Extinctions in Paradise? The impacts of climate change on endemic amphibians of the Seychelles Archipelago

Climate change is one of the main causes of biodiversity loss globally. Endemic and spatially restricted species are highly vulnerable to extinction. The biodiversity on small islands in particular is at a high risk due to restricted ranges. The Seychelles are a biodiversity hotspot with a high concentration of endemic species at risk, home to thirteen endemic amphibian species. Amphibians are rare on islands and these species have been isolated from their closest relatives for over 65 million years. Worldwide, amphibians are facing population declines with more that 40% of species at risk of extinction. Despite this, amphibians are relatively understudied in comparison to other taxa. Many of the amphibian species in the Seychelles have incredibly limited distributions and are habitat specialists. This includes frogs and caecilians (limbless amphibians). The caecilian species in particular appear to have very narrow elevational ranges, with one (Hypogeophis montanus) only found on one island between 718m and 731m above sea level. Species found at higher elevations can be at greater risk of extinction from climate change due to upward displacement leading to significant range reduction.
The project will aim to establish the impact of climate change on Seychelles amphibians, their distribution, and their adaptive potential to these changes. This will inform on the vulnerability of these endemic species to extinction and the potential for mitigation & conservation measures. Climatic data is limited in the Seychelles and unrepresentative of the large variation present. I will expand climate data measurements to fill an important gap in knowledge and establish a climatic baseline for a range of elevations and habitats. This will inform on climate change mitigation and allow for longer term monitoring into the future for the benefit of the Seychelles. I will establish the ranges of amphibian species using historical data and fieldwork. This can be combined with modelling to infer potential distribution shifts under future climatic conditions and establish suitable habitats. The adaptive potential of species will also be examined through genetic analysis of potential key biomarker genes with signatures of selection or stress response to environmental change.