Zambia's Luangwa Research Articles

Long-term data reveal fitness costs of anthropogenic prey depletion for a subordinate competitor, the African wild dog (Lycaon pictus).

Within carnivore guilds, dominant competitors (e.g., lions, Panthera leo) are limited primarily by the density of prey, while subordinate competitors (e.g., African wild dogs, Lycaon pictus) have been limited by the density of dominant competitors. Historically, the fitness and population density of subordinate competitors have not been tightly linked to prey density. However, populations of large herbivores have declined substantially across sub-Saharan Africa due to human impacts, and where prey depletion is severe, fitness costs for competitive subordinates may begin to outweigh the benefits of competitive release. Using long-term intensive monitoring of African wild dogs in Zambia's Luangwa Valley Ecosystem (LVE), we tested the effects of prey depletion on survival and reproduction. We hypothesized that African wild dog fitness would be lower in prey-depleted areas, despite lower lion densities. Our study area included four contiguous regions that varied in protection level, prey density, and lion density. We fit Bayesian Cormack-Jolly-Seber and closed-capture models to estimate effects on survival and population density, and generalized linear models to estimate effects on reproductive success. We found that the LVE is a stronghold for African wild dogs, with an estimated median density of 4.0 individuals/100 km2. Despite this high density, survival and reproduction differed among regions, and both components of fitness were substantially reduced in the region with the lowest prey density. Anthropogenic prey depletion is becoming an important limiting factor for African wild dogs. If prey depletion (or any other form of habitat degradation) becomes severe enough that its fitness costs outweigh the benefits of competitive release, such changes can fundamentally alter the balance between limiting factors for competitively subordinate species.

Advancing protected area effectiveness assessments by disentangling social‐ecological interactions: A case study from the Luangwa Valley, Zambia

AbstractProtected and conserved areas (PCAs) target at biodiversity conservation and human well‐being, but often reflect low levels of effectiveness. Understanding PCAs social‐ecological systems in which people and nature interact in so‐called social‐ecological interactions is key to understanding the roots of (in)effectiveness, and to leverage change toward resilient and sustainable systems. Despite this potential, social‐ecological interactions in PCAs are commonly neglected in effectiveness evaluations. To address this gap, we elaborated a thorough understanding of the social‐ecological interactions in PCAs through the following steps: In a first step, we extracted from scientific literature which social‐ecological interactions influence the effectiveness of PCAs in general and derived influencing factors which shape those interactions. Based on these insights, we developed an analytical framework, which, in a second step, we applied to a case study in North Luangwa, Zambia. We elucidated three dimensions of social‐ecological interactions occurring in the study area: care (e.g., conservation programs), conflict (e.g., disease transmission), and use (e.g., hunting). We visualized relationships between these interactions and associated key variables in a causal loop diagram. Finally, we drew on the case study in Zambia's Luangwa Valley to propose system‐specific metrics for key variables central to the social‐ecological structure of the study area to make effectiveness measurable. Our approach allows for linking site‐specific social‐ecological interactions to PCA effectiveness. More generally, our findings call for the consideration of the relationships between people and nature when assessing conservation effectiveness.

New information on gorgonopsian pedal morphology based on articulated material from Zambia.

Descriptions detailing the postcranial skeleton of gorgonopsians lag far behind those of the group's cranial anatomy. Indeed, most recent phylogenetic recent work has focused exclusively on cranial features, leaving systematic variation in the rest of the skeleton undocumented. Here I describe the articulated pedes of a small gorgonopsian from the upper Permian upper Madumabisa Mudstone Formation of Zambia's Luangwa Basin. Between the two sides, the pedal phalangeal formula can be confidently reconstructed as 2-3-4-5-4, with one disc-like phalanx present in digits three and five, and two discs present in digit four. The lateralmost distal tarsal is confirmed to be a compound element formed by the fusion of distal tarsals four and five, as evidenced by a groove circumscribing the distolateral corner of the element. Nonetheless, a prominent gap was probably present proximal to metatarsal five. A preliminary review of variation in the relative sizes and orientations of the pedal elements shows the possibility that this anatomical unit could contribute phylogenetically useful data. For example, the presence of a disc-like phalanx in digit five likely represents the retention of the primitive phalangeal formula of the pes compared to its absence in a specimen tentatively referred to the derived rubidgeine gorgonopsian Dinogorgon, but this hypothesis requires testing within a broader phylogenetic context.

