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Proclaimed in 1907, Etosha National Park in northern Namibia is an iconic dryland system with a rich history of wildlife conservation and research. A recent research symposium on wildlife conservation in the Greater Etosha Landscape (GEL) highlighted increased concern of how intensification of global change will affect wildlife conservation based on participant responses to a questionnaire. The GEL includes Etosha and surrounding areas, the latter divided by a veterinary fence into large, private farms to the south and communal areas of residential and farming land to the north. Here, we leverage our knowledge of this ecosystem to provide insight into the broader challenges facing wildlife conservation in this vulnerable dryland environment. We first look backward, summarizing the history of wildlife conservation and research trends in the GEL based on a literature review, providing a broad-scale understanding of the socioecological processes that drive dryland system dynamics. We then look forward, focusing on eight key areas of challenge and opportunity for this ecosystem: climate change, water availability and quality, vegetation and fire management, adaptability of wildlife populations, disease risk, human-wildlife conflict, wildlife crime, and human dimensions of wildlife conservation. Using this model system, we summarize key lessons and identify critical threats highlighting future research needs to support wildlife management. Research in the GEL has followed a trajectory seen elsewhere reflecting an increase in complexity and integration across biological scales over time. Yet, despite these trends, a gap exists between the scope of recent research efforts and the needs of wildlife conservation to adapt to climate and land-use changes. Given the complex nature of climate change, in addition to locally existing system stressors, a framework of forward-thinking adaptive management to address these challenges, supported by integrative and multidisciplinary research could be beneficial. One critical area for growth is to better integrate research and wildlife management across land-use types. Such efforts have the potential to support wildlife conservation efforts and human development goals, while building resilience against the impacts of climate change. While our conclusions reflect the specifics of the GEL ecosystem, they have direct relevance for other African dryland systems impacted by global change. Publisher PDF

Investigations into natural resource use and access are often limited to rural areas; such use is not considered an integral part of urban livelihood strategies, especially amongst the poor. With growing urban food insecurity, poverty, and unequal access to services, natural resource use may provide a viable alternative to cash-based resources, thus, allowing households to navigate the rural–urban continuum as they address livelihood needs. This may be especially pertinent for growing, but small, urban landscapes that are in transition. We investigated the use of and access to natural resources in households in rural (Lesoma), peri-urban (Kazungula), and urban (Kasane) settlements in northern Botswana. Semi-structured questionnaires for 85 households were used to investigate household demographics, variety of natural resources used, the availability, use, and importance of natural resources, threats to resources, harvesting locations, and extent of resource commercialization. Significant differences were identified in the mean number of resources used by households across the three settlements (Kruskal–Wallis Chi-squared = 9.29, df = 2, p = 0.01). Using the post hoc test Conover with Bonferroni adjustment, mean natural resource use between the urban and peri-urban villages did not differ significantly (p = 1). However, both types of villages differed from the rural village in mean resource use (urban p = 0.007 and peri-urban p = 0.012). Nevertheless, urban and peri-urban households reported use of a broad range of natural resources, highlighting the importance of these products in transitioning landscapes. Across the study villages, natural resource harvesting occurred predominantly on communal land. Primary barriers to resource access were perceived to be strict government regulations and decreasing resource availability. Natural resource commercialization was identified as a potential opportunity but was often carried out only on a small scale. The use of natural resources is intuitively thought to be associated with rural areas, but our results suggest that such resources form an important part of livelihoods across urban and peri-urban landscapes as well. This continued reliance on natural resources raises important planning questions about how to ensure both the ongoing conservation of forested and other natural areas, and the availability of associated resources for urban livelihoods. In this regard, small urban towns that are rapidly transitioning from rural landscapes provide a targeted opportunity for early intervention. Our findings underpin the vital role that natural areas play in supporting the livelihoods of the urban poor and highlight the need to encourage land designation and management of such areas not only for conservation but also as a safety net for vulnerable urban households.

