Thomas Breuer

World Wide Fund For Nature, Germany - Berlin · Africa & South America

Understanding the ecological factors influencing African forest elephant (Loxodonta cyclotis) abundance and distribution is crucial for their conservation management in Central Africa. Dung surveys have been conducted at the landscape scale and confirmed the overwhelming impact of anthropogenic activities on forest elephants. We present results fro...

With a drastic decrease in their populations over the last decades, forest elephants Loxodonta cyclotis are facing increasing human pressure. Their decline will have serious ecological consequences, as they are key actors in shaping ecosystems. Whilst timber concessions host many mammal species, the interactions between selective logging and forest...

Estimating the richness and abundance of animal species remains central to any conservation strategy of a given area. In remote and challenging environments such as tropical forests, camera traps have proven to be successful in documenting secretive wildlife communities compared to other survey methods, as they allow continuous monitoring without t...

Human-wildlife conflicts are ancient, but they are posing an increasing challenge for conservation managers across Africa. Human-wildlife conflicts can lead to a loss of biodiversity and a substantial decline in human well-being, most often for people living near protected areas . Avoiding or solving these conflicts are key issues for both protec...

Highlights • Animal movement heuristics should vary depending on the level of cognition involved. • Gorilla movements between feeding sites do not correspond to a Lévy walk. • Gorillas plan their foraging movements using spatiotemporal memory. • Cognitive foraging by gorillas occurs during both the high- and low-frugivory seasons. • Animal mo...

This chapter presents the distribution, abundance patterns and trends of African buffalo in the 38 countries of its distribution area based on recent aerial and ground census data and feedback from field experts. For the period 2001–2021, we collected abundance data from 163 protected areas or complexes of protected areas and presence data from 711...

Objectives: Several theories have been proposed to explain the impact of ecological conditions on differences in life history variables within and between species. Here we compare female life history parameters of one western lowland gorilla population (Gorilla gorilla gorilla) and two mountain gorilla populations (Gorilla beringei beringei). Mat...

Carnivores are threatened across Sub-Saharan Africa mostly due to retaliatory killing by people, the loss of prey species and their habitats. Due to their food and space requirements, they regularly come into conflict with humans. In many regions, information about carnivore occurrence and human-carnivore conflict remains poorly known particularly...

Understanding what are the proximate mechanisms shaping species’ space-use dynamics, and at which scale, can provide insights into species socio-ecology. This is crucial information for both applied (e.g., conservation) and theoretical questions (e.g. individuals’ coexistence/segregation). Yet, longitudinal views of the space-use dynamics of animal...

Long-term studies of population dynamics can provide insights into life history theory, population ecology, socioecology, conservation biology and wildlife management. Here we examine 25 years of population dynamics of western gorillas at Mbeli Bai, a swampy forest clearing in Nouabalé-Ndoki National Park, the Republic of Congo. The Mbeli populatio...

The earliest stone tool types, sharp flakes knapped from stone cores, are assumed to have played a crucial role in human cognitive evolution. Flaked stone tools have been observed to be accidentally produced when wild monkeys use handheld stones as tools. Holding a stone core in hand and hitting it with another in the absence of flaking, free hand...

Studies of the evolutionary relationships among gorilla populations using autosomal and mitochondrial sequences suggest that male-mediated gene flow may have been important in the past, but data on the Y-chromosomal relationships among the gorilla subspecies are limited. Here, we genotyped blood and noninvasively collected fecal samples from 12 cap...

Tourism is both a promising and a fragile economic sector, vulnerable to political events and health crises such as Covid-19. In the absence of sectoral insurance and employment policies worthy of the name, States and private partners must set up tourism support funds and mutual insurance companies that enable the most fragile structures and...

Small-scale comparisons help us to understand how habitat features and food availability impact primate abundance. This is particularly useful at sites without human impacts, as it allows for the investigation of the natural factors influencing nesting patterns and great ape abundance. We provide a small-scale study of sympatric great ape nests in...

Les conflits entre l’homme et la faune sauvage sont très anciens mais ils posent de nos jours un défi croissant aux responsables de la conservation et ce, à travers toute l’Afrique (Lamarque et al., 2009; Nyhus, 2016; Shaffer et al., 2019). Ces conflits peuvent entraîner une perte de la biodiversité et un déclin important du bien-être humain, le pl...

Le tourisme est devenu une importante industrie à l’échelle mondiale, participant à hauteur de 10,3 % du PIB mondial en 2019 (Produit Intérieur Brut ; WTTC, 2020). Il contribue fortement à la création d’emplois dans certains pays, en particulier pour les femmes, les jeunes, les travailleurs migrants, les communautés rurales et les populations autoc...

Is it possible to slow the rate of ageing, or do biological constraints limit its plasticity? We test the ‘invariant rate of ageing’ hypothesis, which posits that the rate of ageing is relatively fixed within species, with a collection of 39 human and nonhuman primate datasets across seven genera. We first recapitulate, in nonhuman primates, the hi...