Do protection gradients explain patterns in herbivore densities? An example with ungulates in Zambia's Luangwa Valley.

Ungulate populations face declines across the globe, and populations are commonly conserved by using protected areas. However, assessing the effectiveness of protected areas in conserving ungulate populations has remained difficult. Using herd size data from four years of line transect surveys and distance sampling models, we modeled population densities of four important herbivore species across a gradient of protection on the edge of Zambia's South Luangwa National Park (SLNP) while accounting for the role of various ecological and anthropogenic variables. Our goal was to test whether protection was responsible for density dynamics in this protection gradient, and whether a hunting moratorium impacted herbivore densities during the studies. For all four species, we estimated lower densities in partially protected buffer areas adjacent to SLNP (ranging from 4.5-fold to 13.2-fold lower) compared to protected parklands. Density trends through the study period were species-specific, with some species increasing, decreasing, or remaining stable in all or some regions of the protection gradient. Surprisingly, when controlling for other covariates, we found that these observed differences were not always detectably related to the level of protection or year. Our findings highlight the importance of accounting for variables beyond strata of interest in evaluating the effectiveness of a protected area. This study highlights the importance of comprehensively modeling ungulate population density across protection gradients, identifies lands within an important protection gradient for targeted conservation and monitoring, documents prey depletion and expands our understanding on the drivers in a critical buffer area in Zambia.

Effect of sustainable poultry interventions on household food security and resilience in game management areas of Zambia's Luangwa Valley: a before-and-after study

Abstract Background Zambia's Luangwa Valley epitomises the linked environmental, agricultural, and human health problems around protected wildlife areas in developing countries. Smallholder crop yields are usually poor, and farmers turn to the unsustainable harvesting of natural resources, including hunting, fishing, and deforestation for charcoal production to supplement household income and food supply. Chronic poverty and food insecurity are pervasive and long-term household and environmental resilience are uncertain. Village poultry can ameliorate these problems, through the provision of animal-source food and income and an alternative to consumption of natural resources. However, the returns on traditional backyard poultry ownership are reduced by high flock losses and poor flock genetics. We, therefore, designed and implemented two poultry interventions and measured their effect on productivity, profitability, and consumption of animal-source food. Methods We implemented two programmes in the Luangwa Valley, Zambia. First, we undertook a community vaccination programme for Newcastle disease virus (NDV) in village chickens in Mambwe and Lundazi districts and gave flock owners instruction in improved management practices through workshops. We recorded changes in flock size over 4 years, using surveys administered every 4 months, and we used other primary and secondary data sources to assess changes in poultry-related income and chicken and egg consumption. For the second programme, we facilitated construction of semi-intensive egg production facilities in 24 communities. Layer-hen facilities each held 40 hens and were owned and operated by a group of 4–5 people. We recorded data on egg productivity (the number of eggs produced on a day divided by the number of hens in the flock on that day), poultry-related income, and egg consumption for 1 year using facility records, a semiannual survey, and qualitative interviews. Findings In areas covered by the NDV vaccine programme, mean household flock size increased from 10·9 birds in July, 2007, to 25·7 birds in November, 2011 (p Interpretation NDV vaccination and improved management sustainably increased flock sizes and improved household income but had no direct effect on household consumption of animal-source food. By contrast, semi-intensive egg production businesses provided both consistent income and significant increases in consumption of animal-source food, not only promoting food security and resilience but also providing a potentially important alternative to bushmeat in villages surrounding ecologically-important protected areas. Funding Atkinson Center for a Sustainable Future (AJT) and the National Institutes of Health (T32 OD011000, SED).

Assessing the sustainability of African lion trophy hunting, with recommendations for policy.

