(Pontoporia blainvillei)
The franciscana is a shy dolphin. Small groups feed cooperatively, using echolocation to herd bottom-dwelling fish in the cloudy waters they inhabit. The species is generally grouped together with the other, superficially similar ‘river dolphins’, despite the fact that these species are not closely related – their shared characteristics have arisen as a result of having evolved in similar riverine habitats. The franciscana is regularly caught in the gillnets of fishermen who are primarily hunting sharks. The morality rate is suggested to be excessive and unsustainable.
Urgent Conservation Actions
Status surveys to ascertain population size and distribution.
Occurs in coastal waters and estuaries off south-eastern South America.
Evolutionary Distinctiveness
Order: Cetacea
Family: Iniidae
The franciscana is one of the ‘river dolphins’; a group of long-beaked, many toothed cetaceans categorized together for convenience that do not necessarily share a common ancestry but which have some convergent features due to their similar habitats. The river dolphins are some of the lesser known yet more endangered cetaceans.

River dolphins are ancient species which avoided being out competed by more recent dolphin species (Delphinoidea) by emigrating to inland waters at a time of high sea levels. The franciscana is unique in that in later left inland waters returned to the sea, it is the only species of river dolphin to inhabit salt water environments.

The Franciscana is the only species in its genus. The family Platanistidae contains three other species of river dolphin. Platanistidae dates back the Miocene when it evolved from the inhabitants of the Miocene epicontinental seas (seas that stretched across the surface of the continents) up to 23 million years ago. Seas started to flood onto low-lying continents during a time of high sea levels, which inundated the Amazon, Paraná, Yangtze and Indo-Gangetic river basins. The species that remained in the seas were superseded by the radiation (evolution and spread) of the Delphinoidea (non-riverine dolphins). The lowering of global sea levels during the late Miocene and early Pliocene drained the inland sea isolating the archaic river dolphins inside the continents. Unlike the other river dolphins, however, the franciscana followed the marine waters receding from the Paraná basin to colonise the near-shore coastal zone north and south of the La Plata estuary.
Head and body length: 125-175 cm
Weight: 20-61 kg
The franciscana is one of the world’s smallest dolphins. Females are generally larger than males. The skin is greyish brown in colour and paler on the underside. The blowhole is uniquely crescent-shaped and the dorsal fin is small and triangular with a rounded tip. The beak is long and slender containing two rows of teeth and the forehead is slightly bulging.
The franciscana is the only river dolphin species to live in saltwater. It is presumed to locate its food by echolocation and by probing at the sea bed with its beak. It forms groups of usually 2 to 15 individuals, but up to 40 have been seen together. They feed cooperatively by herding bottom-dwelling fish, diving to a maximum depth of 25 metres. The franciscana’s diet consists mainly of bottom feeders including fish, squid and shrimps. The relationships of associated individuals have not been studied so the composition and structure of franciscana society remains unknown. It does not appear to undergo large seasonal migrations and little is known about its daily movements. The franciscana has a 2 year reproductive cycle and the gestation period lasts 10 or 11 months. A single young is born measuring 70-80cm and weighing approximately 8kg and the young is browner in colour than the adult. Lactation may last over 9 months but the young may start to take solid food at around 3 months. Sexual maturity is reached at about 3 years. Specimens have so far been found up to age 16 years at the time of death.
Coastal waters and estuaries. Based on the distribution of sightings and catches the franciscana it seems to inhabit a narrow strip of coastal waters between the surf line and the 30m isobath (indicating areas that are 30 metres below sea level). It is ecologically tied to areas that receive large volumes of nutrient-rich continental runoff and that are influenced by subtropical shelf waters.
The franciscana inhabits shallow coastal and estuarine waters of tropical and temperate regions of the western South Atlantic Ocean. Its distribution extends from Itaúnas (18°25’S), Espírito Santo State in southeastern Brazil, to Golfo Nuevo (42°35’S), Chubut Province, Argentina and includes the La Plata estuary and adjacent rivers. However, the species is not distributed continuously throughout its range. Surveys indicate that franciscanas are extremely rare or absent in two areas of the northern parts of their range. This may be to a number of factors including water depth. Two Franciscana populations are recognized based on differences in morphology and genetic and parasite markers. There is a smaller form in the northern part of the species’ range in the coastal water near Rio de Janeiro (north of 27°S) and a larger form of southern Brazil, Uruguay, and Argentina (south of 32°S). Studies revealed fixed genetic differences between the subpopulations that suggest essentially no effective genetic exchange. Based on available information about the genetics, distribution, morphometrics (or body measurements), and life history parameters of the franciscana populations, it has been proposed that the southern and northern Franciscana subpopulations each be subdivided into two smaller management stocks. The range limits for each of the four stocks were defined as provisional Franciscana Management Areas (FMAs).
Population Estimate
There is no current abundance estimate for the species as a whole, but there is an estimate for one of the management stocks, which inhabits coastal waters of the Brazilian state of Rio Grande do Sul State in the region of southern Brazil and northern Uruguay. Thirty-four franciscanas (in 29 groups) were recorded during aerial surveys of these coastal waters in 1996. Extrapolations of these results indicate that there may be a total abundance of about 42,000 franciscanas. This extrapolated result must be used cautiously, however, because it is based on a density estimate for only a small fraction of the coastline, representing approximately less than one per cent of the franciscanas possible range. Also, the survey was conducted in an area considered to have a relatively high density of franciscanas, and therefore extrapolation to the entire range of the population would exaggerate the estimate. According to the IUCN, financial and logistical constraints may render it unrealistic to expect a more precise or accurate abundance estimate for this population in the foreseeable future.
Population Trend
The overall population trend is unknown, however the subpopulation of Rio Grande do Sul/Uruguay is in decline.
The franciscana is listed as being Data Deficient in the 2004 IUCN Red List of Threatened Species. The Rio Grande do Sul/Uruguay subpopulation is listed as Vulnerable due to a reduction in population size that is suspected to be greater than 30%. Simulations of the Rio Grande do Sul/Uruguay subpopulation using a plausible removal rate based on bycatch data from the local fisheries suggest a decline over three generations of close to 50%. This meets the decline threshold for the franciscana to be classed as Endangered in the IUCN Red List. Additional information from bycatch data and stranding rates suggests a decrease of approximately 70% over the next 20 years. However, the Cetacean Specialist Group was reluctant to recommend Endangered status at this time. Instead, it was agreed to recommend Vulnerable status, with the intention that a reassessment and re-evaluation would be conducted in the near future taking into account newly obtained data on abundance and bycatch and using more advanced statistical methods.
The franciscana is of particular conservation concern because of its restricted distribution and its vulnerability to by-capture in fishing gear. The franciscana is regularly caught in the gillnets of fishermen who are primarily hunting sharks. It may then be used for its meat and oil. In Uruguay between the late 1960s and early 1970s, 1500-2000 individuals were killed annually. The death rate declined with a fall in shark fishing in Uruguay. However, the practice is still common off the coast of Argentina and Brazil and maybe affecting overall population size. The morality rate is suggested to be excessive and unsustainable. The franciscana is also at risk from habitat degradation as coastal industries develop causing increased coastal traffic and pollution. The animals are vulnerable because they live in close proximity to the sources of pollution including sewage outlets, factory discharge and agricultural runoff. There are concerns about the effect these pollutants may have on the health and reproduction of this species.
Conservation Underway

