Simulating range shifts of African mammals under predicted climate change: potential conservation and economic consequences

Abstract

Simulated present-day ranges of 281 African mammal species were produced using climate-envelope models. This modeling approach was robust and was therefore used to simulate potential future ranges of 281 African mammals in response to nine future climate change scenarios (three general circulation models for 2020, 2050 and 2080). The size of species' ranges were projected to decrease only slightly (-4.41%) on average by 2080. Species' future ranges were projected to overlap current ranges by only 75.7% on average by 2080.The effectiveness of the African protected area (PA) network under projected future climate change was then assessed by intersecting simulated ranges with PA outlines at the quarter degree scale. By 2080, the mean decrease in species richness was projected to be 7.18% under a best-case scenario of range shift, which is greater that that projected for areas of Africa beyond р As (-4.41%). By 2080, mean species persistence and turnover within РAs were projected to be, on average, 79% and 26% respectively. Species turnover will be unevenly spread across the PA network; PAs in South Africa and Namibia will be affected most by climate change. Simulations indicated the loss of keystone and charismatic species from a number of PAs, including Kruger National Park (KNP). The value of two keystone species in KNP was assessed using the contingent valuation method. Significant factors influencing willingness-to-pay included respondents' age, employment status and experience of visiting the PA. Aggregated willingness-to-pay values were R87.3million (±R17.4million) per year for ensemble species conservation, R41.1 million (± R17.8million) for giraffe (Giraffa camelopardalis) and R42.4million (± R14.3million) for elephant (Loxodonta africana) conservation. Until greenhouse gas emissions are stabilised (or reduced), it is inevitable that further climate change, and therefore further alterations of species distributions will occur. Efforts such as increasing the extent and connectedness of the PA network may help to protect species threatened by projected climate change by allowing them the opportunity of tracking climate change.