In regions rich in natural resources, nature-based tourism is advancing rapidly. This form of development is identified as an important economic opportunity for local communities but can impact ecosystem services through rapid landscape transformation, threatening the livelihoods of the most impoverished sectors of a community. While it is accepted that communities should participate in the planning process, variation in community and household-level landscape dependencies and priorities can create a fractured viewpoint that is difficult to integrate into the land planning process. Power structures and special interests can subvert participatory processes and input at the community level. In the Chobe District, Northern Botswana, tourism, and other related developments had occurred at a rapid pace around the Chobe National Park creating access barriers, in some instances, to essential natural resource areas. We evaluate community landscape dependencies and participatory approaches to the development of inclusive land use maps. Spatial information on land use dependencies from household surveys were used to form the bases of reiterative village-level participatory mapping exercises (n = 179 households, six villages). The activities were conducted through traditional leadership structures. Landscape dependencies were widespread across study villages in both natural resource and agricultural sectors. Cluster and CART analysis of household data identified important variation in landscape dependencies between and within study villages. Fishing was the most important factor predicting gender of headship with male-headed households using this resource more frequently. Spatial data from these household consultations were used to create a draft map that was reiteratively refined through participatory map building exercises until final approval was provided by community members and their traditional leaders in a village. Scaled consultations and involvement of the traditional leadership limited the ability of power structures to control the process and/or subvert the interests of more vulnerable members of a community. Mapping outputs were later successfully used in land planning exercises and consultations. Development of inclusive community consensus on landscape dependencies should be undertaken before lucrative tourism ventures and land allocations are advanced in competition to the needs of more vulnerable and often voiceless sectors of a community.

While there is agreement that ecosystem services provide critical life support, local communities can be disengaged from the process of conservation, allocation and decision-making. How do we move from concepts, which are often seen as hand waving by natural resource users and policymakers, to concrete valuation appreciated at the level of the household, community and policy maker? In this special issue, we explore examples from southern Africa where ecosystem services are engaged and identified by users as important and critical to improved livelihoods as well as advancing business outcomes. Two papers focus on how small, disenfranchised communities can be empowered to build a common vision of natural resource priority and identify a voice in the planning process. The second two papers in this issue investigate the role of two functional mammal guilds, bats and mesocarnivores, in reducing crop depredation. The final paper investigates how ecovolunteerism can fulfill conservation and community development gaps that occur when governments and NGO’s do not avail themselves to local communities. Together these research papers provide a holistic and synthetic view about the links between humans and ecosystems, help to assess community level capacity for sustainability and stewardship, and define what the metrics of success look like.

Diarrheal disease is the second largest cause of mortality in children younger than 5, yet our ability to anticipate and prepare for outbreaks remains limited. Here, we develop and test an epidemiological forecast model for childhood diarrheal disease in Chobe District, Botswana. Our prediction system uses a compartmental susceptible-infected-recovered-susceptible (SIRS) model coupled with Bayesian data assimilation to infer relevant epidemiological parameter values and generate retrospective forecasts. Our model inferred two system parameters and accurately simulated weekly observed diarrhea cases from 2007-2017. Accurate retrospective forecasts for diarrhea outbreaks were generated up to six weeks before the predicted peak of the outbreak, and accuracy increased over the progression of the outbreak. Many forecasts generated by our model system were more accurate than predictions made using only historical data trends. Accurate real-time forecasts have the potential to increase local preparedness for coming outbreaks through improved resource allocation and healthcare worker distribution. National Science Foundation Dynamics of Coupled Natural and Human Systems [1518486]; National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA [T32 ES023770] This project was made possible by a grant from the National Science Foundation Dynamics of Coupled Natural and Human Systems (Award #1518486, KAA) and by a training grant from National Institutes of Health (T32 ES023770). We would also like to thank the Botswana Ministry of Health, the Chobe District Health Team, Dr. M. Vandewalle, R. Sut-cliffe, L. Nkwalale, M. Heneghan, K. Ramsden, T. Motseothata, S. Vandewalle, C. A. Nichols, and others who contributed importantly to the collection of the health data used in this study.

