Mariana Nagy-Reis

• PhD in Ecology
• Wildlife Habitat Specialist at Ministry of Water Land and Resouce Stwardship

Small felids influence ecosystem dynamics through prey and plant population changes. Although most of these species are threatened, they are accorded one of the lowest research efforts of all felids, and we lack basic information about them. Many felids occur in sympatry, where intraguild competition is frequent. Therefore, assessing the role of in...

Understanding the underlying mechanisms driving population demographics such as species-habitat relation- ships and the spatial scale in which these relationships occur is essential for developing optimal management strategies. Here we evaluated how landscape characteristics and winter severity measured at three spatial scales (1 km2, 9 km2, and hu...

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropica...

A recurring challenge for resource managers and decision makers is quantifying the trade-offs associated with alternative recovery actions for threatened species. Structured decision-making approaches can help evaluate such complex problems by formalizing objectives and constraints into functions that quantify the benefits and costs associated with...

Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss,...

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestrial-ity is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs...

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs,...

Habitat use is a dynamic process that varies spatially and temporally. Such variations can be associated with environmental heterogeneity and seasonal fluctuations in food availability. We investigated the habitat use of three sympatric Amazonian primates (Humboldt’s cuxiu—Chiropotes sagulatus, pied tamarin—Saguinus bicolor, and tufted capuchin mon...

Models of population dynamics are a central piece for harvest management, allowing managers to evaluate alternative strategies and to identify uncertainty. Here we present a density-dependent population dynamics model that can be used in conjunction with adaptive management to optimize big game management, designed to use data commonly collected by...

Photo gallery of data set

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In...

Mechanisms that decrease niche overlap, whether dietary, spatial, or temporal, are important in facilitating the coexistence of sympatric competitors. Since predators commonly partition resources via temporal segregation, we investigated whether it plays a significant role in mediating the coexistence of four common boreal predators: black bear (Ur...

For arboreal primates, ground use may increase dispersal opportunities, tolerance to habitat change, access to ground-based resources, and resilience to human disturbances, and so has conservation implications. We collated published and unpublished data from 86 studies across 65 localities to assess titi monkey (Callicebinae) terrestriality. We exa...

Free download link: https://authors.elsevier.com/a/1ZfOn,Q4YJNLg0 The dynamic interaction between animals and plants through frugivory and seed dispersal is one of several ecological processes that modulates tropical biodiversity. Here we evaluated the potential role of a highly-frugivorous Neotropical primate, the black-fronted titi monkey (Calli...

Protected areas can mediate negative effects of habitat loss and human-related pressures on key ecological groups. However, different protected area categories can vary substantially in their degree of enforcement, which may ensure different levels of effectiveness for biodiversity protection. Because little attempt has been made to quantify this,...

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across...

Primates employ many strategies to deal with the costs of reproduction. While income breeders exploit the food available in their environment during lactation, the most costly phase of reproduction, capital breeders tend to store energy for use in the period. We analyzed the relationship between resource availability and lactation in Callicebus coi...

Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate specie...

Stereotypies are frequently associated with sub-optimal captive environments and are used as welfare indicators. However, susceptibility to stereotypy can vary across individuals of the same group. As such, identifying which individuals are more susceptible to this behaviour may be helpful in managing this issue. We have investigated which sex-age...

Mechanisms that decrease niche overlap in at least one of its dimensions (i.e., spatial, temporal, or dietary) tend to facilitate coexistence of similar, sympatric species. We investigated whether temporal or dietary segregation plays a significant role in the coexistence of Neotropical small felids. In addition, we examined the role of prey activi...

The costs imposed by predation may result in behavioral adaptations to reduce mortality risk, including the choice and use of sleeping sites. The threat of predation, however, is rarely the sole force shaping sleeping site choice, which is likely to reflect other factors such as foraging needs as well. Here we describe the use of sleeping sites by...

Disentangling the role of competition in regulating the distribution of sympatric species can be difficult because species can have different habitat preferences or time use that introduce non-random patterns that are not related to interspecific interactions. We adopted a multi-step approach to systematically incorporate habitat preferences while...

Figure A. Relationship between occupancy probability and elevation for two sympatric Neotropical tinamous, the brown tinamou (Crypturellus obsoletus) and tataupa tinamou (C. tataupa) in a continuous seasonal Atlantic Forest remnant Brazil. Figure B. Influence of the analyzed climate and habitat variables in the detection probabilities of two sympat...

Birds may use urban parks as shelter and refuge, contributing with numerous ecosystem services upon which humans and other organisms depend on. To safeguard these services, it is important that bird communities of urban environments hold some degree of resilience, which refers to the capacity of a system to absorb disturbances and changes, while ma...

Frugivores are key components of Neotropical forests, regulating plant communities, forest structure, and plant diversity; however, they are highly threatened by human impacts worldwide. To effectively conserve this group, maintain their ecological functions, and plan management actions or establish future protected areas, we need to gather informa...

Many primates have to cope with temporal scarcity in food availability that shapes their foraging strategies. Here we investigated the changes in diet, activity, and ranging behavior of a group of black-fronted titi monkeys (Callicebus nigrifrons) according to the availability of the main high nutritional density item of their diet and the foraging...

Accurate measures of animal population densities are essential to assess their status, demography, and answer ecological questions. Among several methods proposed to collect abundance data, line transect sampling is used the most. The assumptions required to obtain accurate density estimates through this method, however, are rarely met when studyin...

Pitheciids are known for their frugivorous diets, but there has been no broad-scale comparison of fruit genera used by these primates that range across five geographic regions in South America. We compiled 31 fruit lists from data collected from 18 species (three Cacajao, six Callicebus, five Chiropotes, and four Pithecia) at 26 study sites in six...