Mammal responses to global changes in human activity vary by trophic group and landscape

Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human-wildlife interactions along gradients of human influence.

Underlying and proximate drivers of biodiversity changes in Mesoamerican biosphere reserves

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.

Habitat use and activity patterns of ungulates in a tropical rainforest of southern México

Baird’s tapir (Tapirella bairdii), white-lipped peccary (Tayassu pecari), and collared peccary (Dicotyles tajacu) sympatrically occur in the Lacandon Forest of Chiapas, México. These species contribute to maintain ecosystem dynamics through herbivory, seed dispersal, and seed predation, constituting important prey for large carnivores and hunters. We analyzed activity patterns and habitat use of the three focal species to assess the degree of temporal and spatial habitat segregation among them in Montes Azules Biosphere Reserve (REBIMA) and surrounding communities. Between February and October 2015 we deployed camera-traps during 8,463 camera-trap days to estimate the presence and activity of tapirs and peccaries in two habitat types: “conserved” (REBIMA), and “transformed” (community forests; AFC). Habitat use and activity patterns of tapirs and peccaries were assessed through logistic regression models. We found that Baird’s tapir was almost exclusively nocturnal with a trend towards crepuscular activity, while both peccary species were diurnal, therefore showing a high daily temporal segregation from the tapir. Both peccary species were similarly active in the two study sites, while tapirs were more active in continuous forest within the protected area. The occurrence of tapirs and white-lipped peccaries depended on the presence and proximity of water sources and roads. Our results suggest that spatial segregation of the habitat allows coexistence of both peccary species in the study area. AFC have potential for maintaining populations of tapirs and peccaries in the Lacandon Forest. Conserving these forests by local communities is essential to ensure the persistence of these mammals.

Long-term trends in a forest ungulate community: park establishment increases numbers, but poaching is a constant threat

Deforestation represents one of the greatest threats to tropical forest mammals, and the situation is greatly exacerbated by bushmeat hunting. To construct informed conservation plans, information must be gathered about responses to habitat degradation, regeneration, and hunting over a sufficiently long period to allow demographic responses. We quantified changes in the abundance of three commonly occurring ungulate species (i.e., bushbuck, Tragelaphus scriptus; red duiker, Cephalophus sp.; blue duiker, Cephalophus monticola) at eight sites in Kibale National Park, Uganda (old growth=3; logged=3; regenerating=2) for 23 years. Changes in abundance (363 surveys totaling 1 450 km) were considered in regard to the park's management strategy, regional economic indicators, and estimates of illegal hunting. Bushbuck abundance increased in old-growth and logged forests from 1996 to 2009, and then oscillated around this level or declined. Duiker abundance demonstrated a similar pattern, but abundance in the old-growth forests showed a general increase from 1996 to present day. Duiker abundance in the logged forests exhibited an early increase, but subsequent oscillation. Poaching signs per patrol have remained stable over the last decade, despite increases in the size of the surrounding population, cost of living, and cost of schooling, thus reflecting successful efforts in conservation education and enforcement. Our study highlights the positive impact of park establishment, patrol, and conservation efforts on ungulate populations and shows the adaptability of forest mammal populations to different management schemes.

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

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 Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.

Correction to: Towards the restoration of the Mesoamerican Biological Corridor for large mammals in Panama: comparing multi-species occupancy to movement models

[This corrects the article DOI: 10.1186/s40462-019-0186-0.].

