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Raffo DCD, Norris D, Hartz SM, Michalski F. Anthropogenic influences on the distribution of a threatened apex-predator around sustainable-use reserves following hydropower dam installation. PeerJ 2022; 10:e14287. [PMID: 36285331 PMCID: PMC9588301 DOI: 10.7717/peerj.14287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 10/02/2022] [Indexed: 01/24/2023] Open
Abstract
Although previous studies demonstrate declines in many large bodied species following hydropower dam installation, others suggest that some species, including the giant otter (Pteronura brasiliensis) may return to newly created reservoir habitats. Yet, there is a lack of evidence to support such theories. Here, we analyzed the effects of a hydropower dam on giant otters using a before-after control-impact study design in the eastern Brazilian Amazon. We collected data 3 years before (2011-2012 and 2015) and after (2017-2019) dam construction, totaling 6,459 km of surveys along rivers with 43 direct sightings of giant otters. Contrary to expectations, our results revealed that giant otters did not remain nor did they return to the dam reservoir. Beyond the zone directly impacted by the dam giant otter occurrence and relative abundance declined next to sustainable-use reserves where the river was more intensely used by people. Our study showed that in the absence of active management sustainable-use reserves and low human density were not sufficient to maintain this apex-predator. Our findings suggest a need to proactively create and maintain areas with low levels of anthropogenic disturbance to enable sustainable coexistence between energy demands and biodiversity across Amazonia.
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Affiliation(s)
- Deborah C. Dávila Raffo
- Postgraduate Programme in Ecology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil,Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil
| | - Darren Norris
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil,School of Environmental Sciences, Federal University of Amapá, Macapá, Amapá, Brazil,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil
| | - Sandra Maria Hartz
- Postgraduate Programme in Ecology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Fernanda Michalski
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil,Pro-Carnivores Institute, Atibaia, São Paulo, Brazil
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Martins CB, Norris D, Michalski F. Diversity and activity of bird fauna in ephemeral river-created habitats in Amazonia. STUDIES ON NEOTROPICAL FAUNA AND ENVIRONMENT 2021. [DOI: 10.1080/01650521.2021.2005410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Cassiano Bueno Martins
- Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Brazil
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Brazil
| | - Darren Norris
- Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Brazil
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Brazil
- School of Environmental Sciences, Federal University of Amapá, Macapá, Brazil
| | - Fernanda Michalski
- Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Brazil
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Brazil
- Pro-Carnivores Institute, Atibaia, Brazil
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Norris D, Michalski F, Gibbs JP. Community based actions save Yellow-spotted river turtle ( Podocnemis unifilis) eggs and hatchlings flooded by rapid river level rises. PeerJ 2020; 8:e9921. [PMID: 32995087 PMCID: PMC7501802 DOI: 10.7717/peerj.9921] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/21/2020] [Indexed: 11/27/2022] Open
Abstract
The conservation and recovery of increasingly threatened tropical freshwater turtle populations depends on effective management plans and actions. Here we show that community-based actions saved Yellow-spotted river turtle (Podocnemis unifilis) eggs submerged by unseasonal flooding and ensured the release of hatchlings. We recovered 926 eggs and 65 premature hatchlings from 74 submerged nests at 16 flooded nesting areas along 75 km of waterways. The rescued eggs were transferred to a rearing center and incubated. Hatchlings emerged from eggs that had remained underwater for up to two days. Hatchlings were maintained in 250–500 L nursery tanks until yolk sac scars had closed. Healthy hatchlings were then immediately released around the original nesting areas. We released 599 hatchlings (60.4%) from 991 submerged eggs and hatchlings. Egg survival (61.7% (571/926)) was substantially less than hatchling survival (94.2% (599/636)) but within the expected range of values reported for this species. These findings suggest that Yellow-spotted river turtle eggs and embryos are resistant to short-term submersion, which could help explain the widespread distribution of this species across highly seasonal Amazonian rivers. Management plans should take the possible survival of submerged eggs into consideration as part of species conservation and recovery actions.
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Affiliation(s)
- Darren Norris
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil.,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil.,School of Environmental Sciences, Federal University of Amapá, Macapá, Amapá, Brazil
| | - Fernanda Michalski
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil.,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil.,Pro-Carnivores Institute, Atibaia, São Paulo, Brazil
| | - James P Gibbs
- Department of Environmental and Forest Biology, State University of New York, Syracuse, NY, USA
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