Navegando por Assunto "Amazon"

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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
AMAZONIAN MANATEES (Trichechus inunguis) INHABITING AN EQUATORIAL METROPOLIS: HISTORICAL RECORDS AND MATING ACTIVITY NEAR BELÉM, NORTHERN BRAZIL
(2021-12-22) Emin-Lima, Renata; Costa, Alexandra Fernandes; Attademo, Fernanda Löffler Niemeyer; Hauser-Davis, Rachel Ann; Luna, Fábia de Oliveira; Siciliano, Salvatore
The West Indian manatee Trichechus manatus Linnaeus, 1758 and the Amazonian manatee T. inunguis (Natterer, 1883) occur in the Marajó Bay area and in the inlets and channels near Belém. The Amazon Aquatic Mammal Study Group (GEMAM) coordinates a collaborative network for trapped and rescued manatees along the coast of the state of Pará and in the interior of Belém. The presence of the Amazonian manatee is confirmed with the rescue and sightings in the great Belém area. The samples of these manatees are housed in collections of institutions such as MPEG and ICMBio, CMA. On October 31st 2021, Amazonian manatees were sighted swimming near a beach in the Mosqueiro district, in greater Belém. Residents and tourists took images that show a mating behavior reported in the literature for Trichechus spp. The waters in this area are turbid and these records are a significant opportunity to understand this behavior. The event may suggest that Amazonian manatees are returning to the Belém area and its surroundings, as well as to the east coast of the state of Pará, possibly due to the synergic effects of SARS-CoV-2, providing areas less disturbed by humans, pandemic and the current climate change scenario, which would be a hope for this endangered species.
Artigo
Bat flies (Diptera: Streblidae) of Phyllostominae and Stenodermatinae (Chiroptera: Phyllostomidae) bats from cocoa and natural areas of Amazonia
(2023-11-12) França, Júlia de Oliveira; Alexandre, Rafaela Jemely Rodrigues; Correia, Letícia Lima; Souza, Loyriane Moura; Graciolli, Gustavo; Aguiar, Ludmilla Moura de Souza; Vieira, Thiago Bernardi
Streblidae and Nycteribiidae are ectoparasitic flies exclusive to bats, with an estimated diversity of over 100 species in Brazil. Its distribution and abundance may be influenced by host’s shelter, geographic distribution, behavior, and size. Bat species respond differently to environmental changes, such as changing land use and land cover for cocoa production in the eastern Amazon. We sought to investigate the community of ectoparasite flies (Diptera: Streblidae) on Phyllostominae and Stenodermatinae (Chiroptera: Phyllostomidae) bats and the parasite-host interactions in cacao plantations and natural areas in the Brazilian Amazon. Twenty-two bats were collected, reaching a total of 54 flies. The observed richness was 15 (estimated in 24) species, with Trichobius dugesioides being the most abundant. The cacao plantations showed greater richness, eight species more than the natural ones, however, showing the absence of a specific distribution pattern for each area. This result may be because human interference in cocoa areas are barely perceptible, at least for the bats studied. In addition, the adoption of cabruca-type cocoa plantations can influence the result, as previously shown in the literature.
Artigo
Bats (Mammalia, Chiroptera) and bat flies (Diptera, Streblidae) found in the largest sandstone cave of Brazil
(2023-05-12) Vieira, Thiago Bernardi; Correia, Letícia Lima; Pena, Simone Almeida; Gomes-Almeida, Brenda ; Urbieta, Gustavo Lima; Graciolli, Gustavo; Palheta, Leandra Rose; Caçador, Antônio Wesley Barros; Aguiar, Ludmilla
Bats provide essential ecosystem services and some are cave dependent. Caves favour the association of bats with ectoparasite Diptera, however, they are poorly sampled in the Amazon biome. Here we present the first description of a community of bats and bat flies from the largest sandstone cave in Brazil, the Planaltina cave, located in the municipality of Brasil Novo, state of Pará. Diptera were removed from captured bats and taken to the laboratory for identification. From nine species of bats belonging to four families we recorded 17 species of Diptera, 13 were monoxenous. A possible explanation for the monoxenous parasites collected is that flies have poor survival in unusual hosts. These results are an indicator that the Streblid species are host-specific since even if the hosts take refuge in the same cave, they will not share their parasites. Therefore, the present study provides important information on the parasite-host dynamics in a cave, thus highlighting the importance of cave as are essential shelters for bat species and, despite reported cases of cohabitation, mixed colonies are unlikely to form.
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
Three new troglobitic Coarazuphium (Coleoptera, Carabidae, Zuphiini) species from a Brazilian hotspot of cave beetles: exploring how the environmental attributes of caves drive ground-beetle niches
(2022-06-10) Pellegrini, Thais Giovannini; Ferreira, Rodrigo Lopes; Zampaulo, Robson de Almeida; Vieira, Letícia
Three new species of troglobitic beetles of the genus Coarazuphium are described from specimens collected in iron ore caves in the Flona de Carajás in Brazil, doubling the number of known species for the Carajás region. The new species of Coarazuphium are morphologically similar to the already described species from the same region and are distributed in a small geographic range. From all Coarazuphium species of the region, including the new ones, two stand out, C. spinifemur and C. xingu sp. nov., which are the smallest Coarazuphium species. Both species have shorter legs and antennae when compared to the others. The main characteristic that differentiates C. xikrin sp. nov. and C. kayapo sp. nov. from the other two species from the Carajás region, C. tapiaguassu and C. amazonicum, is that the new species have more numerous setigerous punctures dorsally on the head. With the three new species added to the six already described congeners, the area of intense mining of the Carajás region includes the highest diversity of obligatory cave-dwelling beetles in Brazil, representing a hotspot of cave beetles. Coarazuphium xikrin sp. nov. and C. amazonicum co-occur in some of the caves of the Carajás region, which is possible due to putative niche differentiation between the species. These findings highlight the importance of maintaining legal provisions that ensure the preservation of caves, especially those most relevant regarding physical and biotic aspects, which is crucial for the conservation of Brazilian subterranean biodiversity.
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.