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Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios

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Artigo
A large scale analysis of threats to the nesting sites of Podocnemis species and the effectiveness of the coverage of these areas by the Brazilian Action Plan for Amazon Turtle Conservation.
(Journal for Nature Conservation,, 2021-06) Fagundes, Camila Kurzmann; Fath, Franciele; Cortes, Lara Gomes; Uhlig, Vívian; Andrade, Paulo C´esar Machado; Vogt, Richard Carl; Pezzuti, Juarez Carlos Brito; Marco Júnior, Paulo De
We evaluated the vulnerability of nesting sites (sandbanks) available to Podocnemis expansa, P. unifilis and P. sextuberculata to human threats and the coverage of these areas by a public policy created to conserve turtles. Species distribution models were used to identify potential nesting areas in the Brazilian Amazon, where sandbanks were mapped through satellite imagery. Values of threats (deforestation, mining, dams and density of human communities) were normalized from 0 to 1 and summed in each 100 km2 pixel. We calculated the mean value of threats and sandbanks area for each basin. Basins with the greatest values for those variables were considered as the most vulnerable. We calculated the coverage of turtle nesting sites that have conservation actions in relation to the sandbanks available and if they are located in the most vulnerable basins. The areas of greatest gaps in conservation actions and vulnerability are located in the Tocantins-Araguaia basins and in rivers such as: Branco, Guapor´e, Amazonas, Solimoes, ˜ Madeira, Tapajos ´ and Xingu. Nesting sites included by the public policy covered 15.17 % of the number of basins and about 21 % of total sandbank areas, encompassing 11 % of the most vulnerable basins and 43 % of their sandbanks. We suggest the prioritization of conservation actions in areas of greatest gaps in conservation activities and vulnerability. In addition, we propose the articulation among institutions and the increase of initiatives of community-based conservation management to increase the geographical coverage of the greatest impacted regions.
Artigo
Eimeria spp. (Apicomplexa: Eimeriidae) in black caiman Melanosuchus niger (Crocodilia: Alligatoridae) from the Amazon Region, Brazil, with a description of two new coccidian species.
(2014-01-29) Viana, Lúcio André; Motta, Adarene Guimarães da Silva; Coutinho, Marcos Eduardo; Rocha, Carlos Frederico Duarte
During November 2011, faeces from 23 black caimans (Melanosuchus niger) were collected from the Brazilian Amazon, and coccidians were found in 83% of the individuals examined. Three Eimeria species were found in the black caiman faeces, two of which were recognised as new species and are subsequently described in the present study. Eimeria paraguayensis was found in 17 of 23 animals sampled. Eimeria nigeri n. sp were found in 16/23 animals examined. Oocysts were spherical to sub-spherical, 29.2 × 28.1 (23–32 × 23–30) μm, and 12.1 × 11.0 μm spherical oocyst residuum was present. Sporocyst was ovoid, 15.5 × 9.7 (8–11 × 12–17) μm, and had a Stieda body at a slightly pointed end. The sporocyst residuum consisted of a compact mass of refractile granules. Eimeria portovelhensis n. sp. were found in 16/23 animals examined. Oocysts were spheroidal, 19.5 × 19.1 (16–21) μm, and had 9.0 × 7.8 μm spherical oocyst residuum present. The spindle-shaped sporocysts were 11.0 × 4.0 (8–13 × 2–5) μm and had two apparent Stieda bodies, one at each pole and with one filament curved at each pole. Sporocyst residuum was present, with four or five small refractile granules. The two new species are differentiated from the five species of Eimeria recorded within the crocodilian family Alligatoridae.
Artigo
MESOCLEMMYS RANICEPS (Amazon Toad-headed Turtle). PHENOTYPIC CHANGE.
(Herpetological Review, 2025-09) Fabio Cunha; TIAGO LUCENA DA SILVA; Victor Silva Vasconcelos
For nearly two decades, the question of the validity of Mesoclemmys heliostemma in relation to that of Mesoclemmys raniceps has been a source of uncertainty. M. heliostemma was (likely incorrectly) “revalidated”. A notable publication described a range extension of the two taxa in sympatry, with the color morph “M. heliostemma” on the right margin of the Jutaí River and M. raniceps on the left margin of the Jutaí River, both in the Municipality of Jutaí, Amazonas, Brazil. We present a series of images of juvenile animals exhibiting the morph color “M. heliostemma” phenotype. We provide a temporal series of a M. raniceps hatchling that displays vibrant yellow-orange facial stripes in the dorsolateral region of the head, starting at the base of the neck and extending to the tip of the snout, similar to the paratype RMNH 31998 of morph color “M. heliostemma”.
Artigo
Priority areas and integrated actions for the conservation of Amazonian turtle populations historically over-exploited by humans.