Food calls are widespread across many mammal and bird species, but the reasons of this adaptive success are not yet fully understood. Using data from four habituated groups of western gorillas (Gorilla gorilla) in Central Africa, we investigated the possible influence of ecological (food type and quantity) and social factors (presence, arrival and...

Accurate and ecologically relevant wildlife population estimates are critical for species management. One of the most common survey methods for forest mammals – line transects for animal sign with distance sampling – has assumptions regarding conversion factors that, if violated, can induce substantial bias in abundance estimates. Specifically, for...

Characterizing animal dispersal patterns and the rational behind individuals’ transfer choices is a long-standing question of interest in evolutionary biology. In wild western gorillas (Gorilla gorilla), a one-male polygynous species, previous genetic findings suggested that, when dispersing, females might favor groups with female kin to promote co...

Unsustainable hunting of bushmeat has dramatic impacts on ecological processes and people's livelihoods. Unfortunately, there is often a strong controversy regarding the sustainability of duiker hunting due to their continued presence in bushmeat markets, on the one hand, and the predictions of sustainable harvest models for duiker abundance, on th...

Is it possible to slow the rate of aging, or do biological constraints limit its plasticity? We test this ‘invariant rate of aging’ hypothesis with an unprecedented collection of 39 human and nonhuman primate datasets across seven genera. We first recapitulate, in nonhuman primates, the highly regular relationship between life expectancy and lifesp...

Primate populations are declining throughout tropical Africa. Great apes are threatened from extinction despite the existence of wildlife laws that fully protect them in their range states. But, due to a lack of knowledge and understanding of these laws, they remain largely ineffective. There is, therefore, a crucial need to improve awareness of wi...

In many social species, after the alpha male has been replaced or the group disintegrates, a female’s infant is at risk of infanticide by a male. Female gorillas have developed the rare strategy of secondary dispersal in which they transfer between reproductive groups during the limited time period between weaning an infant and conceiving the next...

The SARS-CoV-2 virus and COVID-19 illness are driving a global crisis. Governments have responded by restricting human movement, which has reduced economic activity. These changes may benefit biodiversity conservation in some ways, but in Africa, we contend that the net conservation impacts of COVID-19 will be strongly negative. Here, we describe h...

Evaluating the factors influencing the patterns of female dispersal in mammals is critical to understanding its importance for male and female reproductive strategies and the evolution of social systems. In western lowland gorillas, females emigrate from their natal group (natal dispersal) but also disperse between groups multiple times in their li...

In group-living mammals, individual efforts to maximize reproductive success result in conflicts and compromises between the sexes. Females utilize counterstrategies to minimize the costs of sexual coercion by males, but few studies have examined the effect of such behaviors on female reproductive success. Secondary dispersal by females is rare amo...

Modern human societies show hierarchical social modularity (HSM) in which lower-order social units like nuclear families are nested inside increasingly larger units. It has been argued that this HSM evolved independently and after the chimpanzee-human split due to greater recognition of, and bonding between, dispersed kin. We used network modularit...

http://advances.sciencemag.org/cgi/content/full/4/4/eaar2964/DC1

Unraveling the relationship between the unusual feeding behaviors and the nutritional intake of endangered species may provide crucial information for understanding species response to habitat unpredictable changes. Primates occasionally re‐ingest fruit seeds alongside ingestion of feces, a behavior called coprophagy. The nutritional benefit is one...

We present a range-wide assessment of sympatric western lowland gorillas Gorilla gorilla gorilla and central chimpanzees Pan troglodytes troglodytes using the largest survey data set ever assembled for these taxa: 59 sites in five countries surveyed between 2003 and 2013, totaling 61,000 person-days of fieldwork. We used spatial modeling to investi...

We present the first cross continental comparison of the flowering and fruiting phenology of tropical forests across Africa. Flowering events of 5,446 trees from 196 species across 12 sites, and fruiting events of 4,595 trees from 191 species, across 11 sites were monitored over periods of 6 to 29 years, and analysed to describe phenology at the co...

Zoos and aquariums undoubtably have an important role to play in supporting species conservation through a diverse range of activities, including public awareness and financial support of field-conservation projects. Charismatic megafauna, such as gorillas Gorilla spp, play a crucial role as flagship species in their range countries, acting as amba...

Objectives: All human populations display a right-biased handedness. Nonetheless, if studies on western populations are plenty, investigations of traditional populations living at subsistence levels are rare. Yet, understanding the geographical variation of phenotypes of handedness is crucial for testing evolutionary hypotheses. We aimed to provid...

Overexploitation is one of the main pressures driving wildlife closer to extinction, yet broad-scale data to evaluate species’ declines are limited. Using African pangolins (Family: Pholidota) as a case study, we demonstrate that collating local-scale data can provide crucial information on regional trends in exploitation of threatened species to i...