Effectiveness of Panama as an intercontinental land bridge for large mammals

Habitat fragmentation is a primary driver of wildlife loss, and establishment of biological corridors is a common strategy to mitigate this problem. A flagship example is the Mesoamerican Biological Corridor (MBC), which aims to connect protected forest areas between Mexico and Panama to allow dispersal and gene flow of forest organisms. Because forests across Central America have continued to degrade, the functioning of the MBC has been questioned, but reliable estimates of species occurrence were unavailable. Large mammals are suitable indicators of forest functioning, so we assessed their conservation status across the Isthmus of Panama, the narrowest section of the MBC. We used large-scale camera-trap surveys and hierarchical multispecies occupancy models in a Bayesian framework to estimate the occupancy of 9 medium to large mammals and developed an occupancy-weighted connectivity metric to evaluate species-specific functional connectivity. White-lipped peccary (Tayassu pecari), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), white-tailed deer (Odocoileus virginianus), and tapir (Tapirus bairdii) had low expected occupancy along the MBC in Panama. Puma (Puma concolor), red brocket deer (Mazama temama), ocelot (Leopardus pardalis), and collared peccary (Pecari tajacu), which are more adaptable, had higher occupancy, even in areas with low forest cover near infrastructure. However, the majority of species were subject to ≥1 gap that was larger than their known dispersal distances, suggesting poor connectivity along the MBC in Panama. Based on our results, forests in Darien, Donoso-Santa Fe, and La Amistad International Park are critical for survival of large terrestrial mammals in Panama and 2 areas need restoration.

Towards the restoration of the Mesoamerican Biological Corridor for large mammals in Panama: comparing multi-species occupancy to movement models

BACKGROUND

Habitat fragmentation is a primary driver of wildlife loss, and the establishment of biological corridors is a conservation strategy to mitigate this problem. Identifying areas with high potential functional connectivity typically relies on the assessment of landscape resistance to movement. Many modeling approaches exist to estimate resistance surfaces but to date only a handful of studies compared the outputs resulting from different methods. Moreover, as many species are threatened by fragmentation, effective biodiversity conservation requires that corridors simultaneously meet the needs of multiple species. While many corridor planning initiatives focus on single species, we here used a combination of data types and analytical approaches to identify and compare corridors for several large mammal species within the Panama portion of the Mesoamerican Biological Corridor.

METHODS

We divided a large mammal assemblage into two groups depending on the species sensitivity to habitat disturbance. We subsequently used cost-distance methods to produce multi-species corridors which were modeled on the basis of (i) occupancy of nine species derived from camera trapping data collected across Panama, and (ii) step selection functions based on GPS telemetry data from white-lipped peccary Tayassu pecari, puma Puma concolor, and ocelot Leopardus pardalis. In addition to different data sources and species groups, we also used different transformation curves to convert occupancy and step-selection results into landscape resistance values.

RESULTS

Corridors modeled differed between sensitive and tolerant species, between the data sets, and between the transformation curves. There were more corridors identified for tolerant species than for sensitive species. For tolerant species, several corridors developed with occupancy data overlapped with corridors produced with step selection functions, but this was not the case for sensitive species.

CONCLUSION

Our study represents the first comparison of multispecies corridors parametrized with step selection functions versus occupancy models. Given the wide variability in output corridors, our findings underscore the need to consider the ecological requirements of several species. Our results also suggest that occupancy models can be used for estimating connectivity of generalist species. Finally, this effort allowed to identify important corridors within the MBC (i) at a country scale and (ii) for several species simultaneously to accurately inform the local authorities in conservation planning. The approach we present is reproducible in other sites and/or for other species.

Spider Monkey (Ateles geoffroyi) Travel to Resting Trees in a Seasonal Forest of the Yucatan Peninsula, Mexico

Resting by primates is considered an understudied activity, relative to feeding or moving, despite its importance in physiological and time investment terms. Here we describe spider monkeys' (Ateles geoffroyi) travel from feeding to resting trees in a seasonal tropical forest of the Yucatan Peninsula. We followed adult and subadult individuals for as long as possible, recording their activities and spatial location to construct travel paths. Spider monkeys spent 44% of the total sampling time resting. In 49% of the cases, spider monkeys fed and subsequently rested in the same tree, whereas in the remaining cases they travelled a mean distance of 108.3 m. Spider monkeys showed high linear paths (mean linearity index = 0.77) to resting trees when they travelled longer distances than their visual field, which suggests travel efficiency and reduced travel cost. Resting activity is time consuming and affects the time available to search for food and engage in social interactions.

