The Red Sea Project

Our conservation models assessed two groups of scenarios, one including conservation only and one examining conservation in the presence of development. The rationale of this grouping was to explore the nexus of conservation and development in the area, thus challenging the project pledge to achieve net positive conservation impact through thoughtful sustainable development. In particular, we created five scenarios: three scenarios considering only conservation, based on three increasingly comprehensive groups of conservation targets (six habitats of high conservation value, all habitats, other than the terrestrial ones and the deep open ocean, and all habitats plus 11 species of high conservation value, i.e., two sea turtle species and nine bird species), without considering any development plans. By progressively adding conservation targets to the analysis, we assessed whether targeting the most valuable habitats provided a surrogate for broader conservation targets, as assessed in the past, including the Red Sea. We note that only birds and sea turtle species of conservation concern were explicitly considered among the hundreds of species present in the area. The reason for this was that birds and turtles have vulnerable stages (i.e., nesting) of their life cycles on land, where marine habitats are not defined. We also evaluated two scenarios to assess if similar conservation targets as those in the absence of development could be achieved in the presence of development. The first scenario of this group entailed all habitats and species (as per scenario Cons_h+s) but also considered the development elements as areas a priori excluded from conservation. In the second scenario of this group, the nine islands decided by TRSDC to be set aside for protection were also included in the analysis, as a priori selected for conservation in order to evaluate how this decision quantitatively affects the final conservation outcome. All scenarios were processed using the software-based decision support tool Marxan v 2.43 to select areas for conservation. The study area was divided in 32,398 square PUs of 0.25 km² each. The dimensions of the PUs (500 m × 500 m) were defined by the spatial accuracy of the available data and the desired analysis output (i.e., to fit the buffer zone around species’ nests; 500 m; decided by the experts on the environmental alignment workshops). We set Marxan to retain 99 and 90% of the area of high-value habitats (six habitats, all five scenarios) within conservation zones. In addition, we prescribed 50–80% of the area of other habitats (11, in four of the scenarios) to be retained within the conservation zones. Similarly, Marxan was used to conserve 90 and 100% of high-value nesting habitat (for the high-priority species) and 70% of low-value nesting habitat for each of the 11 priority conservation species included within conservation zones. 

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The PUs selected by Marxan for each of the five scenarios were needed to meet the set of conservation targets, but they likely differed in their individual contribution to this target, as inspection of the base habitat and nesting map shows that many habitats and species of high conservation value tend to co-occur. We, therefore, developed a methodology to estimate the cumulative conservation value of each scenario, as well as the contribution of each individual PU selected to this total value. This was achieved by assigning a discrete conservation value ranging from 0.5 to 5 to each habitat and species conforming to the scenario, with the conservation value being positively correlated to the conservation target (e.g., a species with the maximum conservation target of 100% target bears the maximum conservation value of 5). More explicitly, for each PU selected for protection, the percentage of each ecological feature contained in this PU with respect to the total area of the feature selected for conservation in the scenario was calculated. This ratio was multiplied to the preassigned conservation value of the feature. The sum of all these products provides the conservation value of each PU. The sum of the conservation values of all the selected PUs resulted in the cumulative conservation value of the scenario. The latter allowed for the visualization of the most “valuable” cells as well as the quantitative assessment of what it is conserved by Marxan per scenario.

We succeeded in creating a three-layer conservation zoning, achieving conservation outcomes as those possible in the “business as usual” scenario. We identified that the conservation zoning of the TRSP emerging from the MSP exercise, including iterative workshops to avoid impacts through changes in design and conservation modeling reaches similar conservation outcomes in the presence of development as if the whole area was declared an MPA (1,219 km² conservation area required). The “top conservation zone” consists of the PUs (20% of the total 32,399 PUs) included in the two highest classes of the quantile separation, comprising cells within the upper 40% of the range of conservation scores of the selected PUs. The “top conservation zone” contains the most valuable cells according to the classification and refers to the most important habitats and should be dedicated only to conservation, research and monitoring. Only guided tours of small groups of visitors for educational purposes would be permitted in this area. The “high conservation zone” formed by the PUs comprising the lower 60% of the range of conservation scores of the selected PUs include 30% of the total 32,399 PUs. This zone will be subject to severe restrictions defining the mobility of humans, the transportation means, and the infrastructure permitted. No permanent structures would be developed within the boundaries of this zone (e.g., hotels or jetties). Finally, the “development zone” (5% of the total PUs) accommodates all the development elements and activities. However, this zone is also facing limitations as the whole area of the lagoon is defined as critical habitat. These include specific buffer zones around vulnerable habitats and nesting sites and strict management of light, noise, and litter.  Subsequently, TRSDC designed additional actions to remove existing pressures and generate net positive conservation outcomes. For instance, all transport will be conducted by electric vehicles, power will be generated by renewable technologies, single-use plastic will be banned, no brine will be discharged within the lagoon, 100% of freshwater will be reused (other than evaporative losses), and recycling aims at no waste to landfills. Indeed, TRSP pledges an increase in net conservation value, of 30% in 20 years compared to the “business as usual” scenario. The results demonstrate that careful design and planning could potentially allow coastal development to enhance, rather than jeopardize, conservation.