RESUMEN
Coastal marine atmospheric fog has recently been implicated as a potential source of ocean-derived monomethylmercury (MMHg) to coastal terrestrial ecosystems through the process of sea-to-land advection of foggy air masses followed by wet deposition. This study examined whether pumas (Puma concolor) in coastal central California, USA, and their associated food web, have elevated concentrations of MMHg, which could be indicative of their habitat being in a region that is regularly inundated with marine fog. We found that adult puma fur and fur-normalized whiskers in our marine fog-influenced study region had a mean (±SE) total Hg (THg) (a convenient surrogate for MMHg) concentration of 1544 ± 151 ng g-1 (N = 94), which was three times higher (P < 0.01) than mean THg in comparable samples from inland areas of California (492 ± 119 ng g-1, N = 18). Pumas in California eat primarily black-tailed and/or mule deer (Odocoileus hemionus), and THg in deer fur from the two regions was also significantly different (coastal 28.1 ± 2.9, N = 55, vs. inland 15.5 ± 1.5 ng g-1, N = 40). We suggest that atmospheric deposition of MMHg through fog may be contributing to this pattern, as we also observed significantly higher MMHg concentrations in lace lichen (Ramalina menziesii), a deer food and a bioindicator of atmospheric deposition, at sites with the highest fog frequencies. At these ocean-facing sites, deer samples had significantly higher THg concentrations compared to those from more inland bay-facing sites. Our results suggest that fog-borne MMHg, while likely a small fraction of Hg in all atmospheric deposition, may contribute, disproportionately, to the bioaccumulation of Hg to levels that approach toxicological thresholds in at least one apex predator. As global mercury levels increase, coastal food webs may be at risk to the toxicological effects of increased methylmercury burdens.
Asunto(s)
Aerosoles/química , Contaminantes Atmosféricos/análisis , Bioacumulación , Ciervos/metabolismo , Cadena Alimentaria , Líquenes/química , Compuestos de Metilmercurio/análisis , Puma/metabolismo , Contaminantes Químicos del Agua/análisis , Tiempo (Meteorología) , Contaminantes Atmosféricos/farmacocinética , Animales , Bahías , California , Cabello/química , Herbivoria , Compuestos de Metilmercurio/farmacocinética , Océano Pacífico , Conducta Predatoria , Puma/crecimiento & desarrollo , Agua de Mar/química , Vibrisas/química , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
BACKGROUND: Overexploitation and persecution of large carnivores resulting from conflict with humans comprise major causes of declines worldwide. Although little is known about the interplay between these mortality types, hunting of predators remains a common management strategy aimed at reducing predator-human conflict. Emerging theory and data, however, caution that such policy can alter the age structure of populations, triggering increased conflict in which conflict-prone juveniles are involved. RESULTS: Using a 30-year dataset on human-caused cougar (Puma concolor) kills in British Columbia (BC), Canada, we examined relationships between hunter-caused and conflict-associated mortality. Individuals that were killed via conflict with humans were younger than hunted cougars. Accounting for human density and habitat productivity, human hunting pressure during or before the year of conflict comprised the most important variables. Both were associated with increased male cougar-human conflict. Moreover, in each of five regions assessed, conflict was higher with increased human hunting pressure for at least one cougar sex. CONCLUSION: Although only providing correlative evidence, such patterns over large geographic and temporal scales suggest that alternative approaches to conflict mitigation might yield more effective outcomes for humans as well as cougar populations and the individuals within populations.
Asunto(s)
Conservación de los Recursos Naturales , Puma/crecimiento & desarrollo , Animales , Conservación de los Recursos Naturales/métodos , Ecosistema , Actividades Humanas , Humanos , Regulación de la Población/métodos , Dinámica PoblacionalRESUMEN
Strictly Protected Areas and riparian forests in Brazil are rarely large enough or connected enough to maintain viable populations of carnivores and animal movement over time, but these characteristics are fundamental for species conservation as they prevent the extinction of isolated animal populations. Therefore, the need to maintain connectivity for these species in human-dominated Atlantic landscapes is critical. In this study, we evaluated the landscape connectivity for large carnivores (cougar and jaguar) among the Strictly Protected Areas in the Atlantic Forest, evaluated the efficiency of the Mosaics of Protected Areas linked to land uses in promoting landscape connectivity, identified the critical habitat connections, and predicted the landscape connectivity status under the implementation of legislation for protecting riparian forests. The method was based on expert opinion translated into land use and land cover maps. The results show that the Protected Areas are still connected by a narrow band of landscape that is permeable to both species and that the Mosaics of Protected Areas increase the amount of protected area but fail to increase the connectivity between the forested mountain ranges (Serra do Mar and Serra da Mantiqueira). Riparian forests greatly increase connectivity, more than tripling the cougars' priority areas. We note that the selection of Brazilian protected areas still fails to create connectivity among the legally protected forest remnants. We recommend the immediate protection of the priority areas identified that would increase the structural landscape connectivity for these large carnivores, especially paths in the SE/NW direction between the two mountain ranges.