In Brazil, the capture and disturbance of cetaceans is illegal under Federal Law. The franciscana is recognized as nationally vulnerable in the Official List of Brazilian Fauna Species Threatened with Extinction (IBAMA 1989), as well as regionally vulnerable in both Rio de Janeiro State and Rio Grande do Sul State. In Argentina, hunting and capture of cetaceans and pinnipeds (walruses, sea lions and seals) is prohibited under the National Wildlife Conservation Legislation. Regional legislation in the provinces of Buenos Aires, Rio Negro and Chubut also provides indirect protection to the franciscana. In Uruguay, decree adopts measures for the protection and conservation of marine mammals. The National Fisheries Institute is responsible by law for the conservation of marine mammals. Although this legislation appears to offer protection for the franciscana, cooperation with these laws may be minimal due to the negative effects they may have on fisherman’s livelihoods. Furthermore, regulations on fishing practices can not be efficiently imposed until more is known about the location and timing of franciscana bycatch occurrences. A potential alternative may lie in modifying fishing practices and equipment, such as replacing gillnets with longlines as a means to reduce bycatch. The franciscana is listed on Appendix 2 of the Convention on International Trade in Endangered Species (CITES). International trade in this species is monitored through a licensing system to ensure that trade can be sustained without detriment to wild populations.


Direct conservation measures for this species have also been implemented. Proposed by specialists between 2003 and 2005, The ‘National Action Plan for the franciscana’ was finalised in 2010 with the help of numerous Brazilian bodies including the MMA (Ministry of the Environment) and the Chico Mendes Institute. Implemented in the same year, this 5 year plan will guide conservation of the franciscana until 2015. The overall goal of the action plan is to prevent a further fall in franciscana population numbers. This will be achieved by meeting a range of conservation targets including: evaluating the habitats and viability of all populations, implementing fishing control measures, increasing biological and ecological knowledge of the species, and strengthening political and international cooperation for species management. This plan will be coordinated by the National Centre for Research and Conservation of Aquatic Mammals CMA. 

Conservation Proposed
The IUCN has suggested that franciscana conservation maybe advanced through the development of a memorandum of understanding between Argentina, Brazil and Uruguay. This could enable a partnership in researching bycatch rate, population status, habitat degradation and the ecology of the franciscana. Scientists in the three countries are aware of the need to increase research and conservation action, but require external support to achieve this. The IUCN has also proposed the need for a wider management strategy that includes other marine species, especially the depleted fish stocks across the franciscana’s habitat. However, the cultural and economic needs of the fishing communities must also be taken into account to produce a sustainable compromise that benefits local economy and biodiversity both in the long and short term.
Cetacean Specialist Group (1996). Pontoporia blainvillei. In: IUCN 2004. 2004 IUCN Red List of Threatened Species.

Secchi, E.R. & Wang, J.Y. (2003). Pontoporia blainvillei (Rio Grande do Sul/Uruguay subpopulation). In: IUCN 2004. 2006 IUCN Red List of Threatened Species

Nowak, R.M. (ed.) (1999) Walkers Mammals of the World. Sixth edition. The Johns Hopkins University Press, Baltimore and London.

Macdonald, D (ed.) (2001) The New Encyclopedia of Mammals. Oxford University Press, Oxford, New York.

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