Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and ...function.1–4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6–8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars’ spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.
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•Jaguar space use and movements relate consistently to landscape factors•Forest cover, net primary productivity, and road density are key factors•Jaguars perceive their environment equally, irrespective of location or ecoregion•Our results have applications to jaguar conservation throughout the species’ range
Thompson et al. analyze 115 telemetry datasets from jaguars to show spatial needs and movements are predictably related to environmental and human factors across the species’ range. The range-wide consistency in jaguar space use and movements to landscape factors has applications to the conservation of the species throughout its distribution.
•We used the point selection functions and environmental variables measures at multiple scales, in an ecological neighborhood approach.•Jaguars' habitat selection is influenced by tree cover, ...shrubland, and areas with water, with no significant differences between sexes and circadian periods.•Male jaguars actively select crop areas, especially at night, while females avoid them.•Both male and female jaguars used roads.•Based on the analysis of environmental factors conducted in this study, many habitats where jaguars are distributed do not present high suitability.
Improving coexistence between humans and large predators is one of the foremost issues for the survival of large carnivores, especially in the Neotropics, where conflicts for retaliation are still frequent. This problem was increased due to the expansion of agricultural areas, settlements, roads, and the loss of natural habitats. Therefore, a key component in the long-term conservation of carnivores is to reduce animal-human conflicts. We aimed to assess multi-scale habitat selection models, exploring specificities in the selection for each sex and variation for the circadian period. We found that jaguars live in real landscapes of fear with high human and livestock density, where the perception of risk related to humans governed the selection of their resources. However, depending on the sex of individuals and the circadian period, jaguars positively selected some anthropic structures, such as areas of crops and human settlements. This selection suggested an aptitude to use various human-dominated structures and indicated jaguars could locally perceive risks in different ways, depending of sex and day period. Unexpectedly, jaguars presented attraction to roads, sexual or circadian related, regardless of the natural environments. Our results demonstrate that male and female jaguars could use some anthropic features differently in the distinct circadian periods. In addition, we conclude that the knowledge of the habitat selection for jaguars is a crucial component to the structure of the landscape of coexistence of this species and can give us efficient guidance to better comprehend the behavior through different scales of selection and through different periods of the day. Finally, our results show fundamental observations on the movement plasticity of this species for the construction of conservation plans focusing on the coexistence in different landscapes of the Neotropics dominated by humans.
Orientador: Alejandro Edward Jahn
Coorientador: Milton Cezar Ribeiro
Banca: Cesar Cestari
Banca: Karl Stephan Mokross
Resumo: As aves migratórias devem realizar uma série de atividades-chave, ...incluindo migração, criação e muda, para sobreviverem e se reproduzirem com sucesso. É essencial que estes eventos ocorram no período adequado, pois possuem um elevado custo energético, podendo afetar a aptidão da ave. A migração pre-reprodutiva é importante para que a reprodução seja bem sucedida, já que chegar cedo na área reprodutiva tem muitos benefícios (p.e., seleção sexual e aquisição do melhor território). Além disso, a reprodução pode acarretar em um custo de energia que varia entre as populações, dependendo da quantidade de investimento reprodutivo. Igualmente, cada local de reprodução pode diferir na quantidade de alimento disponível e na competição por territórios. Portanto, relação entre a data de chegada e o resultado reprodutivo em tesourinhas foi estada em uma área de Cerrado. Adicionalmente, foi descrita a condição corpórea das tesourinhas fêmeas após da postura de ovos. Trabalhamos na Estação Ecológica de Itirapina, no Brasil, anilhando adultos, procurando adultos anilhados e monitorando os ninhos. Os indivíduos que chegaram cedo nas áreas reprodutivas tiveram um sucesso reprodutivo significativamente mais alto que os indivíduos que chegaram mais tarde, o que é similar a resultados de pesquisas no Hemisfério Norte. Os machos chegaram em média 9.8 dias antes que as fêmeas, possivelmente devido à seleção sexual. Além disso, foi encontrada uma interação significativa entre sucesso reprodutivo e a... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Migratory birds must undertake a number of key activities, including migration, breeding and molt, to successfully reproduce and survive. Properly timing these events is key, because each is energetically costly and can result in significant fitness consequences. Spring migration, in particular is important for successful reproduction, because arriving early to the breeding area has many benefits (e.g., sexual selection and acquisition of a better territory). Furthermore, reproduction represents an energetic cost that varies among populations, depending on the amount of reproductive investment. In addition, each breeding site may differ in the amount of food available and in competition for territories. Therefore, I evaluated the relationship between arrival date and the reproductive outcome in Fork-tailed Flycatchers in the Cerrado ecoregion. I also described body condition of female flycatchers after they laid eggs. Colleagues and I worked at the Estação Ecológica de Itirapina, Brazil. We banded flycatchers, searched for banded adults and monitored their nests. I found that individuals that arrived early to the site achieved significantly higher reproductive success than those that arrived later, similar to findings of numerous studies at north-temperate latitudes. Additionally, males arrived on average 9.8 days before females, which may be related to strong sexual selection. I also found a significant interaction between nest success and energetic among the two populations... (Complete abstract click electronic access below)
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