Asunto(s)
Migración Animal , Conservación de los Recursos Naturales/métodos , Ecosistema , Bosques , Panthera/crecimiento & desarrollo , Puma/crecimiento & desarrollo , Animales , Brasil , HumanosRESUMEN
Objetivou-se com o presente estudo monitorar o comportamento do uso territorial de um macho de onça parda, capturado no Parque Estadual da Serra do Brigadeiro (PESB), por meio da telemetria, usando colar de GPS via Satélite Globalstar. O monitoramento de doze meses resultou na transmissão via satélite de 328 localizações, as quais sugerem que a área utilizada por esse felino seja de aproximadamente 610km2, sendo esta a maior área já descrita para a espécie. Foi possível observar que apenas 20% das localizações ocorreram dentro da área do PESB. O comportamento territorial observado neste trabalho mostra a vulnerabilidade do animal a ações antrópicas, como a caça, atropelamentos e o contato com patógenos entre animais silvestres e domésticos. Observou-se também que duas rodovias configuram barreiras artificiais para o deslocamento do animal, possivelmente impedindo o fluxo gênico entre o PESB e dois outros importantes parques. Com os dados levantados é possível a sugestão de ações de manejo, como a criação de uma conectividade efetiva entre o PESB, o Parque Estadual do Rio Doce e o Parque Nacional do Caparaó, o que poderia contribuir para o intercâmbio genético entre as populações e, dessa forma, favorecer a conservação não somente da onça parda.
We aimed to study the territorial behavior of a male cougar, captured in the Parque Estadual da Serra do Brigadeiro (PESB), using a GPS collar and the Globalstar Satellite. Monitoring the animal for nine months we obtained 328 locations. The data suggest that the area used by this feline is approximately 610km2, the largest area described for this specie. It was also possible to observe that only 20% of the locations of the animal occurred within the PESB area. The territorial behavior observed in this study shows the vulnerability of the animal to human activities such as hunting, road kill and contact with pathogens from domestic animals. It was also observed that two roads constitute artificial barriers for animal movement, possibly preventing gene flow between the PESB and two other parks. The creation of an effective connectivity between the PESB, the Parque Estadual do Rio Doce and the Parque Nacional do Caparaó is critical to ensure genetic exchange between the animal populations and thereby promote their conservation.
Asunto(s)
Animales , Telemetría/estadística & datos numéricos , Telemetría/veterinaria , Puma/crecimiento & desarrollo , TerritorialidadRESUMEN
A predação de rebanhos domésticos por onças-pintadas (Panthera onca) e onças-pardas (Puma concolor) foi quantificada de 1998 a 2000 e a opinião local para resolver o conflito foi investigada em duas comunidades quilombolas na Mata Atlântica. Os responsáveis pelas propriedades foram entrevistados regularmente de maio de 2000 a janeiro de 2001. A predação foi dependente do número de animais domésticos nas propriedades, foi aparentemente seletiva e possivelmente sazonal. O prejuízo econômico foi alto quando associado com o baixo número de criações. A população expressou uma visão bastante negativa frente à presença de onças e a maior parte (54 por cento) sugeriu o extermínio desses animais. Conhecer a percepção local é fundamental para adotar um planejamento participativo que reduza as perdas dos proprietários e garanta a conservação dos grandes felinos.
Domestic livestock predation by jaguars (Panthera onca) and pumas (Puma concolor) was recorded from 1998 to 2000 and local opinion to solve the conflict was investigated in two quilombola communities in the Atlantic Forest. The householders were interviewed regularly from May 2000 to January 2001. Predation depended on the number of domestic animals per household, and was apparently selective and possibly seasonal. The economic damage was high when associated with the low livestock number. People's attitude towards predators was negative and most of those surveyed (54 percent) suggested these animals should be eliminated. Knowing the local perception is essential to adopt a participative management to reduce household losses and to guarantee large cats' conservation.