Mapping of biodiversity hubs and key ecosystem services as a tool for shaping optimal areas for conservation

to provide habitat for endangered wildlife but also to contribute to many other functions among which are to sustain the livelihood of local communities, to support national economies through tourism revenues, to replenish fisheries, and to play a key part in the mitigation of cli- mate change. Although the expanded role of PA may have fueled their establishment, their constantly widening focus makes them vulnerable to accusations of failure to achieve one or more of these objectives [3]. Many PA are either too small to serve their intended functions, too damaged to support conservation purposes, or are not located in areas of the most signifi- cant conservation value. Serious deficiencies in the structure and location of PA were raised by numerous studies in different parts of the world. Liang et al. [4] have pointed out loopholes at PA location and top priority conservation areas, while Xu et al. [5] found a surprising diver- gence between the location of established PA and endangered biodiversity hubs on one hand and key ES on the other hand. Myers [6] coined the term ‘biodiversity hotspot’ as a biogeo- graphic region characterized both by exceptional concentrations of species with high levels of endemism and by serious levels of habitat loss. According to Myers et al. [7], and Joppa et al. [8] to qualify as a hotspot, a region must meet two strict criteria: It must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics, and it has to have lost at

least 70% of its original habitat. Biodiversity hotspots, as well as other global biodiversity prior- ity schemes such as Global ecoregions, and High-Biodiversity Wilderness Areas (HBWAs) pri- marily aim to ensure the efficiency use of conservation investments [9, 10]. For decades, conservationists have recognized that rare plants are clustered into small and isolated habitat patches produced by landscape features [11]. As Myers et al. [7] put it, Rwanda is among regions that appear to feature exceptional plant endemism and exceptional threat, but that are not sufficiently documented to meet the hotspots criteria. For this reason, ‘biodiversity hub’ terminology will be used to express a biogeographic region with significant levels of endemic biodiversity that is threatened by anthropologic activities Weaknesses at protecting such important regions have been raised by different authors. Mountain ranges, for instance, con- stitute biodiversity hubs, particularly for montane species but existing protection systems fail to fully capture montane biodiversity patterns or facilitate species range shifts [12–14]. By con- trast, the common preference to protect ‘wild’ areas, thanks to their easier opportunities for the future expansion of PA compared to the greater challenges of expansion into human-dom- inated landscapes, in most of the cases brings people to choose remote, cold, or arid areas con- sequently holding few species to protect [15]. This paper makes a contribution towards a better understanding of the linkage between

PA, biodiversity conservation, ES, and human wellbeing, as a necessary step towards ensuring more effective and sustainable integration of ecological portion into other so many national development imperatives. It unpacks some of the home-grown realities of these linkages through the application of a multidimensional conservation approach. By doing so, it responds to five current weaknesses that are common in today’s conservation analysis in Rwanda as it has been raised by various authors [16–19]. These weaknesses are the following: 1. Focusing on the protection of certain preferred species instead of ecosystems. Yet PA are not meant to protect isolated species but the entire ecosystems. 2. Limited recourse to modern technology to correct the status quo that was established dur- ing the past when there was lack of adequate tools, even when the lack of objectivity and inefficiency are palpable. 3. Allowing much more attention to the direct income-generation side of conservation and leave behind the mission to transfer the natural heritage to the next generation in unim- paired state. PLOS ONE How do old national parks cope with regenerating conservation mission? PLOS ONE | https://doi.org/10.1371/journal.pone.0253151 August 17, 2021 2 / 20