Cabrália/Porto Seguro, Corumbaba, Alcobaça, Caravelas, and Conceição da Vitória. The climate all along this ecoregion is tropical humid without any dry months (Nimer 1979). Annual rainfall ranges from 1,750 to 2,115 mm. The annual average temperature varies from 24° to 26oC. Mangroves are found mostly behind the restingas.
The three genera of mangroves (Rhizophora, Avicennia, and Laguncularia) are found. Species such as Rhizophora mangle, Avicennia shaueriana, and Laguncularia racemosa compose mixed or mono-specific formations with heights varying from 5 to 15 m. The presence and abundance of the species vary from place-to-place according to the environmental conditions.
Biodiversity of the Bahia mangroves is still poorly investigated thus synthesis is not available. However, these mangroves play a critical role as both refuge and nursery for juvenile fishes, crabs, shrimps, and mollusks that all together are critical resources for local human populations, birds and mammals. Five sea turtles species (Caretta caretta, Chelonya midas, Dermochelys coriacea, Eretmochelys imbricata, and Lepidochelys olivacea) are found along this ecoregion and possibly use mangroves as feeding sites (Sanches 1999).
Birds, such as great egret (Casmerodius albus), snowy egret (Egretta thula), and little blue heron (Florida caerulea), are found nesting in large colonies on the mangroves. Migratory birds, such as semipalmated plover (Charadrius semipalmatus) and whimbrel (Numenius phaeopus) are found mostly from September through April, during their seasonal movements (Sick 1993). According to Stattersfield et al. (1998) the black-hooded antwren (Myrmotherula urosticta), Bahia tapaculo (Scytalopus psychopompus) and Dubois' seed-eater (Sporophila falcirostris) are just a few restricted range species that utilize the mangroves in this area. Because of their large distribution, Bahia mangroves are vital for the maintenance of ecological and evolutionary processes operating in a great part of the Brazilian coastal ecosystems.
Bahia mangroves are under strong human pressure, because some of their larger areas coincide with some of the more densely populated areas along the coast of northeastern Brazil. The most critical areas are those around Salvador and Ilhéus.Some protected areas were established along this ecoregion, but several of them have not been implemented and managed, allowing opportunities for continuing degradation.
Types and Severity of Threats
Urban expansion, timber exploration, and industrial pollution are the major factors that threaten Bahia mangroves. Despite these problems, there are still sufficient opportunities to plan and carry out an ecoregional plan that would conserve biodiversity and promote the sustainable use of the biological resources of the unique Bahia mangroves.
Justification of Ecoregion Delineation
Classification and linework for all mangrove ecoregions in Latin America and the Caribbean follow the results of a mangrove ecoregion workshop (1994) and subsequent report (Olson et al. 1996).
Ecoregional Workshop: A Conservation Assessment of Mangrove Ecoregions of Latin America and the Caribbean. 1994. Washington D.C., World Wildlife Fund.
Nimer, E. 1979. Climatologia do Brasil. Rio de Janeiro: IBGE/SUPREN.
Olson, D.M., E. Dinerstein, G. Cintrón, and P. Iolster. 1996. A conservation assessment of mangrove ecosystems of Latin America and the Caribbean. Final report for The Ford Foundation. World Wildlife Fund, Washington, D.C.
Sanches, T. M. 1999. Tartarugas Marinhas. Report presented to the Workshop "Biodiversidade da Zona Costeira e Marinha". http:// www.bdt.org.br/ workshop/ costa/tartaruga.
Sick, H. 1993. Birds in Brazil: a natural history. Princeton University Press, Princeton.
Spalding, Mark, Francois Nlasco and Colin Field.1997. World Mangrove Atlas. The International Society for Mangrove Ecosystems. Smith Settle, Otley, West Yrokshire, UK.
Stattersfield, Alison J., Michael J. Crosby, Adrian J. Long and David C. Wege. 1998. Endemic Bird Areas of the World: Priorities for Biodiversity Conservation. Birdlife International. The Burlington Press, Cambridge, UK.
Prepared by: Jose Maria C. da Silva
Reviewed by: In process