Urbanization Impacts Top Predators and Alters Biotic Interactions in Predator-Prey-Mutualistic Communities of Urban Dry Grasslands.

Urbanization as a major driver of global change modifies biodiversity patterns and the abundance and interactions among species or functional species groups. For example, urbanization can negatively impact both predator-prey and mutualistic relationships. However, empirical studies on how urbanization modifies biotic, particularly multitrophic, interactions are still limited.

Spatio-temporal metapopulation trends: The coconut crabs of Zanzibar.

Species experience a variety of environmental and anthropogenic conditions across their ranges leading to spatial variation in population dynamics. Understanding population dynamics under different conditions is important but it is challenging to allocate limited effort to spatial and temporal subpopulation monitoring. Using GLMMs, we analyze survey data of a metapopulation of coconut crabs spanning 7 years and 15 sites in and near the Pemba archipelago, Zanzibar, to estimate trends in population size (based on catch per unit effort), weight and sex ratio at the meta- and subpopulation level and investigate anthropogenic drivers of these trends.

First record of a mixed species association between Hatinh langur () and red-shanked douc ().

In primates, mixed species associations are not common occurrences, and have been linked to both ecological and anthropogenic factors. We present camera-trapping records of a mixed association between two primates, the Hatinh langur () and red-shanked douc () and discuss possible hypotheses for this occurrence. To our knowledge, this is the first evidence of such an association in the wild of these two threatened primates, and thus contributes to our limited ecological knowledge of the species.

Trophic position determines the persistence of neotropical understory birds after forest disturbance.

Habitat loss and degradation are key drivers of the current biodiversity crisis. Most research focuses on the question of which traits allow species to persist in degraded habitats. We asked whether a species' trophic position or niche width influences the resilience of species in degraded habitats and to what extent habitat degradation affects trophic interactions between species.

Resource asynchrony and landscape homogenization as drivers of virulence evolution: The case of a directly transmitted disease in a social host.

Throughout the last decades, the emergence of zoonotic diseases and the frequency of disease outbreaks have increased substantially, fuelled by habitat encroachment and vectors overlapping with more hosts due to global change. The virulence of pathogens is one key trait for successful invasion. In order to understand how global change drivers such as habitat homogenization and climate change drive pathogen virulence evolution, we adapted an established individual-based model of host-pathogen dynamics.

Response of pollinator taxa to fire is consistent with historic fire regimes in the Sierra Nevada and mediated through floral richness.

Many fire-prone forests are experiencing wildfires that burn outside the historical range of variation in extent and severity. These fires impact pollinators and the ecosystem services they provide, but how the effects of fire are mediated by burn severity in different habitats is not well understood. We used generalized linear mixed models in a Bayesian framework to model the abundance of pollinators as a function of burn severity, habitat, and floral resources in post-fire, mid-elevation, conifer forest, and meadow in the Sierra Nevada, California.

Reading the signs: Camera-trapping provides new insights on scent marking in the large-antlered muntjac ().

We present evidence of scent marking in the large-antlered muntjac (). Given the importance of scent marking in individual recognition among ungulates, this behavior may serve to communicate the fitness cost of antagonistic interactions among rival males and could serve as a mechanism for mate assessment among females.

How do terrestrial wildlife communities respond to small-scale plantations embedded in harvested tropical forest?

To offset the declining timber supply by shifting towards more sustainable forestry practices, industrial tree plantations are expanding in tropical production forests. The conversion of natural forests to tree plantation is generally associated with loss of biodiversity and shifts towards more generalist and disturbance tolerant communities, but effects of mixed-landuse landscapes integrating natural and plantation forests remain little understood. Using camera traps, we surveyed the medium-to-large bodied terrestrial wildlife community across two mixed-landuse forest management areas in Sarawak, Malaysia Borneo which include areas dedicated to logging of natural forests and adjacent planted forests.

Evidence for a male-biased sex ratio in the offspring of a large herbivore: The role of environmental conditions in the sex ratio variation.

Numerous studies have examined whether the primary and/or secondary sex ratio in mammals, including humans, deviates from an equilibrium of 1:1. Although effect size in the sex ratio variation is expected to be low, a large sample size allows the identification of even small deviations from parity. In this study, we investigated whether the sex ratio of roe deer () offspring at birth approaches parity, using a large data set from roe deer offspring tagged in Baden-Württemberg (Germany, 1972-2019,  = 12,437).

Small mammal responses to fire severity mediated by vegetation characteristics and species traits.

The frequency of large, high-severity "mega-fires" has increased in recent decades, with numerous consequences for forest ecosystems. In particular, small mammal communities are vulnerable to post-fire shifts in resource availability and play critical roles in forest ecosystems. Inconsistencies in previous observations of small mammal community responses to fire severity underscore the importance of examining mechanisms regulating the effects of fire severity on post-fire recovery of small mammal communities.

Environmental DNA metabarcoding primers for freshwater fish detection and quantification: In silico and in tanks.

Environmental DNA (eDNA) techniques refer to utilizing the organisms' DNA extracted from environment samples to genetically identify target species without capturing actual organisms. eDNA metabarcoding via high-throughput sequencing can simultaneously detect multiple fish species from a single water sample, which is a powerful tool for the qualitative detection and quantitative estimates of multiple fish species. However, sequence counts obtained from eDNA metabarcoding may be influenced by many factors, of which primer bias is one of the foremost causes of methodological error.

Noninvasively measured immune responses reflect current parasite infections in a wild carnivore and are linked to longevity.

