Abrolhos Bank IMMA

Size in Square Kilometres

60 378 km2

Qualifying Species and Criteria

Humpback Whale – Megaptera novaeangliae

Criterion B(2); C (1)

Guiana Dolphin – Sotalia guianensis

Criterion B (1)

Marine Mammal Diversity 

Criterion D (1)

Sotalia guianensis

Criterion D (2)

Megaptera novaeangliae, Sotalia guianensis, Pontoporia blainvillei, Eubalaena australis, Steno bredanensis, Tursiops truncatus truncatus, Balaenoptera edeni, Balaenoptera acutorostrata, Balaenoptera bonaerensis, Pseudorca crassidens, Feresa attenuata, Peponocephala electra, Grampus griseus, Stenella frontalis, Stenella attenuata, Stenella longirostris

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Located in North-eastern Brazil, the Abrolhos and Royal Charlotte Banks comprise the largest coral reef environment in the South Atlantic, with associated coastal mangrove forests and estuaries. Its shallow (mostly less than 50 m) waters harbour between June and November the largest breeding and calving aggregation of humpback whales (Megaptera novaeangliae) in the Western South Atlantic, as well as the only known offshore population of Guiana dolphins (Sotalia guianensis). At least 16 cetacean species occur in the Bank, including Southern Right whales (Eubalaena australis), Rough-toothed dolphins (Steno bredanensis) and three species of the oceanic dolphin genus Stenella (S. attenuata, S. frontalis and S. longirostris).

Description of Qualifying Criteria

Criterion B: Distribution and Abundance

Sub-criterion B1: Small and Resident Populations

The area fulfils sub-criterion B1 due to the presence of a resident populations of Guiana dolphins (Rossi-Santos et al., 2006; Rossi-Santos et al., 2007). The population of Guiana dolphins in the Caravelas River estuary, eastern Brazil, was systematically monitored through a long-term mark-recapture study (2002–2021). Abundance estimates revealed a small population (57–124 dolphins), which include a portion of long-term residents (Cantor et al., 2012). For other areas of the IMMA there is less information about the size of the population.

Sub-criterion B2: Aggregations

The area fulfils sub-criterion B2 as the main breeding ground of the Humpback Whale in the Western South Atlantic (Andriolo et al., 2010; Martins et al., 2013).  The last abundance estimate of humpback whales within the Abrolhos Bank, from a distance sampling aerial survey conducted in 2019, was 9,206 whales (CI95% = 5.135 – 16.505; CV% = 29,3), which correspond to 63% of the total abundance estimated for the Brazilian coast.

Criterion C: Key Life Cycle Activities

Sub-criterion C1: Reproductive Areas

The sub-criterion C1 is applied as the IMMA is important breeding and calving grounds for Humpback whales. The warm waters and wide extension of shallow habitats, with the presence of coral reefs and an archipelago constitutes typical breeding habitats of the species. The whales are present between July and November. Morete et al. (2008) describe temporal changes in the relative abundance of humpback whales around Abrolhos archipelago, over seven years (1998–2004).  Whale count data were collected during July through to November and during one-hour-scans, observers determined group size within 9.3 km (5 n.m.) of a land-based observing station. A total of 930 scans, generated 7996 sightings of adults and 2044 calves. Competitive groups are also abundant in Abrolhos Bank (Martins et al., 2001), as well as intense male singing activity (Sousa-Lima & Clark, 2008).

Criterion D: Special Attributes

Sub-criterion D1: Distinctiveness

Guiana dolphins, a habitat specialist of estuarine and coastal environments (Lobo et al., 2021), have their only known offshore population in the Abrolhos Bank IMMA. Guiana dolphins are found living more than 70 kilometers from the coast in a coral reef environment (Borobia et al., 1991; Rossi-Santos et al. 2006).

Sub-criterion D2: Diversity

The area fulfils sub-criterion D2 as the habitat is regularly used by at least 16 cetacean species (Andriolo et al, 2010; Danilewicz et al., 2013; IBJ, 2012; Moreno et al., 2003; Nara et al., 2022; Rossi-Santos et al., 2006; Wedekin et al., 2009).

Supporting Information

Andriolo, A.; Kinas, P.G.; Engel, M.H.; Martins, C.C.A.; Rufino, A.M. 2010. Humpback whales within the Brazilian breeding ground: distribution and population size estimate. Endangered Species Research 11: 233–243

Bezamat, C.; Wedekin, L.L. & Simões-Lopes, P.C. 2015.Potential ship strikes and density of humpback whales in the Abrolhos Bank breeding ground, Brazil. Aquatic Conservation: Marine and Freshwater Ecosystems. 25, 712-725

Bornatowsky, H.; Wedekin, L.L.; Heithaus, M.R.; Marcondes, M.C.C. & Rossi-Santos, M.R. 2012. Shark scavenging and predation on cetaceans at Abrolhos Bank, eastern Brazil. Journal of the Marine Biological Association of the United Kingdom. 92(8), 1767-1772

Borobia, M., Siciliano, S., Lodi, L.F. & Hoek, W. 1991. Distribution of the South-American dolphin Sotalia fluviatilis. Canadian Journal of Zoology. 69, 1025–1039

Brasil. Ministério do Meio Ambiente. 2022. Portaria MMA 148 de 07 de junho de 2022.