Technological improvements in battery life and physical dimensions of Global Positioning System (GPS) telemetry have increased the number of locations one can collect, but due to relatively unimproved GPS accuracy this also increases the number of locations with unacceptable measurement error. We propose and show an example of a new method for screening data for locations with unacceptable error. We also propose a new screening metric: estimated elevation error (EEE). EEE identifies unacceptable xy -coordinate error in some cases better than do methods that use horizontal dilution of precision (HDOP) or fix dimension (2-D or 3-D). Our screening method combines test data and a model-averaging information-theoretic framework that uses a priori candidate models of telemetry measurement error. We demonstrate this method using experimental data collected on banded mongooses ( Mungos mungo ). One can adapt this screening method to any GPS data.

Free-ranging banded mongooses are infected by the novel pathogen, Mycobacterium mungi in northern Botswana. A reliable method for determining stress-related physiological responses in banded mongooses will increase our understanding of the stress response in M. mungi infection. Therefore, our aim was to examine the suitability of four enzyme immunoassays (EIAs) for monitoring adrenocortical endocrine function in captive and free-ranging banded mongooses based on fecal glucocorticoid metabolite (FGM) analysis. A conducted adrenocorticotropic hormone challenge revealed suitability of a valid measurement of FGM levels in banded mongoose feces for all four tested EIAs, with an 11-oxoetiocholanolone assay detecting 11,17-dioxoandrostanes (11,17-DOA) performing best. Subsequent analyses using only this EIA showed the expected decrease in FGM concentrations 48 h after administering dexamethasone sodium phosphate. Furthermore, captive mongooses showed higher FGM concentrations during reproductive activity, agonistic encounters and depredation events. Finally, a late-stage, tuberculosis-infected moribund mongoose in a free-ranging troop had a 54-fold elevation in FGM levels relative to the rest of the troop. Measurements of gastrointestinal transit times and FGM metabolism post-defecation indicate that the time delay of FGM excretion approximately corresponded with food transit time and that FGM metabolism is minimal up to 8h post-defecation. The ability to reliably assess adrenocortical endocrine function in banded mongoose now provides a solid basis for advancing our understanding of infectious disease and endocrinology in this species.

Using two in vivo methods, microdialysis and rapid in situ electrochemistry, this study examined the modulation of extracellular glutamate levels by endogenously produced kynurenic acid (KYNA) in the prefrontal cortex (PFC) of awake rats. Measured by microdialysis, intraperitoneal (i.p.) administration of KYNA's bioprecursor L-kynurenine dose-dependently elevated extracellular KYNA and reduced extracellular glutamate (nadir after 50 mg/kg kynurenine: 60% decrease from baseline values). This dose-dependent decrease in glutamate levels was also seen using a glutamate-sensitive microelectrode array (MEA) (31% decrease following 50 mg/kg kynurenine). The kynurenine-induced reduction in glutamate was blocked (microdialysis) or attenuated (MEA) by co-administration of galantamine (3 mg/kg, i.p.), a drug that competes with KYNA at an allosteric potentiating site of the α7 nicotinic acetylcholine receptor. In separate experiments, extracellular glutamate levels were measured by MEA following the local perfusion (45 min) of the PFC with kynurenine (2.5 μM) or the selective KYNA biosynthesis inhibitor S-ethylsulfonylbenzoylalanine (S-ESBA; 5 mM). In agreement with previous microdialysis studies, systemic kynurenine application produced a reversible reduction in glutamate (nadir: −29%), whereas perfusion with S-ESBA increased glutamate levels reversibly (maximum: +38%). Collectively, these results demonstrate that fluctuations in the biosynthesis of KYNA in the PFC bi-directionally modulate extracellular glutamate levels, and that qualitatively very similar data are obtained by microdialysis and MEA. Since KYNA levels are elevated in the PFC of individuals with schizophrenia, and since prefrontal glutamatergic and nicotinic transmission mediate cognitive flexibility, normalization of KYNA levels in the PFC may constitute an effective treatment strategy for alleviating cognitive deficits in schizophrenia.

