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| Ecology and Behavior |
Habitat: Coastal
There is very little known about the franciscana's natural history. This is due to two factors the difficulty of observing them in nature, and the paucity of research effort. They are found singly or in small groups of up to 15 individuals. In general, they appear to avoid vessels, and are not aerially active.
Reproduction:
Peak calving for this species is in November and December. There has not been much research on the life history of this species, but sexual maturity may occur as early as 3 years. At birth, franciscana measure about 60-80 cm. |
| Feeding and Prey |
Feeding Mode: Opportunistic
Franciscana feed mostly near the bottom on several species of fish, cephalopods, and crustaceans. Cooperative feeding has been observed in Argentina. |
| Threats and Status |
Main threats include:
Incidental mortality in gillnet fisheries (takes at least 1,500 animals per year)
Habitat degradation
Pollution
Conservation status:
Total abundance of the species is not known, but the gillnet mortality alone is not thought to be sustainable. Data Deficient (IUCN); Not Listed (ESA).
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| References |
BORDINO, P., G. THOMPSON, AND M. INIGUEZ. 1999. Ecology and behaviour of the franciscana (Pontoporia blainvillei) in Bahia Anegada, Argentina. Journal of Cetacean Research and Management 1:213-222.
BROWNELL JR., R. L. 1989. Franciscana Pontoporia blainvillei (Gervais and d'Orbigny, 1844). Pp. 45-68 in S. H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 4 River dolphins and the larger toothed whales. Academic Press.
CRESPO, E. A. 2002. Franciscana Pontoporia blainvillei. Pp. 482-485 in W. F. Perrin, B. Würsig and J. G. M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
CRESPO, E. A., G. HARRIS, AND R. GONZALEZ. 1998. Group size and distributional range of the franciscana, Pontoporia blainvillei. Marine Mammal Science 14:845-848.
PINEDO, M. C. 1991. Development and variation of the franciscana, Pontoporia blainvillei. Ph.D. disertation, University of California, Santa Cruz.
PINEDO, M. C., R. PRADERI, AND R. L. BROWNELL JR.. 1989. Review of the biology and status of the franciscana Pontoporia blainvillei. Pp. 46-51 in W. F. Perrin, R. L. Brownell, Z. Kaiya and L. Jiankang, eds. Biology and conservation of the river dolphins. IUCN.
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| Relevant OBIS-SEAMAP Datasets (# sets:
0) |
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