While trophy hunting provides revenue for conservation, it must be carefully managed to avoid negative population impacts, particularly for long-lived species with low natural mortality rates. Trophy hunting has had negative effects on lion populations throughout Africa, and the species serves as an important case study to consider the balance of costs and benefits, and to consider the effectiveness of alternative strategies to conserve exploited species. Age-restricted harvesting is widely recommended to mitigate negative effects of lion hunting, but this recommendation was based on a population model parameterized with data from a well-protected and growing lion population. Here, we used demographic data from lions subject to more typical conditions, including source-sink dynamics between a protected National Park and adjacent hunting areas in Zambia's Luangwa Valley, to develop a stochastic population projection model and evaluate alternative harvest scenarios. Hunting resulted in population declines over a 25-yr period for all continuous harvest strategies, with large declines for quotas >1 lion/concession (~0.5 lion/1,000km2 ) and hunting of males younger than seven years. A strategy that combined periods of recovery, an age limit of ≥7yr, and a maximum quota of ~0.5 lions shot/1,000km2 yielded a risk of extirpation <10%. Our analysis incorporated the effects of human encroachment, poaching, and prey depletion on survival, but assumed that these problems will not increase, which is unlikely. These results suggest conservative management of lion trophy hunting with a combination of regulations. To implement sustainable trophy hunting while maintaining revenue for conservation of hunting areas, our results suggest that hunting fees must increase as a consequence of diminished supply. These findings are broadly applicable to hunted lion populations throughout Africa and to inform global efforts to conserve exploited carnivore populations.

Sustainable smallholder poultry interventions to promote food security and social, agricultural, and ecological resilience in the Luangwa Valley, Zambia.

In Zambia's Luangwa Valley, highly variable rainfall and lack of education, agricultural inputs, and market access constrain agricultural productivity, trapping smallholder farmers in chronic poverty and food insecurity. Human and animal disease (e.g. HIV and Newcastle Disease, respectively), further threaten the resilience of poor families. To cope with various shocks and stressors, many farmers employ short-term coping strategies that threaten ecosystem resilience. Community Markets for Conservation (COMACO) utilizes an agribusiness model to alleviate poverty and food insecurity through conservation farming, market development and value-added food production. COMACO promotes household, agricultural and ecological resilience along two strategic lines: improving recovery from shocks (mitigation) and reducing the risk of shock occurrence. Here we focus on two of COMACO's poultry interventions and present data showing that addressing health and management constraints within the existing village poultry system resulted in significantly improved productivity and profitability. However, once reliable productivity was achieved, farmers preferred to sell chickens rather than eat either the birds or their eggs. Sales of live birds were largely outside the community to avoid price suppression; in contrast, the sale of eggs from community-operated, semi-intensive egg production facilities was invariably within the communities. These facilities resulted in significant increases in both producer income and community consumption of eggs. This intervention therefore has the potential to improve not only producers' economic resilience, but also resilience tied to the food security and physical health of the entire community.

The first karenitid (Therapsida, Therocephalia) from the upper Permian of Gondwana and the biogeography of Permo-Triassic therocephalians

ABSTRACTTherocephalians were an ecologically diverse group of therapsids whose long stratigraphic record and widespread distribution during Permian and Triassic times make them important for understanding biogeographic patterns during a major faunal transition. Here, we describe a new therocephalian, Mupashi migrator gen. et sp. nov., from the upper Madumabisa Mudstone Formation (upper Permian) of Zambia's Luangwa Basin. The specimen has a long snout with a maxilla–vomerine contact on the hard palate, a high antecanine tooth count and numerous postcanines, and a conspicuous boss on the dentary angle whose structure is identical to that of the Russian baurioid Karenites. Additional endocranial anatomy, including palatal and braincase features, are revealed by high-resolution X-ray computed tomography and described in detail in light of the growing availability of tomographic data for therapsids. A phylogenetic analysis of 56 therapsid taxa and 136 cranial and postcranial characters recovers Mupashi as the sister taxon to Karenites, placing the pair between basal ictidosuchid-grade baurioids and the later Triassic bauriamorphs. Parsimony optimizations of geographic occurrences are ambiguous regarding the origination centers of therocephalian subclades. However, the patterns are suggestive of either (1) rapid, early dispersal events of Eutherocephalia and its major subgroups from a Laurasian center during the early–late Permian or, more likely, (2) within-province diversifications with occasional dispersal events occurring between provinces. Regardless, these associations strengthen the hypothesis that unknown but effective dispersal routes to high latitudes were available to therapsids and other tetrapods at least until early–late Permian times.http://zoobank.org/urn:lsid:zoobank.org:pub:B1E95B00-85BC-45E3-A823-841AD701A3F3SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Huttenlocker, A. K., and C. A. Sidor. 2016. The first karenitid (Therapsida, Therocephalia) from the upper Permian of Gondwana and the biogeography of Permo-Triassic therocephalians. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1111897.