Cantor, M.; Wedekin, L.L.; Daura-Jorge, F.G.; Rossi-Santos, M.R. & Simões-Lopes, P.C. 2012.Assessing population parameters and trends of Guiana dolphins (Sotalia guianensis): An eight-year mark-recapture study. Marine Mammal Science. 28 (1), 63-83

Danilewicz, D., Ott, P. H., Secchi, E., Andriolo, A., & Zerbini, A. 2013. Occurrence of the Atlantic spotted dolphin, Stenella frontalis, in southern Abrolhos Bank, Brazil. Marine Biodiversity Records, 6. https://doi.org/10.1017/S1755267212000929

Díaz-Delgado, J.; Groch, K.R.; Ramos, H.G.C.; Colosio, A.C.; Alves, B.F.; Pena, H.F.J. And Catão-Dias, J.L. 2020. Fatal Systemic Toxoplasmosis by a Novel Non-archetypal Toxoplasma gondii in a Bryde’s Whale (Balaenoptera edeni). Frontiers in Marine Science 7:336. doi:10.3389/fmars.2020.00336 

Dutra, G.F., G.R. Allen, T. Werner, and S. A. Mckenna (Eds.). 2005. A Rapid Marine Biodiversity Assessment of the Abrolhos Bank, Bahia, Brazil. RAP Bulletin of Biological Assessment 38. Conservation International, Washington, DC, USA.

Engel, M.H.; Freitas, Ac.S.; Skaf, M.K. et al. 1997 . Ocorrencia de baleias franca Eubalaena australis em área de reprodução da baleia jubarte Megaptera novaeangliae no Banco dos Abrolhos, Bahia. Resumos do XI Encontro de zoologia do Nordeste, Fortaleza, 1997, p 78. 

Groch, K. R.; Colosio, A.C.; Marcondes, M.C.C.; Zucca, D.; Diáz-Delgado, J.; Niemeyer, C.; Marigo, J.; Brandão, P.E.; Fernandez, A. & Catão-Dias, J.L.2014.Novel Cetacean Morbillivirus in Guiana Dolphin, Brazil. Emerging Infectious Diseases.20, 511-513

Groch, K.R.; Blazquez, D.N.H.; Marcondes, M.C.C.; Santos, J.; Colosio, A.; Diaz-Delgado, J. And Catão-Dias, J.L. 2020. Cetacean Morbilivirus in Humpback Whale’s Exhaled Breath. Transboundary Emerging Diseases 2021; 68:1736–1743. https://doi.org/10.1111/tbed.138831-8

IBJ 2012. Projeto de Monitoramento de Cetáceos nos Campos Peroá e Cangoá – Relatório Final, Janeiro 2007 – Dezembro 2011, L.O. IBAMA 823/2009.

Lobo, A.J., Wedekin, L.L., Sobral-Souza, T. & Le Pendu, Y. 2021. Potential distribution of Guiana dolphin (Sotalia guianensis): a coastal-estuarine and tropical habitat specialist. Journal of Mammalogy. 102(1), 308-318

Martins, C.C.A.; Morete, M.E.; Engel, M.H.; Freitas, A.C.; Secchi, E.R. & Kinas, P.G.2001.Aspects of habitat use patterns of humpback whales in the Abrolhos Bank, Brazil, Breeding Ground. Memoirs of the Queensland Museum.47(2) 563-570

Martins, C.C.A.; Andriolo, A.; Engel, M.H.; Kinas, P.G. & Saito, C.H. 2013. Identifying priority areas for humpback whale conservation at Eastern Brazilian Coast. Ocean & Coastal Management. 75, 63-71

Mazzei, E.F.; Bertoncini, A.A.; Pinheiro, H.T.; Machado, L.F. ; Vilar, C.C. ;  Guabiroba, H.C.;  Costa, T.J.F. ; Bueno, L.S. ; Santos, L.N. ;  Francini-Filho, R.B.;  Hostim-Silva, M.;  Joyeux, J.-C. 2016. Newly discovered reefs in the southern Abrolhos Bank, Brazil: Anthropogenic impacts and urgent conservation needs. Marine Pollution Bulletin, 114, 1, 123-133 http://dx.doi.org/10.1016/j.marpolbul.2016.08.059 

Moreno, I.B.; Martins, C.C.A.; Andriolo, A. & Engel, M.H. 2003. Sightings of franciscana dolphins (Pontoporia blainvillei) off Espirito Santo, Brazil. Latin American Journal of Aquatic Mammals. 2(2), 131-132

