72 research outputs found
How to make land subdivision work : An analysis of the ecological and socio-economic factors affecting conservation outcomes dureing land privatisation in Kenyan Maasiland
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Impact of Land Subdivision and Sedentarization on Wildlife in Kenya’s Southern Rangelands
Subdivision and sedentarization of pastoral communities is accelerating rapidly across the African rangelands, posing a severe threat to wildlife populations, but few studies have looked quantitatively at the ecological impact of sedentarization. Here we look at the impact of sedentarization on wildlife by comparing ecologically matched subdivided and unsubdivided Maasai pastoral lands (ranches) in semiarid southern Kenya. We found no significant difference in livestock densities on the two ranches but there was a significantly higher wildlife density on the unsubdivided ranch, in both dry and wet seasons. Nonetheless, the unsubdivided ranch still had a higher percentage of grass biomass and ground cover and lower grazing pressure than the subdivided ranch. Distribution of homesteads (bomas) was mostly random on the subdivided ranch, with little area unaffected by human settlement. On the contrary, the unsubdivided ranch had a highly clumped boma distribution pattern, resulting in much of the land being relatively far from permanent human settlement. We show that the regular distribution and permanence of settlements following subdivision and sedentarization greatly reduces wildlife populations both through direct displacement and a reduction of forage. Relative to mobile pastoralism on open rangelands, sedentarization leads to reduced seasonal movements of livestock, lowered grass biomass, and slower grass recovery after very dry periods. This study points to the need to maintain mobile, large-scale herd movements to avoid the heavy impact on grasslands associated with sedentarization of pastoral settlement and herds.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
Finding a safe space: denning range dynamics of African wild dogs in Zimbabwe
African wild dogs utilise a den for ~10–12 weeks after birthing, during which home ranges are contracted and usually in areas away from roads and water sources, with low prey and predator abundances, high terrain ruggedness and vegetation cover. Our study in Savé Valley Conservancy (SVC) investigated which ecological and environmental factors determine the selection of denning areas and behaviours. Camera trap data collected from four den grids and three random den grids were analysed using binomial generalised linear and occupancy models. Denning wild dogs preferred areas with higher kudu and impala presence and areas closer to roads and water sources. Wild dogs may den in areas we perceive as riskier in an attempt to reduce energy expenditure when hunting. The detection of wild dogs strongly decreased with higher lion presence, while increasing with steeper slopes, higher vegetation cover and leopard presence. Given lion habitat preferences, SVC wild dogs could be using areas which reduce their exposure to lions, while solitary leopards do not necessarily pose a risk to wild dog packs. Our study highlights that the denning behaviours of wild dogs may be inconsistent both within and among populations, and that comprehensive research approaches be taken to understand their denning behaviours, assisting the development of appropriate management/conservation strategies
Evaluation of the applicability of different age determination methods for estimating age of the endangered African wild dog (Lycaon Pictus)
African wild dogs (Lycaon pictus) are endangered and their population continues to decline
throughout their range. Given their conservation status, more research focused on their
population dynamics, population growth and age specific mortality is needed and this
requires reliable estimates of age and age of mortality. Various age determination methods
from teeth and skull measurements have been applied in numerous studies and it is fundamental
to test the validity of these methods and their applicability to different species. In this
study we assessed the accuracy of estimating chronological age and age class of African
wild dogs, from dental age measured by (i) counting cementum annuli (ii) pulp cavity/tooth
width ratio, (iii) tooth wear (measured by tooth crown height) (iv) tooth wear (measured by
tooth crown width/crown height ratio) (v) tooth weight and (vi) skull measurements (length,
width and height). A sample of 29 African wild dog skulls, from opportunistically located carcasses
was analysed. Linear and ordinal regression analysis was done to investigate the
performance of each of the six age determination methods in predicting wild dog chronological
age and age class. Counting cementum annuli was the most accurate method for estimating
chronological age of wild dogs with a 79% predictive capacity, while pulp cavity/
tooth width ratio was also a reliable method with a 68% predictive capacity. Counting
cementum annuli and pulp cavity/tooth width ratio were again the most accurate methods
for separating wild dogs into three age classes (6±24 months; 25±60 months and > 60
months), with a McFadden's Pseudo-R2 of 0.705 and 0.412 respectively. The use of the
cementum annuli method is recommended when estimating age of wild dogs since it is the
most reliable method. However, its use is limited as it requires tooth extraction and shipping,
is time consuming and expensive, and is not applicable to living individuals. Pulp cavity/tooth width ratio is a moderately reliable method for estimating both chronological age
and age class. This method gives a balance between accuracy, cost and practicability,
therefore it is recommended when precise age estimations are not paramount.S1 Fig. Raw data for themanuscript. This is the raw data used in all the analysis in this manuscript.This work was funded by grants awarded
to RJG from National Geographic Conservation
Trust, Columbus Zoo and Aquarium, Disney
Worldwide Conservation Fund and The Rufford
Foundation.http://www.plosone.orgam2016Companion Animal Clinical Studie
Ecological and financial impacts of illegal bushmeat trade in Zimbabwe
Under conditions of political instability and
economic decline illegal bushmeat hunting has emerged
as a serious conservation threat in Zimbabwe. Following
settlement of game ranches by subsistence farming communities,
wildlife populations have been eradicated over
large areas. In several areas still being managed as game
ranches illegal hunting is causing further declines of
wildlife populations (including threatened species such as
the wild dog Lycaon pictus and black rhinoceros Diceros
bicornis), threatening the viability of wildlife-based land
uses. From August 2001 to July 2009 in Save´ Valley
Conservancy 10,520 illegal hunting incidents were recorded,
84,396 wire snares removed, 4,148 hunters caught,
2,126 hunting dogs eliminated and at least 6,454 wild
animals killed. Estimated future financial losses from illegal
hunting in the Conservancy exceed USD 1.1 million year-1.
