Future hotspots of terrestrial mammal loss

Piero Visconti () 1 2 Robert L. Pressey 2 Daniele Giorgini 1 Luigi Maiorano 0 Michel Bakkenes 3 Luigi Boitani 1 Rob Alkemade 3 Alessandra Falcucci 1 Federica Chiozza 1 Carlo Rondinini 1 0 Department of Ecology and Evolution, University of Lausanne , Lausanne , Switzerland 1 Global Mammal Assessment programme, Department of Biology and Biotechnology, Sapienza University of Rome , Italy 2 ARC Centre of Excellence for Coral Reef Studies, James Cook University , Townsville, Queensland , Australia 3 Netherlands Environmental Assessment Agency (PBL) , The Hague , The Netherlands Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world. 1. INTRODUCTION Since the 1500s, 76 species and seven subspecies of mammals have gone extinct and another two are only extant in captivity. The hotspots of extinctions during this period have been Australia (because of direct killing, invasive rats, foxes, cats, habitat loss), the Caribbean (invasive rats and mongoose, direct killing) and South-Pacific islands (direct killing, invasive rats and snakes) [1]. Despite some conservation successes [2], most species are still declining, including a further 29 that may already be extinct such as the Christmas Island Pipistrelle Pipistrellus murrayi, the Kouprey Bos sauveli and the Baiji dolphin Lipotes vexillifer [3]. Twenty-five per cent (n 1144) of all mammals for which there is sufficient information for an assessment of conservation status are threatened with extinction. The largest concentration of threatened terrestrial species is in South and Southeast Asia, the tropical Andes in South America, the Cameroonian Highlands and Albertine Rift in Africa, and the Western Ghats in India. All these regions combine high species richness, high numbers of range-restricted species [3] and high human pressure [4]. Threatened marine species are concentrated in the North Atlantic, the North Pacific and Southeast Asia, and these are also areas of concentration of range-restricted species [3] and high human impact [5]. Worldwide, the main threats to mammals are habitat loss and degradation (affecting 40% of all mammals) and harvesting (hunting or gathering for food, medicine and materials, affecting 19%). Among the drivers of habitat loss for mammals, agriculture and pastoralism are the most important, together affecting 40 per cent of terrestrial mammals (n 2089) [1]. Recently, agriculture and grazing have expanded almost exclusively in the tropics [6]. Between 1980 and 2000, cattle pastureland increased by approximately 35 million ha in South America and approximately 7 million ha in Central America [7]. Cropland area increased by approximately 5 million ha in South America, further fragmenting and reducing the natural habitats of the Llanos of Venezuela, the Atlantic forest of Brazil, the Cerrado and the Amazon. In Southeast Asia, most agricultural expansion during the same period has been for tree plantations, which increased from roughly 11 to 17.4 million ha [7]. Oil palm Elaeis guineensis plantations increased tenfold from 0.2 to 2.7 million ha in Borneo alone. These plantations pose a serious threat to many endangered species such as the Bornean Orangutan Pongo pygmaeus, with remaining populations occurring mostly outside protected areas in lowland areas of high suitability for oil palm [1]. In the period 19802000, cropland area increased by approximately 50 and 25 per cent in East Africa and West Africa, respectively. Globally, between 1995 and 2007, agricultural land increased by 400 million ha in developing countries but decreased by 412 million ha in developed countries [7]. The vast majority of this new agricultural land has come at the expense of native vegetation, particularly primary forest where clearing gives the added benefit of timber products [6]. Worryingly, this agricultural expansion is expected to continue in the future. Demand for agricultural products is predicted to increase by up to 50 per cent by 2050, with most expansion in tropical countries [7]. An assessment of the projected impacts of agricultural expansion on mammals is of utmost urgency to facilitate pre-emptive and effective conservation actions. Here, we estimate the impact of future scenarios of expanding agricultural land on the worlds terrestrial mammals. We couple fine-scale, speciesspecific suitability models for terrestrial mammals with fine-scale projections of land use according to four global scenarios of socio-economic development. We highlight the countries in which the largest global losses of mammal distributions are predicted to occur between 2000 and 2050 and those countries predicted to host the species most in need of protection during this period. We define these countries as the future hotspots of global mammal loss (using loss of habitat as a proxy for species decline and potential extinction), recognizing that these future losses are likely to add to (rather than replace) those in areas currently concentrating high numbers of threatened species [3]. 2. METHODS (a) Habitat suitability and land use change models We projected the habitat suitability models described by Rondinini et al. [8] for 5086 species of terrestrial mammals onto four scenarios of human develop (...truncated)