Theses and Dissertations at Montana State University (MSU)
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733
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Item Effects of de-snaring on the demography and population dynamics of African lions(Montana State University - Bozeman, College of Letters & Science, 2023) Banda, Kambwiri; Chairperson, Graduate Committee: Scott CreelLions and other African large carnivores are in decline, due in part to effects of illegal hunting with snares, which can reduce prey availability and directly kill or injure carnivores. It is difficult to effectively remove snares from large ecosystems by patrolling, but an additional approach to reduce effects on large carnivores is to monitor the population closely and de-snare individuals who are found in a snare or have broken free but still carry the wire (often with serious injury). The effectiveness of de-snaring programs to reduce impacts on large carnivores has not been directly tested. Here, we used long-term demographic data from 386 individually identified lions in the Luangwa Valley Ecosystem to test the effects on population growth (lambda) and population size (N) of a program to remove snares from injured lions and treat their wounds. Stochastic Leslie matrix projections for a period of five years showed that the population grew with the benefits of de-snaring but was expected to decline without de-snaring. Mean annual growth (lambda) was 1.037 (growth in 70% of years), closely matching observed changes in population size. Mean annual growth was 0.99 (with growth in 47% of years) for a model that assumed snared animals would have died if not treated, and 0.95 (with growth in 37% of years) for models that also accounted for super-additive effects via the death of dependent cubs and increased infanticide with increased male mortality. De-snaring requires intensive effort, but it can appreciably reduce the effect of snaring on lion population dynamics.Item Testing the effects of anthropogenic pressures on African lions and their prey in the Greater Kafue Ecosystem, Zambia(Montana State University - Bozeman, College of Letters & Science, 2020) Vinks, Milan Alexander; Chairperson, Graduate Committee: Scott Creel; Scott Creel, Paul Schuette, Wigganson Matandiko, Elias Rosenblatt, Carolyn Sanguinetti, Kambwiri Banda, Ben Goodheart, Matthew S. Becker, Clive Chifunte, and Chuma Simukonda were co-authors of the article, 'Testing the effects of anthropogenic pressures on a diverse African herbivore community' in the journal 'Ecosphere' which is contained within this thesis.; Scott Creel, Paul Schuette, Matthew S. Becker, Elias Rosenblatt, Carolyn Sanguinetti, Kambwiri Banda, Ben Goodheart, Kim Young-Overton, Xia Stevens, Clive Chifunte, Neil Midlane, and Chuma Simukonda were co-authors of the article, 'Response of lion demography and dynamics to the loss of prey and changes in prey community composition' submitted to the journal 'Ecological Applications' which is contained within this thesis.Rapid human population growth across Africa has put tremendous pressure on large herbivore and large carnivore populations, and most of these large terrestrial species are now limited to residing within or adjacent to protected area (PA) networks. However, high rates of human encroachment and associated activities around and within PAs are jeopardizing their effectiveness and have become a major conservation concern. High rates of illegal harvest are linked to human encroachment and can have devastating effects on large herbivore and large carnivore populations. Large herbivore declines are often greatest in areas with high rates of illegal offtake and ensuing prey depletion can be a primary driver of large carnivore declines. Kafue National Park (KNP) of central Zambia supports a diverse large herbivore community and the country's second largest lion population. However, KNP is thought to be experiencing human-caused wildlife declines, providing a unique opportunity to evaluate anthropogenic effects on both the large herbivores and large carnivores of this system. Here, we evaluated the status and major anthropogenic and environmental drivers of KNP's large herbivore populations and lion population. First, we estimated population densities and distribution of the ten most abundant large herbivore species using stratified ground-based surveys conducted from 2012 - 2018. These data indicated that population densities were consistently low across species and areas, though there was ecologically important variation among species and size classes. Moreover, densities of larger-bodied herbivores were greatly depressed relative to smaller species. Second, we evaluated population density, survival rates, and demography for the KNP lion population from 2013 - 2018. These data indicated that age- and sex-specific survival rates for settled individuals were generally high, and factors known to correlate with local prey density had small effects on lion survival. In contrast, average lion density was low and recruitment of cubs was poor. These findings suggest that low recruitment might be a better signal of low prey density than survival. Overall, large herbivores and lions appear to be limited by human activities in KNP. Increased resource protection and reducing the underlying drivers of prey depletion are urgent conservation needs to facilitate the recovery of these economically and ecologically valuable species.Item Assessing the impacts of protection gradients on large African carnivore density and survival : an example with African lion and leopard in the Luangwa Valley, Zambia(Montana State University - Bozeman, College of Letters & Science, 2016) Rosenblatt, Elias Goldsmith; Chairperson, Graduate Committee: Scott Creel; Matthew S. Becker, Scott Creel, Egil Droge, Thandiwe Mweetwa, Paul A.Schuette, Fred Watson, Johnathan Merkle and Henry Mwape were co-authors of the article, 'Detecting declines of apex carnivores and evaluating their causes: an example with Zambian lions' in the journal 'Biological conservation' which is contained within this thesis.; Scott Creel, Matthew S. Becker, Johnathan Merkle, Henry Mwape, Paul Schuette, Twakundine Simpamba were co-authors of the article, 'Effects of a protection gradient on carnivore density and survival: an example with leopards in the Luangwa Valley, Zambia' in the journal 'Ecology and evolution' which is contained within this thesis.; Elias Rosenblatt was a co-author of the article, 'Using pedigree reconstruction to estimate population size: genotypes are more than individually unique marks' in the journal 'Ecology and evolution' which is contained within this thesis.Large carnivores are in rapid global decline, primarily due to anthropogenic pressures. Human activities on the periphery of protected areas can limit carnivore populations, but measurements of the strength of such effects are limited. Both African lion (Panthera leo) and leopard (Panthera pardus) are declining throughout their ranges, and thus accurate monitoring of key populations is critical. Both of these species face pressure from encroaching human populations, particularly from trophy hunting, illegal bushmeat harvest, and human-carnivore conflict. In Zambia, South Luangwa National Park and its buffer areas are thought to contain the country's largest lion and leopard populations. However, this protection gradient is experiencing rapid human population growth and activities that are known to threaten large carnivore populations elsewhere. Here we examined the status and major anthropogenic drivers of the South Luangwa lion and leopard populations. First, we estimated population size, trends, survival rates and demography for the South Luangwa lion population from 2008 to 2012. These data indicated that trophy hunting was impacting the South Luangwa lion population, and potential management actions exist and should be implemented to mitigate impacts from trophy hunting. Second, we measured how the density and survival rates of South Luangwa's leopard population varied across this gradient of protection using remote camera trap surveys from 2012-2014 during a ban on trophy hunting. We estimated that leopard density was higher inside South Luangwa National Park as compared to an adjacent buffer area with lower levels of protection, but could not detect differences in leopard survival across these two areas. This difference in density was most likely driven by prey depletion in the buffer areas, and this limitation is likely an issue for other sympatric large carnivore species. Finally, we developed a rapid survey method based on pedigree reconstruction to estimate population size, with validation based on a simulated population. This method shows promise for surveying unstudied large carnivore populations. Overall, large carnivore populations face growing anthropogenic pressures worldwide, and management action to mitigate population declines must be informed by intensive monitoring of key large carnivore populations to identify the drivers and dynamics of such declines.