Illegal hunters’ earnings account for 0.31–0.52% of the
financial losses that they impose and the bushmeat trade is
an inefficient use of wildlife resources. Illegal hunting
peaks during the late dry season and is more frequent
close to the boundary, near areas resettled during land
reform and close to water. Illegal hunting with dogs peaks
during moonlight periods. Our study highlights several
management and land-use planning steps required to
maximize the efficacy of anti-poaching and to reduce the
likelihood of high impacts of illegal hunting. Anti-poaching
efforts should be aligned with the regular temporal and
spatial patterns of illegal hunting. Leases for hunting and
tourism concessions should ensure minimum adequate
investment by operators in anti-poaching. Reserve designers
should minimize the surface area to volume ratio of parks.
Fences should not be constructed using wire that can be
made into snares. Land reform involving game ranches
should integrate communities in wildlife-based land uses and ensure spatial separation between land for wildlife and
human settlement. Means are required to create stakeholdings
for communities in wildlife and disincentives for
illegal hunting.TRAFFIC Southern and East Africa, the
European Union, Wilderness Trust, Chicago Board of
Trade and the supporters of the African Wildlife Conservation
Fund.http://journals.cambridge.orgab201
Fostering Coexistence Between People and Large Carnivores in Africa: Using a Theory of Change to Identify Pathways to Impact and Their Underlying Assumptions
Coexistence with large carnivores poses challenges to human well-being, livelihoods, development, resource management, and policy. Even where people and carnivores have historically coexisted, traditional patterns of behavior toward large carnivores may be disrupted by wider processes of economic, social, political, and climate change. Conservation interventions have typically focused on changing behaviors of those living alongside large carnivores to promote sustainable practices. While these interventions remain important, their success is inextricably linked to broader socio-political contexts, including natural resource governance and equitable distribution of conservation-linked costs and benefits. In this context we propose a Theory of Change to identify logical pathways of action through which coexistence with large carnivores can be enhanced. We focus on Africa’s dryland landscapes, known for their diverse guild of large carnivores that remain relatively widespread across the continent. We review the literature to understand coexistence and its challenges; explain our Theory of Change, including expected outcomes and pathways to impact; and discuss how our model could be implemented and operationalized. Our analysis draws on the experience of coauthors, who are scientists and practitioners, and on literature from conservation, political ecology, and anthropology to explore the challenges, local realities, and place-based conditions under which expected outcomes succeed or fail. Three pathways to impact were identified: (a) putting in place good governance harmonized across geographic scales; (b) addressing coexistence at the landscape level; and (c) reducing costsand increasing benefits of sharing a landscape with large carnivores. Coordinated conservation across the extensive, and potentially transboundary, landscapes needed by large carnivores requires harmonization of top-down approaches with bottom-up community-based conservation. We propose adaptive co-management approaches combined with processes for active community engagement and informed consent as useful dynamic mechanisms for navigating through this contested space, while enabling adaptation to climate change. Success depends on strengthening underlying enabling conditions, including governance, capacity, local empowerment, effective monitoring, and sustainable financial support. Implementing the Theory of Change requires ongoing monitoring and evaluation to inform adaptation and build confidence in the model. Overall, the model provides a flexible and practical framework that can be adapted to dynamic local socio-ecological contexts. large carnivore conservation, African semi-arid, community-based conservation, human wildlife conflict, community-based natural resource management, adaptive co-management, rangeland management, climate change adaptationpublishedVersio
SEASTAR: a mission to study ocean submesoscale dynamics and small-scale atmosphere-ocean processes in coastal, shelf and polar seas
