The Okavango Delta is the largest inland delta in the world and supports a vast array of critical ecosystem services within an otherwise semi-arid region of northern Botswana. Biodiversity values are one of the highest in southern Africa, and an important tourism economy in the region is based upon viewing opportunities that focus on a diversity of wildlife species. Biodiversity, including viewable wildlife, represent critical and potentially sensitive ecosystem values and services.
Aerial wildlife surveys completed in 2010 documented a dramatic decline in several ungulate species across the region, with the potential causes of these declines unknown. Possible causes to the declines may include poaching, habitat fragmentation and changes in habitat availability due to changing flood regimes; other researchers have also suggested linkages to the long term drought the area has experienced. Consequently, there is a need to develop a regional understanding of the distribution and availability of habitats for key wildlife species and how these habitats may change under different future scenarios including climate-induced changes in vegetation.
Significant research efforts have been undertaken in the Delta on the dynamic relationships between flooding regimes and vegetation, groundwater levels and vegetation and on predicted climate-induced changes in vegetation distributions. There is also a significant amount of ecological research and inventory information on a number of ungulate species. Synthesizing these disparate efforts can provide an initial regional perspective on the current abundance, distribution and availability of habitats for key wildlife species through species habitat modeling. Additionally, linking existing models of vegetation conditions under future climate-induced conditions to species habitat models provides an opportunity to complete initial assessments of how habitats for identified species may change in quantity, quality and potentially distribution. Such analyses would assist decision-making for habitat and wildlife management in the Delta.
The study area is the area encompassed by the Moremi Game Reserve and the Wildlife Management Areas of the Delta.
This effort involves two major phases, with stand-alone deliverables anticipated for each.
During Phase 1, deliverables will be based entirely upon best available existing information on vegetation classification across the study area and best available information and data on the seasonal habitat requirements of selected ungulate species. Species will be selected based on their generalized habitat associations such that the suite of species represents the diversity of key ecosystems across the study area.
Phase 1 deliverables are anticipated to include:
• compilation of best available spatial and non-spatial data on vegetation classes and their distribution;
• compilation of best available spatial and non-spatial data and information on selected ungulate species; -development of seasonal habitat models (e.g., wet season, dry season models) for species with sufficient information, with modeling approach and resolution based on available information and resources;
• prediction of the current relative amount and distribution of seasonal habitats for selected species based on best available vegetation models and generalized or specific assumptions regarding key environmental drivers (e.g., flooding levels, rainfall conditions);
• habitat models may be applied partially or fully to existing predictions of vegetation conditions under climate change scenarios; this will be dependent upon availability and quality of existing data on vegetation predictions. These analyses will emphasize identifying the potential change in habitat quantity and possibly major shifts in distributions; and
• report documenting assumptions, methods, results and limitations of the effort, as well as recommendations for next steps and management applications.
The data compilation, synthesis and model development undertaken in Phase 1 will be used to identify critical information gaps in our ability to understand and model current and potential future habitat distributions for key wildlife species in the Delta. A proposal for increasing the rigor and scientific robustness of analyses will be developed near the completion of the Phase 1. It is anticipated that Phase 2 will include a proposal to incorporate on-going field data collection efforts to increase the robustness and precision of existing vegetation modeling, examine and potentially link population relative abundance and structure data to habitat predictions or regional distributions and develop decision-support tools including a regional conservation area design identifying key areas for wildlife conservation under current and future conditions.