Morete, M.E.; Bisi, T.L. & Rosso, S. 2007. Temporal pattern of humpback whale (Megaptera novaeangliae) group structure around Abrolhos Archipelago breeding region, Bahia, Brazil. Journal of the Marine Biological Association of the United Kingdom. 87, 87-92 doi: 10.1017/S0025315407054616

Morete, M.E.; Bisi, T.L. & Rosso, S. 2008. Mother and calf humpback whale responses to vessels around the Abrolhos Archipelago, Bahia, Brazil. Journal of Cetacean Research and Management. 9(3), 241-248

Nara, L.; Cremer, M. J.; Farro, A. P. C.; Colosio, A. C.; Barbosa, L. A.; Bertozzi, C.P.; Secchi, E.R.; Pagliani, B.; Costa‑urrutia, P.; Gariboldi, M. C.; Lazoski, C. & Cunha, H. A. 2022. Phylogeography of the Endangered Franciscana Dolphin: Timing and Geological Setting of the Evolution of Populations. Journal of Mammalian Evolution. https://doi.org/10.1007/s10914-022-09607-7 

Negrão, F.; Lacerda, C.H.F.; Melo, T.H.; Bianchini, A.; Calderon, E.N.; Castro, C.B.; Cordeiro, R.T. S.; Dias, R.J.S.; Francini-Filho, R.B.; Guebert, F.M.; Güth, A.Z.; Hetzel, B.; Horta, P. A.;  Lotufo, T.M.C.;  Mahiques, M.M.; Mies, M.; Pires, D.O.;  Salvi, K.P. ; Sumida, P.Y. G. . 2021. The first biological survey of the Royal Charlotte Bank (SW Atlantic) reveals a large and diverse ecosystem complex. Estuarine, Coastal and Shelf Science 255 107363

Rodrigues, V.L.A.; Wedekin, L.L.; Marcondes, M.C.C.; Barbosa, L. & Farro, A.P.C. 2019. Diet and foraging opportunism of the Guiana Dolphin (Sotalia guianensis) in the Abrolhos Bank, Brazil. Marine Mammal Science 2019;1–15. https://doi.org/10.1111/mms.12656

Rossi-Santos, M. R.; Wedekin, L.; Souza-Lima, R. S. 2006. Distribution and habitat use of small cetaceans in the coast of Abrolhos Bank, Eastern Brazil. Latin American Journal of Aquatic Mammals. 5(1),23-28,

Rossi-Santos, M. R.; Wedekin, L.; Monterio Filho, E. L A. 2007. Residence and site fidelity of Sotalia guianensis in the Caravelas River Estuary, eastern Brazil. Journal of the Marine Biological Association of the United Kingdom, 87, 207-212

Rossi-Santos, M. R.; Wedekin, L. W.; Monterio Filho, E. L A. 2010. Habitat Use of the Guiana Dolphin, Sotalia guianensis (Cetacea, Delphinidae), in the Caravelas River Estuary, Eastern Brazil. Latin American Journal of Aquatic Mammals, 8 (1-2), 111-114.

Rupil, G.M.; Bogoni, J.A.; Barbosa, L.; Marcondes, M.C.C. & Farro, A.P.C. 2018. Climate influences on Guiana dolphin diet along the Brazilian coast. Scientia Marina, 82(3), 159-168

Sousa-Lima, R.S. & Clark, C.W. 2008. Modelling the effect of boat traffic on the fluctuation of humpback whale singing activity in the Abrolhos National Marine Park, Brazil. Canadian Acoustics, 36(1), 174-181.

Sucunza, F. et al. 2020b. Population size and IUCN Red Listing of the isolated northern population of the franciscana (Pontoporia blainvillei). Paper submitted to the IWC.

Wedekin, L.L.; Marcondes, M.C.C. et al. 2009. Comunidade de cetáceos da plataforma e talude continental do sul do Banco dos Abrolhos, Brasil. In: Anais VI Encopemaq – Encontro Nacional sobre Pesquisa e Conservação de Mamíferos Aquáticos, Salvador.

Wedekin, L.L.; Neves, M.C.; Marcondes, M.C.C.; Baracho, C.; Rossi-Santos, M.R.; Engel, M.H. & Simões-Lopes, P.C. 2010. Site fidelity and movements of humpback whales (Megaptera novaeangliae) on the Brazilian breeding ground, southwestern Atlantic. Marine Mammal Science. 26(4) 787-802

Wedekin, L.L.; Engel, M.H.; Andriolo, A.; Prado, P.I.; Zerbini, A.N.; Marcondes, M.C.C.; Kinas, P.G. & Simões-Lopes, P.C. 2017. Running fast in the slow lane: rapid population growth of humpback whales after exploitation. Marine Ecology Progress Series. 575, 195-206

Zerbini, A.N.; Andriolo, A.; et. Al. 2006. Satellite-monitored movements of humpback whales Megaptera novaeangliae in the Southwest Atlantic Ocean. Marine Ecology Progress Series. 313: 295–304.


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