(Ethnobiology and Conservation, 2022-08-29) Gamba, Fábio Brega; Falcon, Guth Berger; Simoncini, Melina Soledad; Balestra, Rafael Antônio Machado; Malvasio, Adriana
The definition of priority areas for conservation and integrated management actions are essential for the effective maintenance and recovery of natural populations, especially for species overexploited by humans. Amazonian chelonians are a food resource historically used by people, resulting in the decline of species populations and worsening the risk of local extinctions. In this paper, we establish priority areas and define integrated conservation actions for populations of three Amazonian chelonians most threatened by human consumption in Brazil (Podocnemis expansa, P. unifilis and P. sextuberculata). To do so, we used 15 prioritization criteria (ecological, logistical and socioeconomic) estimated with 30 years monitoring data in 15 areas by the Amazon Chelonian Program (in portugues Projeto Quelonios da Amazonia, PQA). Each criterion presented four levels of priority with scores increasing according to the relevance for conservation of chelonian populations. The sum of the scores obtained in each area of the PQA allowed a ranking and four categories of importance for conservation to be defined. We also analyzed the similarity of scores among areas of the PQA and among the prioritization criteria to evaluate the application of integrated conservation action strategies. The areas of PQA were classified as Extremely Important for Conservation (Rebio Trombetas River, Middle Xingu River, Middle Araguaia River, Upper Guaporé River), Very Highly Important for Conservation (Middle Purus River, Middle Juruá River, Crixás-Açu River Mouth, Sub-middle Tapajós River); Highly Important for Conservation (Sub-Middle Araguaia River, Amazonas River Mouth, Middle Mortes River); and Important for Conservation (Middle Guaporé River, Lower Branco River, Flechal River, Afuá River). The prioritization and similarity analyses can support the development of a national integrated plan of conservation actions to reduce the overexploitation of Amazon chelonian populations, according to the ecological, logistical and socioeconomic needs of each PQA area.
Artigo
Procedure for collecting gastric contents in Giant Amazon Turtles Podocnemis expansa (Schweigger, 1812) (testudines, Podocnemididae).
(Braz. J. Vet. Pathol., 2011) Alves Júnior, José R. F.; Sousa, Eliane de; Lustosa, Ana P. G.; Magajevski, Fernanda S.; Girio, Raul J. S.; Werther, Karin
The genus Podocnemis, of the family Podocnemididae, is represented in South America by six species: P. expansa, P. erytrocephala, P. vogli, P. lewyana, P. unifilis and P. sextuberculata (4, 7). The species P. expansa (Fig. 1), known as the giant Amazon turtle, is largely distributed throughout the Amazon river and in most of its tributaries (3). The giant Amazon turtle is found in the states of Amapá, Pará, Amazonas, Rondônia, Acre, Roraima, Tocantins, Goiás and Mato Grosso, encompassing equatorial forests and savanna (cerrado) ecosystems in the north and west-central regions of Brazil (3). This reptile can measure from 75 to 107cm in length, 50 to 75cm in width and weigh up to 60kg (9), being the largest fresh water testudine in South America (2, 5, 8). They are long-lived animals with late sexual maturation and a low individual replacement rate (1, 6).
Artigo
Vulnerability of Giant South American Turtle (Podocnemis expansa) nesting habitat to climate-changed-induced alterations to fluvial cicles.
(Tropical Conservation Science, 2016) Eisemberg, Carla Camilo; Balestra, Rafael Antônio Machado; Famelli, Shirley; Pereira, Fernanda Freda; Bernardes, Virgínia Campos Diniz; Vogt, Richard Carl
A change in seasonal flooding cycles in the Amazon may negatively impact nesting success of the Giant South American Turtle (Podocnemis expansa). Our aim was to devise a technique that could be replicated in the entire Amazon basin, for monitoring alterations in fluvial cycles and their effects on turtle nest mortality. We mapped the spatial distribution and height of P. expansa nests and tested the effects of different inundation scenarios within the Trombetas River Biological Reserve, Para state, Brazil. We also used historical data on water level and hatchling production to test whether the sharp decline in the Trombetas River P. expansa population over the past thirty years was related to detected changes in the flood pulse. Our models indicate that an increase of 1.5 m in the water level is sufficient to decrease the time of exposure to less than the minimum required for incubation and hatching (55 days above the water) in 50% of the nesting area. This model explains the low hatchling production in dry seasons when the total nesting site exposure was less than 200 days. Since 1971, there was na average decline of 15 days per decade in sandbank exposure during the nesting season (a total of 62 days from 1971 to 2015). However, the decrease in sandbank exposure was not significantly correlated with the sharp decline in hatchling production. Changes to the water cycle in combination with the main sources of decline (overharvest, construction of dams, and dredging of riverbeds) might have an accumulative effect on P. expansa populations.