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Snowy Plover Demography in OregonGaines, Eleanor Prindiville 03 June 2019 (has links)
A thorough understanding of demographic parameters and their contribution to overall population growth is fundamental to effective conservation of small populations, but this information is often lacking. The Pacific Coast population of the Western Snowy Plover (Charadrius nivosus nivosus) is listed as threatened and has been the target of long-term, multi-pronged management in Oregon. The Oregon coastal population has been intensively monitored since 1990, and over 80% of the population is color banded, but a comprehensive analysis of demographic parameters and the effect of management on vital rates and population growth has been unavailable until now. Here, the author used capture-mark-resight techniques to document survival at each life stage and to explore environmental and management factors that best explained variation in survival over a 25-year study period. The author analyzed the effects of habitat restoration, exclosure use, and lethal predator management on survival at appropriate life stages and evaluated the effects of one management option, lethal predator control, on overall population growth. Chick survival to fledging improved dramatically after the chicks' 5th day, was higher in years with lethal predator management, and was highest during the peak of the long brood-rearing season. Cold weather, particularly during the chicks' first 5 days, had a negative effect on survival to fledging. Juvenile survival from fledging to the following spring declined over the study period, but rebounded after implementation of lethal predator management. Adult survival was lower in wetter-than-average winters and higher in years with predator management. The author used the survival analyses and productivity data collected over 25 years in a matrix population model to reveal that population growth is most sensitive to changes in adult survival, and that while predator management is important for continued growth, its use may be scaled back by as much as 50% and still maintain a growing population. My results, encompassing all phases of this species' life cycle, demonstrate that with holistic and thoughtful adaptive management, and with the cooperation of numerous agencies, a balance can be struck between protection and control of native species to bring about recovery of species threatened with (local) extinction.
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Patterns and economic impacts of livestock predation in rural communities bordering Makgadikgadi Pans National Park in Botswana.Dikobe, Leonard Mogopodi. January 1997 (has links)
Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more cattle than those who own few. Gweta contrasts with Khumaga, having livestock predation highest during dry seasons, less reduction in livestock sales and a lower value of pending compensation claims. These predation patterns synchronise with movements of zebra and wildebeest to and from the Boteti river. Losses of livestock affect the utility derived from livestock and monetary gains from direct sales. Costs due to loss of biodiversity, though not quantified, add to those borne by the State through predator control. Both the State and the farmers loose. These losses reduce the incentives of the latter to conserve species that contribute reduction in their returns. The issue of State expenditure on predator control illustrates the possible need for re-direction of such funds into farmer-based predator control, much as an integral part of the current southern African trend of community-based natural resource management. Key words: livestock predation, predator control, economics, conservation, Botswana. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1997.
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Options for eland: a multi-scale assessment of antipredatory responses of a vulnerable prey species to their dominant predator in the Eastern Cape, South AfricaLeaver, Jessica January 2014 (has links)
Eland Tragelaphus oryx are the largest and slowest African antelope, falling within the preferred weight range of the prey of lions Panthera leo. Little is known, however, about the antipredatory strategies employed by eland. Rapid population declines in several small reserves following the reintroduction of lions suggest that the antipredatory strategies of eland may be compromised in spatially limited areas. This emphasises the need for research aimed at investigating how eland respond to lions, particularly in the spatial context, given that lions are increasingly being reintroduced into small reserves in South Africa. This study aimed to investigate lion-eland interactions at multiple scales and determine where on the landscape eland were vulnerable to predation. Adult female eland (n = 3 per site) in breeding herds were collared with GPS satellite collars in two study sites; the Nyathi section of Addo Elephant National Park (Nyathi) and Mountain Zebra National Park (MZNP) in the Eastern Cape, South Africa. A reintroduced population of lions, comprising two males and one female, was present in each study site, with individuals fitted with GPS satellite collars. At a broad spatiotemporal scale, eland did not avoid lions and there was considerable overlap between eland and lion home ranges in both study sites. At a finer spatiotemporal scale however, eland and lion space use was asynchronous in time, except in the case of the female lion in Nyathi where there was considerable overlap at the finest temporal scale investigated (i.e. monthly). Herd-associated eland in Nyathi were killed most frequently in areas associated with high long-term use by the female lion, showing that failure to avoid the female lion at a fine scale increased predation risk for eland. Secondly, eland in Nyathi were killed most frequently in habitat types of intermediate structural density (i.e. mixed habitats), which limited the viewshed of eland but presumably offered increased forage. This habitat type was selected for by eland, despite it being associated with a higher level of predation risk. This suggested that eland in Nyathi traded off safety for forage. In MZNP, predation of herd-associated eland was low which reflected the limited spatial overlap between eland and lion at a fine scale in this reserve. In Nyathi, but not in MZNP, eland responded to lions within 1.5 km by increasing their movement rate, with this response particularly strong at night. The findings of this study show that eland responses to lions are scale-dependent and site-specific. Furthermore, eland responses to lions were shown to be lion gender-specific. This study has increased our understanding of the antipredatory behaviours of eland and demonstrated the importance of investigating prey responses to predation risk at multiple scales.
