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Relationships between parasites, host physiology, and behaviours are complex. Parasites can influence host hormonal microenvironment and behaviour through "sickness behaviours" that generally conserve energy. Using a parasite removal experiment, we examined the effects of gastrointestinal parasites on fecal glucocorticoid metabolites (fGC) and behaviours of vervet monkeys (Chlorocebus pygerythrus) at Lake Nabugabo, Uganda. We collected parasitological, hormonal, and behavioural data from adult and subadult male and female vervets (N = 19) in 2014 across four study phases: pre-deworming, post-deworming, early reinfection, and late reinfection as well as in 2015. Overall, there was no decrease in fGC after deworming, but there was an increase following natural reinfection. There was no change in feeding across study phases; however, moving, grooming, and resting changed between the post-deworming and late reinfection phases, but not always in the predicted direction. Comparing behaviour across the same months in the following year as in the 2014 experimental study period, we found no differences in moving, feeding, grooming, and resting events. Despite behavioural variation between study phases, we cannot conclude that behavioural changes are due to parasitism rather than other seasonal variation. However, fGC increased following reinfection, which is consistent with parasitism being costly for hosts. more...

Establishing protected areas is a key element of most conservation strategies, but continuous effective management is needed to ensure that biodiversity is protected. Here we provide an evaluation of park effectiveness by quantifying changes in the abundance of the commonly occurring ungulates (bushbuck - Tragelaphus scriptus; red duiker - Cephalophus harveyi; blue duiker - Cephalophus moniticola, bushpigs - Potomochoerus larvatus, and giant forest hogs - Hylochoerus meinertzhageni), and African elephants (forest elephants - Loxodonta cyclotis, savanna elephants - Loxodonta africana, and their hybrids) in Kibale National Park, Uganda and consider the financial commitment needed to ensure protection. Following the upgrading of the protection of Kibale from a forest reserve to a national park, wildlife populations generally increased. Bushpigs are an exception and their populations appear stable. The increases of ungulate and elephant populations typically happened soon after park establishment, with the exception of the giant forest hog that only recently showed an increase. We conducted an assessment of Uganda Wildlife Authorities budget and those of the small NGOs working in the area and considered the contribution that Makerere University Biological Field Stations makes to the community. This analysis indicates that with a small budget UWA and its collaborators have been successful in protecting the park’s ungulate and elephant populations. While the past decades have demonstrated the park’s ability to conserve biodiversity with limited resources, the changing climate and mounting pressures faced by the park will necessitate significantly increased investments. more...

Abstract Central African evergreen broadleaved forests around the equator exhibit a double annual cycle for canopy phenology and carbon uptake seasonality. The underlying drivers of this behavior are poorly understood and the double seasonality is not captured by land surface models (LSM). In this study, we developed a new leaf phenology module into the ORCHIDEE LSM (hereafter ORCHIDEE‐AFP), which utilizes short‐wave incoming radiation (SWd) as the main driver of leaf shedding and partial rejuvenation of the canopy, to simulate the double seasonality of central African forests. The ORCHIDEE‐AFP model has been evaluated by using field data from two forest sites and satellite observations of the enhanced vegetation index (EVI), which is a proxy of young leaf area index (LAIYoung) with leafage less than 6 months, as well as six products of GPP or GPP proxies. Results demonstrate that ORCHIDEE‐AFP successfully reproduces observed leaf turnover (R = 0.45) and young leaf abundance (R = 0.74), and greatly improve the representation of the bimodal leaf phenology. The proportion of grid cells with a significant positive correlation between the seasonality of modeled LAIYoung and observed EVI increased from 0.2% in the standard model to 27% in the new model. For photosynthesis, the proportions of grid cells with significant positive correlations between modeled and observed seasonality range from 26% to 65% across the six GPP evaluation products. The improved performance of the ORCHIDEE‐AFP model in simulating leaf phenology and photosynthesis of central African forests will allow a more accurate assessment of the impacts of climate change in tropical forests. more...

Abstract Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems. more...

Abstract Conservation funding is currently limited; cost‐effective conservation solutions are essential. We suggest that the thousands of field stations worldwide can play key roles at the frontline of biodiversity conservation and have high intrinsic value. We assessed field stations’ conservation return on investment and explored the impact of COVID‐19. We surveyed leaders of field stations across tropical regions that host primate research; 157 field stations in 56 countries responded. Respondents reported improved habitat quality and reduced hunting rates at over 80% of field stations and lower operational costs per km2 than protected areas, yet half of those surveyed have less funding now than in 2019. Spatial analyses support field station presence as reducing deforestation. These “earth observatories” provide a high return on investment; we advocate for increased support of field station programs and for governments to support their vital conservation efforts by investing accordingly. more...