Names Genus: Potamochoerus Gray, 1854 Species: Potamochoerus porcus (Linnaeus, 1758) Names in other languages: French: Potamochère roux, Potamochère d’Afrique; German: Pinselohrschwein; Spanish: Potamocero rojo; Italian: Potamocero rosso, Potamocero di fiume; Afrikaans: Bosvark; kiSwahili: Nguruwe; Lingala in Congo: Ngulu; Lingala in DRC: Nsombo; T...

Applying environmental education in primate range countries is an important long-term activity to stimulate pro-conservation behavior. Within captive settings, mega-charismatic species, such as great apes are often used to increase knowledge and positively influence attitudes of visitors. Here, we evaluate the effectiveness of a short-term video an...

Human–elephant conflict is a common conservation problem throughout Africa, but poorly studied where forest elephants (Loxodonta cyclotis) occur. Here, we investigated people's perceptions towards the impact of elephants around Nouabalé-Ndoki National Park, northern Congo. We aimed to understand the perceptual differences amongst residents of four...

An assessment of local attitudes towards conservation can guide wildlife managers in the effective application of measurements to improve these perceptions. Here we conducted a quantitative questionnaire survey around a protected area in northern Congo surveying 314 households living in four villages around the Nouabalé-Ndoki National Park. We inve...

When mothers continue to support their offspring beyond infancy, they can influence the fitness of those offspring, the strength of social relationships within their groups, and the life-history traits of their species. Using up to 30 years of demographic data from 58 groups of gorillas in two study sites, this study extends such findings by showin...

A participatory landscape monitoring initiative was introduced in the Sangha Tri-National landscape at the frontier of Cameroon, the Republic of Congo and the Central African Republic in 2006. The initiative allowed a broad range of stakeholders, called the Sangha Group, to monitor changes in local peoples' livelihoods and the environment. The grou...

Buffalo showed high site fidelity to open areas, including forest clearings. Forest buffalo herds (mean 12 ind. ± SD; range 3-24) were much smaller than records of savanna buffalo herds (mean 350 ind. ± SD; range 12-1500>), but also showed frequently fission-fusion patterns. Data from Mbeli Bai collected from 2006 to 2015 confirm a stable presence...

Link: http://www.iucnredlist.org/details/9406/0

The ability to accurately measure morphological characteristics of wild primates in the field is challenging, yet critical for understanding fundamental aspects of their biology and behavior. Recent studies have shown that digital photogrammetry can be used to non-invasively measure morphological traits of wild primates, as it allows for the determ...

Many nonhuman primates produce food-associated vocalizations upon encountering or ingesting particular food. Concerning the great apes, only food-associated vocalizations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) have been studied in detail, providing evidence that these vocalizations can be produced flexibly in relation to a vari...

Kusu humming (Pteleopsis hylodendron). (WAV)

Mobimba singing (Gilbertiodendron dewevrei). (WAV)

Balema singing (Gilbertiodendron dewevrei). (WAV)

Kusu humming (Pteleopsis hylodendron). (WAV)

The conservation of tropical forest carbon stocks offers the opportunity to curb climate 43 change by reducing greenhouse gas emissions from deforestation and simultaneously conserve 44 biodiversity. However, there has been considerable debate about the extent to which carbon 45 storage will provide benefits to biodiversity in part because whether...

Poaching has devastated forest elephant populations (Loxodonta cyclotis), and their habitat is dramatically changing. The long-term effects of poaching and other anthropogenic threats have been well studied in savannah elephants (Loxodonta africana), but the impacts of these changes for Central Africa's forest elephants have not been discussed. We...

Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n =...

When mothers continue to support their offspring beyond infancy, they can influence the fitness of those offspring, the strength of social relationships within their groups, and the life-history traits of their species. Using up to 30 years of demographic data from 58 groups of gorillas in two study sites, this study extends such findings by showin...

When mothers continue to support their offspring beyond infancy, they can influence the fitness of those offspring, the strength of social relationships within their groups, and the life-history traits of their species. Using up to 30 years of demographic data from 58 groups of gorillas in two study sites, this study extends such findings by showin...

The conservation of tropical forest carbon stocks offers the opportunity to curb climate change by reducing greenhouse gas emissions from deforestation and simultaneously conserve biodiversity. However, there has been considerable debate about the extent to which carbon storage will provide benefits to biodiversity in part because whether forests t...

Sexual coercion and courtship are possible explanations for why male primates may direct agonistic behavior towards females. If so, then in species where females exhibit mate choice by transferring between males: (a) females who are not lactating (potential migrants) should receive more agonistic behavior than other females, (b) males should exhibi...

Unsustainable exploitation of wild animals is one of the greatest threats to biodiversity and to millions of people depending on wild meat for food and income. The international conservation and development community has committed to implementing plans for sustainable use of natural resources and has requested development of monitoring systems of b...