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Presents information on a study which examined the habitat use and reproductive ecology of the Ocellated Turkey in Tikal National Park, Guatemala. Study area and methods; Results; Discussion.

Conservation of carnivores involves finding solutions to minimize habitat loss and human-wildlife conflict. Understanding the nature of land-use economics can allow us to mitigate both threats. In the Pantanal, the two main economic activities are cattle ranching and ecotourism, each of which directly and indirectly affect the persistence of jaguars (Panthera onca). To understand how the geography of these economic activities is related to jaguar populations, we developed a jaguar distribution model (JDM), livestock density model, and ecotourism lodge density model for the Pantanal. Due to the recent wildfires within the Pantanal, we also assess the impact of burnt areas that are suitable for jaguars, cattle ranching, and tourism. Our JDM indicate that 64% of the Pantanal holds suitable habitat for jaguars. However, jaguar habitat suitability was positively correlated with ecotourism, but negatively correlated with areas most suitable for intensive cattle-ranching. This demonstrates a biome-wide scenario compatible with jaguar conservation. Of particular concern, recent wildfires overlap most suitable areas for jaguars. If wildfires become increasingly frequent, this would represent a serious threat to jaguars and many other wildlife populations. We emphasize the global importance of the Pantanal wetland ecoregion as a key stronghold for long-term jaguar conservation. [ABSTRACT FROM AUTHOR]

Spacing patterns of large carnivores can affect demographic parameters of populations that, in turn, influence effective population size. As a result, better understanding of spatial structure can provide insight into effective conservation strategies. We examined home-range size, spacing characteristics, and changes in land tenure of radiocollared Amur tigers (Panthera tigris altaica) on the Sikhote-Alin Biosphere Zapovednik, Russia, from 1992 to 2006. We predicted that both sexes would maintain spatially exclusive home ranges and that subadult female tigers would tend toward philopatry and males would disperse. Home ranges (95% fixed kernel estimates; mean ± SD) of resident females (n = 20 home ranges of 14 females; 390 ± 136 km²) were significantly (P = 0.003) smaller than those of males (n = 6 home ranges of 5 males; 1,385 ± 539 km²). Geometric mean overlap between adjacent females (0.11 ± 0.11 SD) did not differ from that between adjacent males (0.14 ± 0.12). All radiocollared male cubs dispersed (n = 7), but only 2 of 6 female cubs dispersed from their natal home ranges. When human-caused mortality was low, female tigers survived long enough to divide their home range with their daughters, resulting in smaller home ranges and a higher density of breeding females. All females reproduced in these smaller territories, suggesting that they maintained home ranges that were larger than needed to meet reproductive demands. However, when human-caused mortality was high, females often did not survive long enough to bequeath home ranges to daughters, and population density was apparently maintained well below carrying capacity. The impacts of poaching appear to extend beyond the direct loss of individuals, and therefore reserves must be well protected if they are to serve as source populations for adjacent, unprotected areas of tiger habitat. [ABSTRACT FROM AUTHOR]

Presents information on a study that determined macro-habitat use by female black bears in western Maryland. Field-site description; Methodology of the study.

Understanding the effects of human disturbance on endangered wildlife populations is critical to their conservation. We examined the effects of roads and human disturbance on the survivorship and foraging efficiency of Amur tigers ( Panthera tigris altaica ) on and near Sikhote-Alin State Biosphere Zapovednik, Primorye Krai ( province), Russia. To evaluate the effects of roads, we estimated survivorship of radiocollared tigers and their cubs living in three types of areas: (1) areas with primary roads, (2) areas containing secondary roads, and (3) areas with minimal or no road access. We classified a tiger into one of these three treatments based on which types of roads bisected their 50% minimum convex polygon home ranges. Over a 9-year period (1991–2000), adult female survival was greatest (χ 2 = 12.2, df = 2, p = 0.002) for radiocollared tigers in roadless areas. All adult female tigers in roadless areas survived their tenure in those locations (n = 2), whereas all died or disappeared prematurely from areas with primary roads (n = 6). Cub survival was lower in areas with primary and secondary roads than in roadless areas (χ 2 = 10.9, df = 1, p < 0.009). We evaluated the effects of human disturbance at kill sites by examining 86 kills made by 15 tigers determining whether human disturbance had occurred at the kill site, and examining prey carcasses after tigers left, to estimate the percent meat eaten and whether the tiger abandoned the kill following human disturbance. Tigers undisturbed at kills consumed more meat ( Z = 3.71, p = 0.0002) from each kill than disturbed tigers did. Undisturbed tigers also spent more time at each kill site than disturbed tigers did ( Z = 2.3; p = 0.02). Abandonment of kills occurred in 63% of 24 instances when tigers were disturbed by people. Because roads decrease the survivorship and reproductive success of tigers, we recommend that in habitats managed for tigers, construction of new roads should be prohibited wherever possible and access to secondary roads (e.g., logging roads) should be reduced or prevented wherever possible. Protected areas seem to cease functioning as source populations where road access exists, and unprotected areas—the majority of Amur tiger range—cannot sustain stable populations with the increasing threat of human access to tiger habitat. [ABSTRACT FROM AUTHOR]