RESUMEN
Most species face multiple anthropogenic disruptions. Few studies have quantified the cumulative influence of multiple threats on species of conservation concern, and far fewer have quantified the potential relative value of multiple conservation interventions in light of these threats. We linked spatial distribution and population viability models to explore conservation interventions under projected climate change, urbanization, and changes in fire regime on a long-lived obligate seeding plant species sensitive to high fire frequencies, a dominant plant functional type in many fire-prone ecosystems, including the biodiversity hotspots of Mediterranean-type ecosystems. First, we investigated the relative risk of population decline for plant populations in landscapes with and without land protection under an existing habitat conservation plan. Second, we modeled the effectiveness of relocating both seedlings and seeds from a large patch with predicted declines in habitat area to 2 unoccupied recipient patches with increasing habitat area under 2 projected climate change scenarios. Finally, we modeled 8 fire return intervals (FRIs) approximating the outcomes of different management strategies that effectively control fire frequency. Invariably, long-lived obligate seeding populations remained viable only when FRIs were maintained at or above a minimum level. Land conservation and seedling relocation efforts lessened the impact of climate change and land-use change on obligate seeding populations to differing degrees depending on the climate change scenario, but neither of these efforts was as generally effective as frequent translocation of seeds. While none of the modeled strategies fully compensated for the effects of land-use and climate change, an integrative approach managing multiple threats may diminish population declines for species in complex landscapes. Conservation plans designed to mitigate the impacts of a single threat are likely to fail if additional threats are ignored.
Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales/métodos , Incendios , Plantones/fisiología , Urbanización , Región Mediterránea , Densidad de Población , Dinámica PoblacionalRESUMEN
PREMISE OF THE STUDY: Despite numerous recommendations for various aspects of the design and monitoring of habitat conservation plans, there remains a need to synthesize existing guidelines into a comprehensive scheme and apply it to real-world conservation programs. METHODS: We review tools for systematic conservation planning and elements for designing and implementing ecological monitoring in an adaptive management context. We apply principles of monitoring design to the San Diego Multiple Species Conservation Program (MSCP) in California, USA--one of the first multispecies habitat conservation plans, located in a landscape where high biodiversity and urban development converge. KEY RESULTS: Tools for spatial conservation planning are aimed to conserve biodiversity, often in the context of a limited budget. In practice, these methods may not accommodate legislative mandates, budgetary uncertainties, and the range of implementation mechanisms available across consortia of stakeholders. Once a reserve is implemented, the question becomes whether it is effective at conserving biodiversity, and if not, what actions are required to make it effective. In monitoring plan development, status and threats should be used to prioritize species and communities that require management action to ensure their persistence. Conceptual models documenting the state of knowledge of the system should highlight the main drivers affecting status and trends of species or communities. Monitoring strategies require scientifically justified decisions based on sampling, response, and data design. CONCLUSIONS: Because the framework illustrated here tackles multiple species, communities, and threats at the urban-wildland interface, it will have utility for ecosystem managers struggling to design monitoring programs.
Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , California , Especificidad de la EspecieRESUMEN
In many parts of the world, the combined effects of habitat fragmentation and altered disturbance regimes pose a significant threat to biodiversity. This is particularly true in Mediterranean-type ecosystems (MTEs), which tend to be fire-prone, species rich, and heavily impacted by human land use. Given the spatial complexity of overlapping threats and species' vulnerability along with limited conservation budgets, methods are needed for prioritizing areas for monitoring and management in these regions. We developed a multi-criteria Pareto ranking methodology for prioritizing spatial units for conservation and applied it to fire threat, habitat fragmentation threat, species richness, and genetic biodiversity criteria in San Diego County, California, USA. We summarized the criteria and Pareto ranking results (from west to east) within the maritime, coastal, transitional, inland climate zones within San Diego County. Fire threat increased from the maritime zone eastward to the transitional zone, then decreased in the mountainous inland climate zone. Number of fires and fire return interval departure were strongly negatively correlated. Fragmentation threats, particularly road density and development density, were highest in the maritime climate zone, declined towards the east, and were positively correlated. Species richness criteria showed distributions among climate zones similar to those of the fire threat variables. When using species richness and fire threat criteria, most lower-ranked (higher conservation priority) units occurred in the coastal and transitional zones. When considering genetic biodiversity, lower-ranked units occurred more often in the mountainous inland zone. With Pareto ranking, there is no need to select criteria weights as part of the decision-making process. However, negative correlations and larger numbers of criteria can result in more units assigned to the same rank. Pareto ranking is broadly applicable and can be used as a standalone decision analysis method or in conjunction with other methods.
Asunto(s)
Biodiversidad , Clima , Conservación de los Recursos Naturales/métodos , Ecosistema , Incendios Forestales , CaliforniaRESUMEN
Poor communication between academic researchers and wildlife managers limits conservation progress and innovation. As a result, input from overlapping fields, such as animal behaviour, is underused in conservation management despite its demonstrated utility as a conservation tool and countless papers advocating its use. Communication and collaboration across these two disciplines are unlikely to improve without clearly identified management needs and demonstrable impacts of behavioural-based conservation management. To facilitate this process, a team of wildlife managers and animal behaviour researchers conducted a research prioritisation exercise, identifying 50 key questions that have great potential to resolve critical conservation and management problems. The resulting agenda highlights the diversity and extent of advances that both fields could achieve through collaboration.
Asunto(s)
Animales Salvajes , Conservación de los Recursos Naturales , Animales , Conducta Animal , Humanos , Investigación , InvestigadoresRESUMEN
Successful conservation plans are not solely achieved by acquiring optimally designed reserves. Ongoing monitoring and management of the biodiversity in those reserves is an equally important, but often neglected or poorly executed, part of the conservation process. In this paper we address one of the first and most important steps in designing a monitoring program - deciding what to monitor. We present a strategy for prioritizing species for monitoring and management in multispecies conservation plans. We use existing assessments of threatened status, and the degree and spatial and temporal extent of known threats to link the prioritization of species to the overarching goals and objectives of the conservation plan. We consider both broad and localized spatial scales to capture the regional conservation context and the practicalities of local management and monitoring constraints. Spatial scales that are commensurate with available data are selected. We demonstrate the utility of this strategy through application to a set of 85 plants and animals in an established multispecies conservation plan in San Diego County, California, USA. We use the prioritization to identify the most prominent risk factors and the habitats associated with the most threats to species. The protocol highlighted priorities that had not previously been identified and were not necessarily intuitive without systematic application of the criteria; many high-priority species have received no monitoring attention to date, and lower-priority species have. We recommend that in the absence of clear focal species, monitoring threats in highly impacted habitats may be a way to circumvent the need to monitor all the targeted species.