Evolutionary history and identification of conservation units in the giant otter, Pteronura brasiliensis

Genetic diversity and population structure in the endangered giant otter, Pteronura brasiliensis

“…Recent work investigating the evolutionary history of the giant otter using mitochondrial control region and cytochrome B sequence data (Pickles et al 2011a) found a strong signal of phylogeographical structure across the range of the giant otter. Four distinct mitochondrial phylogroups were resolved comprising (1) the Amazon River and its tributaries and including the Orinoco basin and the drainages of the Guianas; (2) the Upper Madeira River and the Madre de Dios River; (3) the Iténez subbasin of the Madeira River, and (4) the Pantanal in the southern Paraná-Paraguay drainage (Fig.…”

Advances in the study of giant otter (Pteronura brasiliensis): ecology, behavior, and conservation: a review

“…Pickles et al (2011b) suggest that this may be partially explained by the giant otter longevity (up to 15 years recorded from free-ranging individuals) and a long generation time, reported to be seven years according to Groenendijk et al (2005). Nevertheless, the lower haplotype and nucleotide diversity observed in the Pantanal phylogroup could be due to the more sustained level of giant otter persecution in that region (Pickles et al, 2011b). The authors conclude that the phylogeographic pattern observed in giant otters might be the result of multiple drivers, as the molecular data suggests that no single paleoclimatic or paleoenvironmental event was likely to be responsible for the pattern.…”

“…Regarding the low haplotypic diversity observed in the Pantanal phylogroup, Pickles et al (2011b) recommend special attention as this result may suggest that this phylogroup is the most fragile of them all. Pickles et al (2012) also investigated patterns of population structure in those phylogeographic groups previously described and the data suggest a degree of reproductive isolation between the Iténez (Bolivia) population and the populations of northern South America.…”

“…Their results also corroborate the data obtained by Garcia et al (2007) concerning the lack of strong support to the division of giant otter subspecies. However, Pickles et al (2011b) findings revealed four phylogroups: 1) Iténez and Uruá rivers (located in Bolivia and northwestern Brazilian Amazon, respectively), 2) Madre de Dios (Peru) and Madeira (Brazil) rivers, 3) Pantanal, and 4) Amazon, Orinoco and Guianas. Overall haplotype diversity was very high (h=0.93) in all phylogroups with 41 haplotypes resolved, except in Pantanal (h=0.44) where a single haplotype dominated 75% of all the sequences.…”

“…The authors, however, recommend that a greater number of individuals should be analyzed from both biomes and that nuclear markers should also be applied to certify these results. Based on this suggestion, Pickles et al (2011b) investigated mitochondrial genetic diversity and the evolutionary history of the species analyzing 70 genetic samples distributed among eight countries and four drainage basins. Their results also corroborate the data obtained by Garcia et al (2007) concerning the lack of strong support to the division of giant otter subspecies.…”