Brodie J.F.,University of Montana |
Muntifering J.,Apple Inc |
Hearn M.,Save the Rhino Trust |
Hearn M.,University of Kent |
And 6 more authors.
Curtailing overharvest, whether illegal or legal, is often a critical conservation objective. Yet even if overexploitation can be stopped, subsequent rates of population recovery can be highly variable due to Allee effects, alterations to age and sex structure and disruptions of animal social systems. Moreover, understanding the influence of density dependence can be difficult but important for long-term management. Here, we investigate the dynamics of black rhinoceros Diceros bicornis in the Kunene region of Namibia as they recover from illegal hunting. We use multi-strata mark-recapture models to examine survival and stage-transition rates from 1992 to 2005. Survivorship estimates ranged from 0.793 for calves to 0.910 for adult males and 0.944 for adult females. The annual reproductive rate in adult females was estimated at 0.315. Model selection showed that these vital rates were time invariant, suggesting that Allee effects and transient dynamics did not have an important effect upon population dynamics, even in the early stages of recovery. Relative population density increased significantly from 1992 to 2005 once illegal hunting had ceased in Kunene. However, the best-fit models did not include relative density in the estimation of survival or stage-transition rates. We then used the vital rates generated from our mark-recapture analysis to build matrix projection models that assessed overall population dynamics. The female-only model gave a population growth rate estimate of λ=1.011. Two-sex models suggest that the growth rate of the population could range from 0.990 to 1.012. The relatively slow growth rate of this population, even without hunting or density dependence, could stem from the low productivity of the region. Adult females had the highest reproductive value and their survival had the highest elasticity among vital rates. Translocating adult females would lead to the fastest initial population growth rate in founder populations but would have the most impact on the source population. © 2011 The Authors. Animal Conservation © 2011 The Zoological Society of London. Source
Muntifering J.R.,Apple Inc |
Linklater W.L.,Victoria University of Wellington |
Clark S.G.,Yale University |
!Uri-=Khob S.,Save the Rhino Trust |
And 11 more authors.
The rate at which the poaching of rhinoceroses has escalated since 2010 poses a threat to the long-term persistence of extant rhinoceros populations. The policy response has primarily called for increased investment in military-style enforcement strategies largely based upon simple economic models of rational crime. However, effective solutions will probably require a context-specific, stakeholder-driven mix of top-down and bottom-up mechanisms grounded in theory that represents human behaviour more realistically. Using a problem-oriented approach we illustrate in theory and practice how community-based strategies that explicitly incorporate local values and institutions are a foundation for combating rhinoceros poaching effectively in specific contexts. A case study from Namibia demonstrates how coupling a locally devised rhinoceros monitoring regime with joint-venture tourism partnerships as a legitimate land use can reconcile individual values represented within a diverse stakeholder group and manifests as both formal and informal community enforcement. We suggest a social learning approach as a means by which international, national and regional governance can recognize and promote solutions that may help empower local communities to implement rhinoceros management strategies that align individual values with the long-term health of rhinoceros populations. Copyright © Fauna & Flora International 2015 Source