High-resolution satellite images of ocean color and sea surface temperature reveal an abundance of ocean fronts, vortices and filaments at scales below 10 km but measurements of ocean surface dynamics at these scales are rare. There is increasing recognition of the role played by small scale ocean processes in ocean-atmosphere coupling, upper-ocean mixing and ocean vertical transports, with advanced numerical models and in situ observations highlighting fundamental changes in dynamics when scales reach 1 km. Numerous scientific publications highlight the global impact of small oceanic scales on marine ecosystems, operational forecasts and long-term climate projections through strong ageostrophic circulations, large vertical ocean velocities and mixed layer re-stratification. Small-scale processes particularly dominate in coastal, shelf and polar seas where they mediate important exchanges between land, ocean, atmosphere and the cryosphere, e.g., freshwater, pollutants. As numerical models continue to evolve toward finer spatial resolution and increasingly complex coupled atmosphere-wave-ice-ocean systems, modern observing capability lags behind, unable to deliver the high-resolution synoptic measurements of total currents, wind vectors and waves needed to advance understanding, develop better parameterizations and improve model validations, forecasts and projections. SEASTAR is a satellite mission concept that proposes to directly address this critical observational gap with synoptic two-dimensional imaging of total ocean surface current vectors and wind vectors at 1 km resolution and coincident directional wave spectra. Based on major recent advances in squinted along-track Synthetic Aperture Radar interferometry, SEASTAR is an innovative, mature concept with unique demonstrated capabilities, seeking to proceed toward spaceborne implementation within Europe and beyond
Guidelines for evaluating the conservation value of African lion (Panthera leo) translocations
As the top predator in African ecosystems, lions have lost more than 90% of
their historical range, and few countries possess strong evidence for stable
populations. Translocations (broadly defined here as the capture and
movement of lions for various management purposes) have become an
increasingly popular action for this species, but the wide array of lion
translocation rationales and subsequent conservation challenges stemming
from poorly conceived or unsuitable translocations warrants additional
standardized evaluation and guidance. At their best, translocations fill a key
role in comprehensive strategies aimed at addressing the threats facing lions
and fostering the recovery of wild populations in their historic range. At their
worst, translocations can distract from addressing the major threats to wild
populations and habitats, divert scarce funding from more valuable
conservation actions, exacerbate conflict with humans in recipient sites,
disrupt local lion demography, and undermine the genetic integrity of wild
lion populations in both source and recipient sites. In the interest of developing
best practice guidelines for deciding when and how to conduct lion
translocations, we discuss factors to consider when determining whether a
translocation is of conservation value, introduce a value assessment for
translocations, and provide a decision matrix to assist practitioners in
improving the positive and reducing the negative outcomes of
lion translocation.Grant from the European Union through IUCN Save Our Species, and the United States Fish and Wildlife Service.https://www.frontiersin.org/journals/conservation-scienceam2023Zoology and Entomolog
Wild dog reproductive success at our Zimbabwe study site
This file shows, for our Zimbabwe study area, the number of pups raised to three months of age in each breeding attempt, the number that survived to 12 months, and various potential covariates
Insights into the Management of Large Carnivores for Profitable Wildlife-Based Land Uses in African Savannas
Large African predators, especially lions (Panthera leo) and leopards (Panthera pardus), are financially valuable for
ecotourism and trophy hunting operations on land also utilized for the production of other wildlife species for the same purpose. Predation of ungulates used for trophy hunting can create conflict with landholders and trade off thus exists between the value of lions and leopards and their impact on ungulate populations. Therefore productionist and conservation trade-offs are complexly graded and difficult to resolve. We investigated this with a risk-benefit analysis on a large private wildlife production area in Zimbabwe. Our model showed that lions result in substantial financial costs
through predation on wild ungulates that may not be offset by profits from hunting them, whereas the returns from trophy hunting of leopards are projected to exceed the costs due to leopard predation. In the absence of additional income derived from photo-tourism the number of lions may need to be managed to minimize their impact. Lions drive important ecological processes, but there is a need to balance ecological and financial imperatives on wildlife ranches, community wildlife lands and other categories of multiple use land used for wildlife production. This will ensure the competitiveness of
wildlife based land uses relative to alternatives. Our findings may thus be limited to conservancies, community land-use areas and commercial game ranches, which are expansive in Africa, and should not necessarily applied to areas where biodiversity conservation is the primary objective, even if hunting is allowed there
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