Host immune defenses are important components of host-parasite interactions that affect the outcome of infection and may have fitness consequences for hosts when increased allocation of resources to immune responses undermines other essential life processes. Research on host-parasite interactions in large free-ranging wild mammals is currently hampered by a lack of verified noninvasive assays. We successfully adapted existing assays to measure innate and adaptive immune responses produced by the gastrointestinal mucosa in spotted hyena () feces, including enzyme-linked immunosorbent assays (ELISAs), to quantify fecal immunoglobulins (total IgA, total IgG) and total fecal O-linked oligosaccharides (mucin).

Movement can mediate temporal mismatches between resource availability and biological events in host-pathogen interactions.

Global change is shifting the timing of biological events, leading to temporal mismatches between biological events and resource availability. These temporal mismatches can threaten species' populations. Importantly, temporal mismatches not only exert strong pressures on the population dynamics of the focal species, but can also lead to substantial changes in pairwise species interactions such as host-pathogen systems.

Individual dietary specialization in a generalist predator: A stable isotope analysis of urban and rural red foxes.

Some carnivores are known to survive well in urban habitats, yet the underlying behavioral tactics are poorly understood. One likely explanation for the success in urban habitats might be that carnivores are generalist consumers. However, urban populations of carnivores could as well consist of specialist feeders.

Evidence of a spatial auto-correlation in the browsing level of four major European tree species.

The contribution of spatial processes to the spatial patterns of ecological systems is widely recognized, but spatial patterns in the ecology of plant-herbivore interactions have rarely been investigated quantitatively owing to limited budget and time associated with ecological research. Studies of the level of browsing on various tree species reported either no spatial auto-correlation or a small effect size. Further, the effects of disturbance events, such as hurricanes, which create large forest openings on spatial patterns of herbivory are not well understood.

Mate choice, reproductive success and inbreeding in white rhinoceros: New insights for conservation management.

Improving our sparse knowledge of the mating and reproductive behaviour of white rhinoceros ( Burchell, 1817) is essential for the effective conservation of this iconic species. By combining morphological, physiological and habitat data with paternity assignments of 104 known mother-offspring pairs collected over a period of 13 years, we provide the most comprehensive analysis of the mating system in this species. We show that while the overall mating system was promiscuous, and both males and females produced more offspring when mating with several partners, half of all females with multiple offspring were monogamous.

Modeling the emergence of migratory corridors and foraging hot spots of the green sea turtle.

Environmental factors shape the spatial distribution and dynamics of populations. Understanding how these factors interact with movement behavior is critical for efficient conservation, in particular for migratory species. Adult female green sea turtles, , migrate between foraging and nesting sites that are generally separated by thousands of kilometers.

Parasite infections in a social carnivore: Evidence of their fitness consequences and factors modulating infection load.

There are substantial individual differences in parasite composition and infection load in wildlife populations. Few studies have investigated the factors shaping this heterogeneity in large wild mammals or the impact of parasite infections on Darwinian fitness, particularly in juveniles. A host's parasite composition and infection load can be shaped by factors that determine contact with infective parasite stages and those that determine the host's resistance to infection, such as abiotic and social environmental factors, and age.

Circadian rhythms enable efficient resource selection in a human-modified landscape.

Animals access resources such as food and shelter, and acquiring these resources has varying risks and benefits, depending on the suitability of the landscape. Some animals change their patterns of resource selection in space and time to optimize the trade-off between risks and benefits. We examine the circadian variation in resource selection of swamp wallabies () within a human-modified landscape, an environment of varying suitability.

Foraging ecology of Eurasian lynx populations in southwest Asia: Conservation implications for a diet specialist.

Intraspecific variation in key traits of widespread species can be hard to predict, if populations have been very little studied in most of the distribution range. Asian populations of the Eurasian lynx (), one of the most widespread felids worldwide, are such a case in point. We investigated the diet of Eurasian lynx from feces collected Mediterranean, mixed forest-steppe, and subalpine ecosystems of Turkey.

Migratory bats are attracted by red light but not by warm-white light: Implications for the protection of nocturnal migrants.

The replacement of conventional lighting with energy-saving light emitting diodes (LED) is a worldwide trend, yet its consequences for animals and ecosystems are poorly understood. Strictly nocturnal animals such as bats are particularly sensitive to artificial light at night (ALAN). Past studies have shown that bats, in general, respond to ALAN according to the emitted light color and that migratory bats, in particular, exhibit phototaxis in response to green light.

Coping with intrasexual behavioral differences: Capture-recapture abundance estimation of male cheetah.

Population estimates are a fundamental requirement of ecology and conservation. While capture-recapture models are an established method for producing such estimates, their assumption of homogeneous capture probabilities is problematic given that heterogeneity in individual capture probability is inherent to most species. Such variation must be accounted for by abundance models; otherwise, biased estimates are risked.

Social status mediates the fitness costs of infection with canine distemper virus in Serengeti spotted hyenas.

The extent to which the fitness costs of infection are mediated by key life-history traits such as age or social status is still unclear. Within populations, individual heterogeneity in the outcome of infection is the result of two successive processes; the degree of contact with the pathogen (exposure) and the immune response to infection. In social mammals, because individuals holding high social status typically interact more frequently with group members, they should be more often in contact with infected individuals than those of low social status.

Recolonizing gray wolves increase parasite infection risk in their prey.

The recent recolonization of Central Europe by the European gray wolf () provides an opportunity to study the dynamics of parasite transmission for cases when a definitive host returns after a phase of local extinction. We investigated whether a newly established wolf population increased the prevalence of those parasites in ungulate intermediate hosts representing wolf prey, whether some parasite species are particularly well adapted to wolves, and the potential basis for such adaptations. We recorded species richness in wolves and prevalence in ungulates harvested in study sites with and without permanent wolf presence in Germany using microscopy and DNA metabarcoding.