RAN
URI permanente desta comunidadehttps://bdc.icmbio.gov.br/handle/cecav/1401
Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios
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4 resultados
Resultados da Pesquisa
Item Evolutionary significant units within populations of neotropical broad-snouted caimans (Caiman latirostris, Daudin, 1802).(Journal of Herpetology, 2018-07-20) Borges, Vitor S.; Santiago, Pamela C.; Lima, Nathália G. S.; Coutinho, Marcos E.; Eterovick, Paula C.; Carvalho, Daniel C.Evolutionary significant units are an important level of biodiversity in management and conservation programs. Molecular data are considered a high priority for efficient Broad-Snouted Caiman (Caiman latirostris) conservation. In this study, we used two mitochondrial (COI and 16sRNA) and one nuclear (RAG1) molecular markers to test the hypothesis of independent evolution of geographic lineages across Brazilian river basins. We captured caimans at night and cut one or more scales from the tail for genetic analyses. We obtained genetic data from 37 C. latirostris captured between September 2012 and June 2013 from 13 locations throughout four river basins: Doce, Jequitinhonha, Paraná, and São Francisco. Clades were closely associated to river basins, supporting the presence of three distinct phylogenetic lineages within the 1) São Francisco and Jequitinhonha, 2) Doce, and 3) Paraná river basins. These lineages have been isolated probably since the rise of Pleistocene low sea levels and do not have recent gene flow. They have mtDNA reciprocal monophyly and, therefore, present compelling evidence to be considered as evolutionary significant units. Considering the hidden genetic diversity within this species, we recommend conservation efforts for all three independent units within C. latirostris.Item Distribuição das populações de jacaré-do-papo-amarelo (Caiman latirostris, Daudin 1802, Alligatoridae) na bacia do Rio São Francisco, Brasil.(Braz. J. Biol., 2010) ilogonio, R.; Assis, V.B.; Passos, L.F.; Coutinho, M.E.Fizemos o levantamento de populações do jacaré-de-papo-amarelo, Caiman latirostris, ao longo da bacia do rio São Francisco, a partir do reservatório de Três Marias, no Estado de Minas Gerais, até a foz do rio, na divisa entre os Estados de Sergipe e Alagoas. Registramos a ocorrência de jacarés em 61% das localidades visitadas (n = 64), nas quais a presença de C. latirostris foi confirmada em 44% dos casos. Os jacarés ocorreram em ambientes lênticos e lóticos, muito embora tenhamos observado uma preferência por pequenas represas, lagoas marginais e áreas alagáveis. Apesar da pressão de caça e da modificação dos hábitats naturais, nossos resultados são evidências de que as populações de C. latirostris ao longo da bacia do São Francisco não estão fragmentadas.Item Demographic and growth analysis of broad snouted caiman (Caiman latirostris) in a disturbed environment in southeastern Brazil.(Herpetological Journal, 2014-10) Passos, Luiza Figueiredo; Coutinho, Marcos Eduardo; Young, Robert JohnCrocodilian life history traits exhibit strong size and age dependence, which is determined, ultimately, by how fast individuals grow. Crocodilian population dynamics are dependent on environmental conditions such as local temperatures and hydrology. From February 2010 to October 2011 we conducted monthly spotlight surveys to study a broad-snouted caiman population at the Três Marias Hydro-electric Reservoir, southeast Brazil. A total of 12 spotlight surveys were conducted (17.3 to 48.0 km in length), and animals were captured, measured and marked whenever possible. Data were obtained on population size, sex structure, survival, distribution and growth. The number of caimans counted, including hatchlings, varied from 6 to 78 per survey. Marked individuals showed a growth rate that varied between 0.0 and 0.3 cm*day-1 SVL, and between -6.0 and 8.0 g*day-1 body mass. Polyphasic growth was associated with rainfall and water level, which in turn were associated with changes in temperature and diet. The species seems to be resistant to the ecological impacts of damming, an important conservation conclusion considering the large number of hydroelectric dams within the species’ range in Brazil.Item Body Condition and Blood Biochemistry of Free-Range Caiman latirostris in Northeast Brazilian Atlantic Forest(Journal of experimental Zoology. A Ecol Integr Physiol., 2025) Gabriela Mota Gama; Luiza Figueiredo Passos; Adriano Pereira Paglia; Marcos Eduardo CoutinhoThe Atlantic Forest broad-snouted caiman (Caiman latirostris) inhabits regions within one of the world's most ecologically diverse ecosystems, yet few studies have explored the relationship between body condition, blood biochemistry, and environmental factors in the wild. Our study investigated the effects of sex, ontogeny, habitat, and environmental variables on the body condition and blood biochemistry of free-ranging caimans from the state of Alagoas, Northeast Brazil. From 2020 to 2022, we captured 75 caimans across three sites in different seasons. Results revealed sex-specific responses to seasonal and Interannual weather changes, with females showing higher body condition in the wet season, while males peaked in the dry season. Elevated glucose, total protein, albumin, triglycerides, and fructosamine were linked to higher body condition and larger individuals, while elevated aspartate aminotransferase to low body condition. Seasonal rainfall influenced blood parameters, with the dry season associated with higher creatinine, calcium, and alanine aminotransferase levels, and the wet season with higher total protein, sodium, and potassium. Differences in glucose, alkaline phosphatase, and gamma-glutamyl transferase across sites pointed to physiological effects of human activities. Blood biochemical values varied widely, with some exceeding reported species ranges. These findings highlight the need to interpret physiological data within the context of local habitat and environmental conditions. Conservation strategies should go beyond species presence and habitat preservation, incorporating pollution control. Our study advances understanding of Caiman latirostris ecophysiology, offering valuable insights for the conservation and management of crocodilian populations in both wild and captive environments.