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Optimal policies directed at reducing pest damages for a pestpredator model /Chan, Wenyaw January 1984 (has links)
No description available.
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An assessment of human carnivore conflict in the Kalahari region of BotswanaKlein, Rebecca Ann January 2014 (has links)
Human wildlife conflict is a considerable conservation challenge that threatens many carnivore species worldwide and is a result of complex socio-economic and ecological processes. An understanding of the drivers of conflict is essential for any efforts to achieve coexistence. This study investigated the levels of conflict, livestock management and tolerance amongst the farming communities of the Southern and Western Kalahari in Botswana. A questionnaire survey was completed with 310 farmers throughout the region. The majority of respondents regarded coexisting with carnivores as a challenge, with losses due to depredation perceived as the greatest problem facing farmers. Conflict was widespread throughout the study area, with some spatial variations for certain species. Cattle management levels were low and while smallstock management was better, the use of improved levels of management could reduce current levels of conflict. Tolerance levels were generally low with few respondents seeing the benefits of coexistence with carnivore species. The results indicated that farm type, gender, education level, source of income, livestock numbers, location and land use all have an effect on perceived conflict and tolerance levels and strongly interact with each other. In general cattleposts were characterised by higher proportions of females, lower education levels, more benefits derived from wildlife and veld products and fewer livestock than fenced ranches. They also experienced more conflict, carried out more management and had better tolerance levels. It could be that closer connections to the land and deriving benefits from natural resources resulted in more tolerance and this is certainly worth further investigation. An improvement in the use of effective methods of livestock management, targeted environmental education programs to develop a greater awareness for the conservation value of carnivores and a diversification of livelihoods to include benefits from natural resources have the potential to reduce conflict and improve tolerance in the Kalahari region.
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A systems-thinking based evaluation of predator conflict management on selected South African farms.Snow, Timothy V. January 2008 (has links)
The backbone of this study was a systems thinking based analysis of the management and control of predators as practiced in South Africa since the advent of Europeans in 1652. The first bounties were introduced for a variety of animal species in 1656. Many species became labeled as vermin and were persecuted, often with the intention of eradication. A variety of controls have been applied, of which many have not kept pace with contemporary thinking or technology, and which by simply killing predators fail to address the crux of the issue of predator – livestock conflict. Many of the methods used cannot be applied to specifically remove an individual damage-causing animal. Considerable collateral ecological damage is inflicted by the killing of animals regarded as innocent bystanders. The objective of the analysis was to highlight the futility of temporary solutions which fail to resolve the conflict in the long term. These quick fixes frequently perpetuate an ecological imbalance which exacerbates the predator – livestock conflict. The analysis used raw data from a questionnaire survey conducted by the Poison Working Group of the Endangered Wildlife Trust (EWT-PWG) (2003). The EWT-PWG intended to assess pesticide abuse as toxicant for predators by farmers, and to identify all control methods used. The data forthcoming was Cartesian in nature and a fixed snap-shot in time. This study sought to identify the root cause of the conflict by applying systems thinking which added the dimension of cause and effect interrogation. The study categorised and described predator conflict management methods as lethal or preventative, and assessed each category in archetypal terms from a systems thinking perspective. It also sought to identify leverage points, or small changes which have profound effects, to stimulate a change in approach to humanpredator conflict management. In order to assess and illustrate the positive change brought about by application of preventative methods, a small group of farmers who had initiated changes in their predator conflict management over the five years subsequent to the EWTPWG survey were selected from the original group for reassessment. Through evaluation of predator conflict management methods from a systems thinking perspective, and by probing learning processes, the shortcomings or failure of inappropriate management responses to conflict situations were shown to exacerbate conflicts. Contrarily, it was illustrated that application of systems thinking and a process of addressing the root cause of conflict issues in predator conflict management, was a longer term solution. The study illustrated that application of long term proactive prevention and conflict avoidance principles, can offer long term solutions for predator conflict managers. / Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2008.
