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1.
Ecol Evol ; 13(4): e9968, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37038526

ABSTRACT

The buffy-tufted-ear marmoset (Callithrix aurita) is a small primate endemic to the Brazilian Atlantic Forest biome, and one of the 25 most endangered primates in the world, due to fragmentation, loss of habitat, and invasion by allochthonous Callithrix species. Using occurrence data for C. aurita from published data papers, we employed model selection using Akaike Information Criterion corrected for small samples and cumulative AICc weight (w +) to evaluate whether fragment size, distance to fragments with allochthonous species, altitude, connectivity, and surrounding matrices influence the occurrence of C. aurita within its distributional range. Distance to fragments with C. jacchus (w + = 0.94) and nonvegetated areas (w + = 0.59) correlated negatively with C. aurita occurrence. Conversely, the percentage of agriculture and pasture mosaic (w + = 0.61) and the percentage of savanna formation (w + = 0.59) in the surrounding matrix correlated positively with C. aurita occurrence. The findings indicate that C. aurita is isolated in forest fragments surrounded by potentially inhospitable matrices, along with proximity of a more generalist and invasive species, thereby increasing the possibility of introgressive hybridization. The findings also highlighted the importance of landscape elements and allochthonous congeneric species for C. aurita conservation, besides indicating urgency for allochthonous species management. Finally, the approach used here can be applied to improve conservation studies of other endangered species, such as C. flaviceps, which is also endemic to the Brazilian Atlantic Forest and faces the same challenges.

2.
Biol Conserv ; 251: 108796, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33041345

ABSTRACT

Poaching activity has been described in the literature as harmful due to impacts on biodiversity, especially in protected areas. Although the main reason for this activity is subsistence, in many regions motivation goes beyond the limits of food necessity. We applied single-species, single season occupancy models to evaluate the spatial distribution of poachers and identify potential poaching hotspots in a mosaic of protected areas in the Caatinga domain, northeastern Brazil. We used camera-traps over a period of 200 days at 60 sites randomly selected. We used distances from human settlements, roads and the nearest water holes, frequency of game species and sampling effort as covariables that could influence poachers' occupancy and detectability and to identify potential poaching areas. Occupancy poachers were higher in sites with higher frequency of game species. Frequency of game species and distance from roads had a negative effect on the detectability of poachers. Spatial analysis indicated three critical poaching areas within and around the Boqueirão da Onça National Park, associated with roads and some isolated cattle and goat farms. In this study, we provided an assessment of poaching spatial patterns in relation to different landscape elements and biotic influences, indicating critical areas where enforcement efforts should be focused. Hotspots are clearly concentrated within and on the edge of National Park. The approach presented here to identify poaching hotspots is effective and economical, and therefore may be applied in other protected and non-protected areas throughout the world.

3.
Ciênc. rural (Online) ; 45(2): 288-291, fev. 2015. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1479636

ABSTRACT

O presente estudo relata ixodídeos em mamíferos silvestres no Parque Nacional da Serra da Canastra e arredores, no estado de Minas Gerais, Brasil. De julho de 2005 a junho de 2014, foram coletadas 58 larvas, 133 ninfas e 43 carrapatos adultos em 40 eventos de captura de mamíferos de vida livre do Parque e arredores. Nos hospedeiros da ordem Carnivora, foram identificados Amblyomma ovale Koch, 1844, Amblyomma sculptum Berlese, 1888, Amblyomma tigrinum Koch, 1844, Dermacentor nitens Neumann, 1897 e Rhipicephalus microplus (Canestrini, 1888). Em hospedeiros da ordem Xenarthra, foram identificados espécimes de Amblyomma pseudoconcolor Aragão, 1908 e A. sculptum. Este estudo relata os primeiros registros dos ixodídeos D. nitens e R. microplus parasitando Lycalopex vetulus, e A. ovale em Leopardus tigrinus no país. Os achados do presente estudo indicam a proximidade entre os animais domésticos e silvestres causada pela expansão agropecuária no território brasileiro.


This research­­­­­ reports ticks on wild mammals from the Serra da Canastra National Park and surrounding areas, in Minas Gerais state, Brazil. From July 2005 to June 2014, 58 larvae, 133 nymphs and 43 adult ticks were collected in 40 capture events of free-living mammals at the Park and surrounding areas. The tick species Amblyomma ovale Koch, 1844, Amblyomma sculptum Berlese, 1888, Amblyomma tigrinum Koch, 1844, Dermacentor nitens Neumann, 1897, and Rhipicephalus microplus (Canestrini, 1888) were identified on hosts of the order Carnivora. Specimens of Amblyomma pseudoconcolor Aragão, 1908 and A. sculptum were identified on the hosts of the order Xenarthra. We provide the first records of D. nitens and R. microplus ticks parasitizing Lycalopex vetulus, and A. ovale on Leopardus tigrinus in Brazil. The findings of this research indicate the sharing of environment by domestic and wild animals caused by agricultural expansion in the Brazilian landscape.


Subject(s)
Animals , Animals, Wild/parasitology , Tick Infestations/veterinary , Ixodidae/growth & development , Mammals/parasitology
4.
Genetica ; 139(3): 369-81, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21298553

ABSTRACT

Maned wolves are large canids currently considered vulnerable to extinction due to habitat loss. They are still commonly found within the urban mesh inside the Brazilian Federal District (Distrito Federal--DF), in nearby Protected Areas (PAs), and in surrounding farms. We evaluated the genetic diversity of maned wolves in three PAs of the DF, using both invasive and noninvasive techniques to obtain DNA that was later amplified for five microsatellite markers. We sampled 23 wolves: 10 with the noninvasive method, three captured in traps, six road-killed, and four rescued in urban areas. In Águas Emendadas Ecological Station (ESECAE) we also used samples from six specimens captured between 1997 and 1998 for a temporal comparison. For maned wolves, non-invasive techniques are affordable and easier to conduct in the field, while laboratory costs are much lower for invasive samples. Hence, a sampling strategy combining both techniques may provide an interesting approach for molecular ecology studies requiring comprehensive coverage of local individuals. On the basis of such integrated sampling scheme, our analyses indicated that none of the investigated populations currently present deviations from Hardy-Weinberg expectations or indication of inbreeding. Furthermore, in ESECAE there was no reduction in genetic diversity during the last 9 years. Overall, maned wolves did not present evidence of genetic structuring among the three sampled PAs. These results thus indicate that individual exchange among PAs is still occurring at sufficient rates to avoid differentiation, and/or that the recent fragmentation in the region has not yet produced measurable effects in the genetic diversity of maned wolves.


Subject(s)
Canidae/genetics , Conservation of Natural Resources , Ecosystem , Genetics, Population , Alleles , Animals , Brazil , DNA, Mitochondrial/genetics , Female , Gene Frequency , Genetic Variation , Male , Microsatellite Repeats/genetics , Molecular Typing
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