A retrospective serosurvey of multi-host feline and canine viruses among carnivore species in southern Africa ( n = 1018) identified widespread pathogen exposure even in remote protected areas. In contrast to mortality experienced in East African predators, canine distemper virus (CDV) infection among African wild dogs ( Lycaon pictus ) in Botswana was not associated with identifiable change in pup survivorship or disease related mortality of adults. A disease outbreak of unknown aetiology occurred in the same population over 4 weeks in 1996. Outbreak boundaries coincided with ecotones, not the spatial distribution of contiguous packs, highlighting the potential importance of landscape heterogeneities in these processes. Direct management of pathogens in domestic animal reservoirs is complicated by the apparent complexity of pathogen maintenance and transmission in these large systems. Conservation effort should be focused at securing large metapopulations able to compensate for expected episodic generalist pathogen invasion and attention directed to addressing underlying causes of population depression such as habitat loss and wildlife conflict.

Feline immunodeficiency virus (FIV) causes AIDS in the domestic cat (Felis catus) but has not been explicitly associated with AIDS pathology in any of the eight free-ranging species of Felidae that are endemic with circulating FIV strains. African lion (Panthera leo) populations are infected with lion-specific FIV strains (FIVple), yet there remains uncertainty about the degree to which FIV infection impacts their health. Reported CD4+ T-lymphocyte depletion in FIVple-infected lions and anecdotal reports of lion morbidity associated with FIV seroprevalence emphasize the concern as to whether FIVple is innocuous or pathogenic. Here we monitored clinical, biochemical, histological and serological parameters among FIVple-positive (N=47) as compared to FIVple-negative (N=17) lions anesthetized and sampled on multiple occasions between 1999 and 2006 in Botswana. Relative to uninfected lions, FIVple-infected lions displayed a significant elevation in the prevalence of AIDS-defining conditions: lymphadenopathy, gingivitis, tongue papillomas, dehydration, and poor coat condition, as well as displaying abnormal red blood cell parameters, depressed serum albumin, and elevated liver enzymes and gamma globulin. Spleen and lymph node biopsies from free-ranging FIVple-infected lions (N=9) revealed evidence of lymphoid depletion, the hallmark pathology documented in immunodeficiency virus infections of humans (HIV-1), macaques, and domestic cats. We conclude that over time FIVple infections in free-ranging lions can lead to adverse clinical, immunological, and pathological outcomes in some individuals that parallel sequelae caused by lentivirus infection in humans (HIV), Asian macaques (SIV) and domestic cats (FIVfca).

African horse sickness (AHS) is a disease that affects equids, and is principally transmitted by Culicoides spp. that are biological vectors of AHS viruses (AHSV). The repeated spread of AHSV from sub-Saharan Africa to the Middle East, northern Africa and the Iberian peninsula indicate that a better understanding of AHS epizootiology is needed. African horse sickness has long been known to infect and cause mortality among domestic dogs that ingest virus contaminated meat, but it is uncertain what role carnivores play in transmission of the virus. We present evidence of widespread natural AHS infection among a diversity of African carnivore species. We hypothesize that such infection resulted from ingestion of meat and organs from AHS-infected prey species. The effect of AHS on the carnivores is unknown, as is their role in the maintenance cycle of the disease.

A quantitative assay for fibrin or other insoluble fibrin-like antigens ("fibrin") in small samples of intima is described. Tissue samples were subjected to electrophoresis directly from the intima into an antibody-containing gel to remove and measure fibrinogen and other soluble fibrin reactive antigens (FRA). The residual tissue was then exhaustively incubated with plasmin, and the soluble fragments generated from the insoluble "fibrin" were measured by quantitative immunoelectrophoresis. "Fibrin" accounted for about 2% of the tissue dry weight in normal intima and the ratio fibrinogen/"fibrin" was 1-1.5. In the gelatinous lesions, which seem to be the precursors of fibrous plaques, there was a small increase in "fibrin" but a substantial increase in fibrinogen and low density (LD)-lipoprotein, and the ratio fibrinogen/"fibrin" rose to about 3, which suggests that the increase in "fibrin" is secondary to increased permeation of fibrinogen. At the edges of large plaques there was also a threefold increase in fibrinogen, but "fibrin" increased fivefold, and accounted for 10% of the tissue dry weight. The same high concentration was found in the centres of large fibrous plaques with advanced atheroma lipid. Raised levels of "fibrin" were accompanied by raised levels of fibrinogen in most tissue samples. About 80% of the total soluble FRA could be clotted with thrombin; there was no significant difference between normal intima and lesions, and the proportion clotted was not related to "fibrin" content.