Studies of trypanosomiasis in the Luangwa valley, north-eastern Zambia

BackgroundThe present study, conducted in Zambia’s Luangwa valley where both animal African trypanosomiasis (AAT) and human African trypanosomiasis (HAT) are endemic, combined the use of microscopy and molecular techniques to determine the presence of trypanosome species in cattle, goats and tsetse flies.MethodsThis study was conducted between 2008 and 2010 in Petauke, Chama and Isoka districts, north-eastern Zambia. A total of 243 cattle, 36 goats and 546 tsetse flies, were examined for presence of trypanosome species using microscopy, PCR and loop-mediated isothermal amplification (LAMP).ResultsThere was poor agreement among the test methods used for detection of trypanosomes species in animal blood and tsetse flies. Trypanosomes were observed in 6.1 % (95 % CI: 3.3-8.9 %) of the animals sampled by microscopy, 7.5 % (95 % CI: 4.4–10.6 %) by PCR and 18.6 % (95 % CI: 13.6–23.6 %) by PFR-LAMP. PFR-LAMP was more sensitive for detecting Trypanozoon than KIN-PCR. The highest occurrence of AAT was recorded in cattle from Petauke (58.7 %, 95 % CI: 44.7–72.7 %) while the lowest was from Isoka (5.4 %, 95 % CI: 0.8–10.0 %). Infection of both cattle and goats with Trypanosoma congolense and T. vivax was associated with clinical AAT.ConclusionWhen selecting molecular techniques for AAT surveillance in endemic regions, the KIN-PCR and species-specific PCR may be recommended for screening animal or tsetse fly samples for T. congolense and T. vivax, respectively. On the other hand, species-specific PCR and/or LAMP might be of greater value in the screening of animal and human body fluids as well as tsetse fly samples for Trypanozoon.

Preliminary Investigation of Trypanosomosis in Exotic Dog Breeds from Zambia's Luangwa and Zambezi Valleys Using LAMP

Abstract. Canine African trypanosomosis (CAT) is rarely reported in the literature. In this preliminary study, we evaluated the performance of loop-mediated isothermal amplification (LAMP) against microscopy to detect CAT in six exotic dog breeds naturally infected with trypanosomes from Zambia's South Luangwa National Park and Chiawa Game Management Area. To our knowledge, this is the first report of CAT in Zambia. The patients exhibited a variety of aspecific clinical signs. The LAMP did not only confirm all six parasitologically positive CAT cases detected passively between April 2010 and January 2012, but was also critical in trypanosome speciation. According to LAMP, the majority of the dogs had monolytic infections with either Trypanosoma congolense or Trypanosoma brucei rhodesiense. The LAMP is thus a potential simple and cost-effective tool for trypanosome diagnosis in endemic regions. The rare report of zoonotic trypanosomes in dogs in Zambia has public health implications and justifies further investigations of CAT.

Malaria Infection and Anemia Prevalence in Zambia's Luangwa District: An Area of Near-Universal Insecticide-Treated Mosquito Net Coverage

We examined the relationship between insecticide-treated mosquito nets (ITNs), malaria parasite infection, and severe anemia prevalence in children in Luangwa District, Zambia, an area with near-universal ITN coverage, at the end of the 2008 and 2010 malaria transmission seasons. Malaria parasite infection prevalence among children < 5 years old was 9.7% (95% confidence interval [CI] = 8.0–11.4%) over both survey years. Prevalence of severe anemia among children 6–59 months old was 6.9% (95% CI = 5.4–8.5%) over both survey years. Within this context of near-universal ITN coverage, we were unable to detect a significant association between malaria parasite or severe anemia prevalence and ITNs (possession and use). In addition to maintaining universal ITN coverage, it will be essential for the malaria control program to achieve high ITN use and laboratory diagnosis and treatment of all fevers among all age groups to further reduce the malaria burden in this area.