Patch depletion behavior differs between sympatric folivorous primates

Food competition in group-living animals is commonly accepted as a critical determinant of foraging strategies and social organization. Here we examine food patch depletion behavior in a leaf-eating (folivorous) primate, the guereza (Colobus guereza). Snaith and Chapman (2005) studied the sympatric folivorous red colobus (Procolobus rufomitratus), which shares many food resources with the guereza. They determined that red colobus deplete the patches (feeding trees) they use, while we found contrary evidence for guerezas using the same methods. We found that the time guerezas spent feeding in a patch was affected by neither tree size, an indicator of food abundance, nor the size of the feeding group, an indicator of feeding competition. For their principal food item (young leaves), intake rate remained constant and coincided with a decrease in the distance moved to find food within a patch, implying that guerezas do not deplete patches. This points to a fundamental difference in the use of food by guerezas and red colobus, which may be linked to the large difference in their group sizes and/or to a disparity in their digestive physiologies. However, further analyses revealed that the number of feeders within a patch did not affect patch depletion patterns in either species, leaving the potential for a physiological basis as the most plausible explanation. Our research highlights the need for a more critical examination of folivorous primate feeding ecology and social behavior, as all folivorous primates are typically lumped into a single category in socioecological models, which may account for conflicting evidence in the literature.

La dieta de los pecaries (Pecari tajacu y Tayassu pecari) en la región de Calakmul, Campeche, México

RESUMEN: Se determinaron los componentes principales y su variación estacional de la dieta del Tayassu pecari y Pecari  tajacu en la región de Calakmul, Campeche, durante el período de mayo de 2005 a julio de 2006.  Del análisis de 22 estómagos de P. tajacu, se encontró que los componentes más abundantes durante el año fueron los frutos (57.9%) y las hojas (30.1%).  De las 37 especies vegetales consumidas por P. tajacu las principales fueron: Brosimum alicastrum, Manilkara zapota, Pipper amalago, Zea maiz y una más no identificada.  Se analizaron nueve estómagos y 16 excretas de T. pecari, encontrando que consume 41 especies vegetales donde el componente más abundante en contenidos estomacales y excretas fueron los frutos  con 81.2% y 66.8% respectivamente.  Las principales especies consumidas por T. pecari fueron B. alicastrum, Chamaedorea sp, M. zapota, Mimosa sp, P. amalago y una no identificada. Ambos pecaríes compartieron 32 especies y sus nichos alimenticios no se sobrepusieron significativamente (Qjk= 0.58).  Las dos especies de pecaríes juegan un papel de predadores de semillas de las especies de las cuales se alimentan.PALABRAS CLAVE: Calakmul, dieta, coexistencia, Tayassuidae, Tayassu pecari y Pecari tajacu.ABSTRACT:We determined the main components as well as seasonal differences on the diet of Tayassu pecari and Pecari tajacu in the Calakmul Region in Southern Mexico. Analyses of 22 stomach contents of P. tajacu revealed that this species consume more fruits (57.9 %) than leaves (30.1). From 37 plant species found to be consumed by P. tajacu, the dominant species were: Brosimum alicastrum, Manilkara zapota, Pipper amalago, Zea maiz and an unidentified species. We analyzed nine stomach contents and 16 feces of T. pecari and found that he feeds on 41 species of plants where the main components were fruits too (81.2 % on stomach and 66.8 % on feces). The main species consumed by T. pecari were B. alicastrum, Chamaedorea sp, M. zapota, Mimosa sp, P. amalago and one unidentified species. Despite both peccary species shared 32 species on their diet, their feeding niche was not significant overlapped. Collared peccary and white-lipped peccary are playing a seed predator role for several of the species on which they feed upon. KEY WORDS: Calakmul, diet, coexistence, Tayassuidae, Tayassu pecari and Pecari tajacu