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The roles of black-backed jackals and caracals in issues of human-wildlife conflict in the Eastern Cape, South Africa / The perceived effectiveness of mesopredator control techniques and the mammalian diet of black-backed jackals in the Eastern Cape, South AfricaMurison, Megan Kate January 2015 (has links)
[Partial abstract]: Human-wildlife conflict is a widely observed phenomenon and encompasses a range of negative interactions between humans and wildlife. Depredation upon livestock and game species proves to be the prevalent form of this conflict and often results in the killing of carnivores. Within the South African context, despite intense lethal control, two sympatric mesopredators, the blackbacked jackal (Canis mesomelas) and the caracal (Caracal caracal), remain common enough to be considered a major threat to human livelihoods through depredation. Wildlife ranches and livestock farms dominate the landscape in the Eastern Cape Province. Moreover, human-predator conflict within the region is extensive as both the black-backed jackal and caracal are seen to be inimical by landowners. Understanding this conflict is essential for mitigating any potential adverse environmental reactions (i.e. range collapses or extinctions) and requires knowledge of anthropogenic, ecological and environmental factors. I interviewed 73 land owners across five municipal boundaries in the Eastern Cape to quantify perceptions of predator control methods.
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An assessment of community understanding of the Human Animal Conservancy Self-Insurance Scheme and the impact of human-wildlife conflicts : a case study from the Kwandu conservancy, north-east Namibia.Kasaona, Marthin Kaukaha. January 2006 (has links)
The research problem of this mini-dissertation involves the conflicts between human and wildlife populations and the trialing of ‘compensation’ payouts that are emerging as a critical test within the conservancy. Crop raiders such as elephants, buffaloes, hippopotamus, bush pigs and small rodents, diminish farmers’ resource bases and cash crops, while carnivores are responsible for livestock losses. The aim of the research is to assess the level of community understanding of the compensation scheme and the impact of human wildlife interaction within the conservancy. This mini-dissertation investigated the level of community understanding about the Human Animal Conservancy Self-Insurance Scheme (HACSIS), and the impact of human-wildlife conflicts within the Kwandu Conservancy. Some of the research data were obtained from the conservancy game guards’ event book system, and the actual field research data were collected from the 1st August to 20th August 2006. The researcher conducted a total of 35 interviews, whereby 32 involved face-to-face interviews with single individuals, and 3 separate focus group discussions that consisted of four, five and two conservancy members. The interviews averaged 30 minutes in length. Each interview was preceded by a careful explanation of the purposes of the work, stressing that the intent was to evaluate their understanding and perceptions on HACSIS, the impact of human-wildlife conflicts and to explore better management strategies. The researcher has taken into account that the communities might exaggerate the wildlife problem based on his previous experience with the adjacent conservancy, in the hopes of gaining more compensation – they also use the researcher as a way to vent their frustration at the problem. On the assumption that there may be an element of exaggeration verification of these was obtained from the Event Book System (a manual book used by the Community Game Guards for recording both crops and livestock incidents on daily basis). This mini-dissertation reveals that 74.3 % (n = 26) of respondents are aware of the existence of the HACSIS program and its role, while 17.1 % of respondents had no idea about the scheme’s presence and its involvement to minimize the impact felt by communities when they lose livestock to predators. The percentage of respondents who claimed that they had heard of the scheme’s existence but had no knowledge of its role was 8.6 %. In addition, most respondents (n = 15) claimed that the conservancy committee did not explain to them why their claim forms were rejected. In contrast, some respondents (n = 6) did received feedback on rejected claim forms. HACSIS was not formed to compensate livestock losses based on market value, nor was it intended as a ‘compensation’ scheme. Its aim was to test a conservancy-run process – local verification of claims and monitoring by conservancy committee and