Abstract Efficient foraging plays a critical role in fitness, yet food choices and underlying nutritional goals vary among animals. To understand those choices and therefore the importance of different food resources, many studies estimate food preferences by applying electivity indices that account for resource availabilities. However, the general applicability of electivity indices in biologically relevant foraging scenarios is unclear. Our major aims were to find effective methods to estimate animals' food choices and to investigate long‐term food choices and underlying nutritional goals of the red colobus monkey (Piliocolobus tephrosceles) in Kibale National Park, Uganda, an endangered folivore. We used simulations of different foraging conditions to evaluate the applicability of electivity indices in biologically relevant scenarios to help interpret our results. Then, we used long‐term data collected between 2006 and 2016 on the feeding behavior and ecology of red colobus to determine the consumption frequencies of different foods and their food preferences. Based on these results and nutritional concentrations of young leaves of frequently consumed tree species, we investigated the importance of the protein‐to‐fiber ratio in their diet. Our simulations highlight limitations of electivity indices in biologically relevant foraging scenarios. Further, red colobus clearly chose young leaves over other plant parts, and, considering species and plant part, red colobus fed on many different items, but few dominated their diet. The availability and spatial distribution varied across the most consumed foods, but red colobus preferences remained mostly stable over time. Protein‐to‐fiber ratio had no association with preference but with consumption frequencies of different young leaves. The limitations of electivity indices in different foraging conditions underline the importance of comparing food preferences with consumption frequencies to assess the importance of different food resources. Our results provide a robust understanding of the food choices and nutritional goals of a leaf‐eating animal that can ultimately be used for implementing more effective conservation measures by directing habitat protection or restoration efforts toward these resources. more...

Many of the world’s most biodiverse regions are found in the poorest and second most populous continent of Africa; a continent facing exceptional challenges. Africa is projected to quadruple its population by 2100 and experience increasingly severe climate change and environmental conflict—all of which will ravage biodiversity. Here we assess conservation threats facing Africa and consider how these threats will be affected by human population growth, economic expansion, and climate change. We then evaluate the current capacity and infrastructure available to conserve the continent’s biodiversity. We consider four key questions essential for the future of African conservation: (1) how to build societal support for conservation efforts within Africa; (2) how to build Africa’s education, research, and management capacity; (3) how to finance conservation efforts; and (4) is conservation through development the appropriate approach for Africa? While the challenges are great, ways forward are clear, and we present ideas on how progress can be made. Given Africa’s current modest capacity to address its biodiversity crisis, additional international funding is required, but estimates of the cost of conserving Africa’s biodiversity are within reach. The will to act must build on the sympathy for conservation that is evident in Africa, but this will require building the education capacity within the continent. Considering Africa’s rapidly growing population and the associated huge economic needs, options other than conservation through development need to be more effectively explored. Despite the gravity of the situation, we believe that concerted effort in the coming decades can successfully curb the loss of biodiversity in Africa. more...

In mammal herbivores, fiber digestion usually occurs predominantly in either the foregut or the hindgut. Reports of mechanisms showing synergistic function in both gut regions for the digestion of fiber and other nutrients in wild mammals are rare because it requires integrative study of anatomy, physiology, and gut microbiome. Colobine monkeys (Colobinae) are folivorous, with high-fiber foods fermented primarily in their foreguts. A few colobine species live in temperate regions, so obtaining energy from fiber during the winter is essential. However, the mechanisms enabling this remain largely unknown. We hypothesized that such species possess specialized mechanisms to enhance fiber digestion in the hindgut and studied microbial and morphological digestive adaptations of golden snub-nosed monkeys (GSMs), Rhinopithecus roxellana. which is a temperate forest colobine from central China that experiences high-thermal-energy demands while restricted to a fibrous, low-energy winter diet. We tested for synergistic foregut and hindgut fiber digestion using comparisons of morphology, microbiome composition and function, and digestive efficiency. We found that the GSM colon has a significantly greater volume than that of other foregut-fermenting colobines. The microbiomes of the foregut and hindgut differed significantly in composition and abundance. However, while digestive efficiency and the expression of microbial gene functions for fiber digestion were higher in the foregut than in the hindgut, both gut regions were dominated by microbial taxa producing enzymes to enable active digestion of complex carbohydrates. Our data suggest that both the GSM foregut and hindgut facilitate fiber digestion and that an enlarged colon is likely an adaptation to accommodate high throughput of fiber-rich food during winter. more...