Climate Change and the Distribution of Neotropical Red-Bellied Toads (Melanophryniscus, Anura, Amphibia): How to Prioritize Species and Populations?

Abstract

We used species distribution modeling to investigate the potential effects of climate change on 24 species of Neotropical anurans of the genus Melanophryniscus. These toads are small, have limited mobility, and a high percentage are endangered or present restricted geographical distributions. We looked at the changes in the size of suitable climatic regions and in the numbers of known occurrence sites within the distribution limits of all species. We used the MaxEnt algorithm to project current and future suitable climatic areas (a consensus of IPCC scenarios A2a and B2a for 2020 and 2080) for each species. 40% of the species may lose over 50% of their potential distribution area by 2080, whereas 28% of species may lose less than 10%. Four species had over 40% of the currently known occurrence sites outside the predicted 2080 areas. The effect of climate change (decrease in climatic suitable areas) did not differ according to the present distribution area, major habitat type or phylogenetic group of the studied species. We used the estimated decrease in specific suitable climatic range to set a conservation priority rank for Melanophryniscus species. Four species were set to high conservation priority: M. montevidensis, (100% of its original suitable range and all known occurrence points potentially lost by 2080), M. sp.2, M. cambaraensis, and M. tumifrons. Three species (M. spectabilis, M. stelzneri, and M. sp.3) were set between high to intermediate priority (more than 60% decrease in area predicted by 2080); nine species were ranked as intermediate priority, while eight species were ranked as low conservation priority. We suggest that monitoring and conservation actions should be focused primarily on those species and populations that are likely to lose the largest area of suitable climate and the largest number of known populations in the short-term.

Climate and land-use changes effects on the distribution of a regional endemism: Melanophryniscus sanmartini (Amphibia, Bufonidae)

“…In contrast with previous models for M. sanmartini (Zank et al, 2014), our model suggests an expansion in distribution range by mid-century under the IPCC scenarios considered (A2 and B2). Our predictions agree with the recently reported effect of climate change on the amphibians of Uruguay (Toranza et al, 2012).…”

“…The potential distribution of M. sanmartini predicted here is far smaller, about half of the modelled distribution proposed by Zank et al (2014). Aside from the use of different AOGCM and sets of climatic variables (see Zank et al, 2014), there is a key factor determining such a difference between both modelling studies.…”

“…Aside from the use of different AOGCM and sets of climatic variables (see Zank et al, 2014), there is a key factor determining such a difference between both modelling studies. The validation procedure applied here contributes to avoid commission errors, and thus allows us to get a distribution more similar to the 'realized distribution' of the species (Pineda & Lobo, 2009).…”

“…Although climate change constitutes a general threat to amphibians (Pounds, 2001), the 'tropicalization' of the transition zone between subtropical and temperate regions of southeastern South America, predicted for the mid21st century could favor the geographical expansion of amphibians (Lawler et al, 2009;Toranza et al, 2012). Nonetheless, for M. sanmartini a substantial contraction in its geographical distribution was recently predicted by Zank et al (2014). This scenario could be more critical to the viability of the species if LULCC was incorporated into the analysis.…”

A new record for Melanophryniscus moreirae (Miranda-Ribeiro, 1920) (Amphibia, Anura, Bufonidae) in the state of Minas Gerais, Brazil

“…Melanophryniscus moreirae (Miranda-Ribeiro, 1920) inhabits open, high-altitude areas of the Itatiaia National Park, between the states of Minas Gerais and Rio de Janeiro (Bokermann 1967, Guix et al 1998, Carvajalino-Fernández et al 2013 as well as high areas in the municipalities of Aiuruoca, Minas Gerais (Weber et al 2007), and Queluz and Campos do Jordão, São Paulo state (Figure 1) (Marques 2006, Zank et al 2014.…”