traditional authority. In addition, the authorization of payments for a type of ‘self-insurance’ is drawn from conservancy income to partially offset the losses of conservancy members versus the overall gains that wildlife brings to the conservancy (direct conservancy income and local jobs through tourism, trophy hunting, own use game harvesting). Conservancy committees and the support NGO, IRDNC, agreed on the amount to be refunded for animal losses before the scheme was started, initially using donor funding in the trial phases. The amount was deliberately kept low as it was acknowledged from the start that conservancies themselves would take over the repayments from their own income. Once the conservancy was used to its own income to finance the scheme, conservancy members could vote to increase amounts paid for predator losses. The crucial aspect, according to IRDNC, was that the process itself be tested and that the scheme be run by the conservancy, with Ministry of Environment and Tourism and IRDNC merely monitoring and providing assistance as needed. Compensation is based on this pre-determined amount that is less than the livestock value. However, the research reveals that respondents (n = 19) were dissatisfied with the amount paid (N$ 800-00 per ox killed), because they claim that the amount paid to relieve the immediate impact from wildlife is too little to sustain the affected member. In contrast, some respondents (n = 8) were satisfied with the amount paid as compensation. Despite criticisms about the amount paid for livestock losses, none of the respondents (n = 22) who were familiar with the scheme wanted it to be abolished. The respondents emphasized the need for the conservancy committee to review the amount paid as compensation, especially for cattle. They suggested an increase from the current N$ 800-00 to N$ 1000-00 per ox loss. The research reveals that community livestock management practices have not changed to deliberately benefit from the compensation. In fact community management strategies have improved because of the condition set by the review committee dealing with the compensation scheme. Wildlife incidents have increased because animals are habituated to techniques used by communities to deter them and this has contributed to high livestock incidents. For human-wildlife conflicts, the research acknowledges that the conflict exists. Between 2003-2005, the Kwandu Conservancy reported 1508 incidents of damage to crops by wildlife. Species that were responsible included elephants with 30.2 % damage, bush pigs (29.8 %), hippopotamus (12.7%), antelopes (12.7 %), porcupine (7.5 %), and baboons/monkeys (7.2 %). Most of the crops destroyed by crop raiders, as suggested by the respondents, were maize (30 %), sorghum (26 %), millet (17 %), groundnuts (14 %), pumpkins (8 %) and beans (5%). During the same period of crop losses, the conservancy reported 98 livestock incidents. Animals responsible for livestock incidents were crocodile with 32 incidents (32.7 %), then hyena (23 incidents, 23.5 %), leopard (22 incidents, 22.4 %) and lion (21 incidents, 21.4%). The role of community game guards was found to be extensive. From a total 35 responses, 74.3 % (n = 26) of members stated that community game guards effectively record incidents, chased problem-causing animals from the community crop fields by shouting or shooting in the air, and assessed or verified killed livestock for compensation purposes. In addition, community game guards conduct crop assessment for record-keeping purposes. The scheme for crop compensation is to be introduced in 2007. Currently there is no proper formula to use in assessing the value of crops and the method to use to compensate the affected members. Other methods used by communities to deter wildlife include sleeping in the field to guard crops, cracking a whip, construction of human statues, hanging tins on the fence, chilli coils, watchtowers and digging trenches. Respondents had different views on the best management practices for problem-causing animals. The response was generally based on the degree of threat that the animal posed. Most (43.8 %, n = 14) preferred the monitoring of problem-causing animals that are sighted in an area as a best practice, while 40.6 % (n = 13) of respondents preferred the animal to be captured and relocated to parks. Only 25.6 % (n = 5) of respondents preferred that the animal be destroyed. The management practices preferred by respondents when an animal kills a person are different from when an animal is simply sighted in the area. If an animal kills a person, only 12.5 % (n = 4) of respondents preferred that the animal be captured and relocated to parks, while 87.5 % (n = 28) of respondents preferred the problem-causing animal to be destroyed. None of the respondents suggested monitoring as the best management option for this degree of threat. In conclusion, the research revealed that Human Animal Conservancy Self Insurance Scheme does not treat the cause of the problem but the symptom. This approach does not decrease the level of the problem given that the cause of the problem is not addressed. Therefore, the researcher stressed the need to fully explore and implement the recent piloted lion, crocodile fencing, and elephant proof fencing and elephants chilli coil to address and reduce the problem within Kwandu Conservancy. In addition, the research revealed that the scheme has very lengthy delays before compensation is paid and the review panel does not arrange meetings on the stipulated dates. This causes a back-log in the number of claims that need to be reviewed and approved. On Human Wildlife Conflict the research findings recommend the need to strengthen and improve existing problem-causing animal management strategies that are in place. Innovative strategies include reducing the number of stray livestock at night and developing static fences. Communities should be advised, as is being done by IRDNC, to herd their livestock during the day and to build strong kraals. This is the most effective and cheapest way to prevent livestock from being taken by predators at night. Further more the research revealed that the combination and rotation of the methods yield high success rather than deploying a single method over a long period, for the prevention of crop losses methods include guarding the crop field, cracking a whip, shooting in the air, watchtowers, human statues and beating drums. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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An assessment of caracal population density and human-predator conflict in the Winterberg, Eastern Cape, South AfricaSmith, Emma Ruth January 2012 (has links)
Human-wildlife conflict frequently involves carnivores, mainly because of their large home ranges and dietary requirements. As such, carnivores tend to be the first animals to be lost in human-dominated ecosystems. This is significant because the removal of carnivores can alter the functionality of ecosystems. However, the conservation of carnivores depends as much on the socio-political and socio-economic landscapes as it does on the ecological one. The consolidation of vast, un-fragmented conservation areas in Africa and the world is unlikely. Thus, unravelling the factors (both biological and sociological) responsible for and influencing human-predator conflict is critical for carnivore conservation. The Winterberg district in the Eastern Cape, South Africa has been a sheep (Ovis aries) farming stronghold for nearly 200 years. Consequently, conflict between farmers and predators is commonplace and depredation of livestock by caracals (Caracai caracal) remains a perennial problem. However, the extent of this human-predator conflict (including a reliable assessment of caracal density) has not been quantified. This study used camera trapping to estimate the density of caracals (a nonindividually recognisable species) in the Winterberg and a structured questionnaire to gauge the general attitudes of the farmers of the region. Caracal density was estimated to be 0.20 caracals/km². This estimate equates to a population of approximately 54 caracals across the entire district. Therefore, caracals do not appear to occur at high densities in the Winterberg. However, the survey of the residents of the Winterberg Conservancy revealed that predators were rated as the greatest problem faced by farmers in the area. Although not significant, it also showed that the size of a respondent's property and sheep mortality due to caracals had the greatest probability of affecting attitudes towards predators. The farmers lost less than 10% of their stock to caracal depredation on an annual basis. Therefore, the general perception that predators were the most important factor in stock loss in the area does not appear to be fully supported by my data. The Winterberg is a male-dominated, multigenerational society and it is likely this propagates certain perceptions towards predators which are a reflection of long-held family traditions and beliefs. Such situations can result in reactions which are disproportionate to the actual scale of the problem. However, my study was limited to a sub-set of the landowners in the Winterberg. Thus, more intensive assessments of caracal space use and community attitudes towards predators are recommended.
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