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bioRxiv · 10.1101/026336

Combining niche modelling, land use-change, and genetic information to assess the conservation status of Pouteria splendens populations in Central Chile

Narkis S Morales·Ignacio C Fernandez·Basilio A Carrasco·Cristina Orchard
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Abstract

BackgroundPouteria splendens (lucumo chileno) is an endemic shrub to the coastal areas of Central Chile classified as Endangered and Rare by the Chilean threatened species list, but as Lower Risk (LR) by IUCN. Based in historical records some authors have hypothesized that P. splendens originally formed a large metapopulation, but due to habitat loss and fragmentation these populations have been reduced to two main areas separated by 100 km, neither of both currently protected by the Chilean system of protected areas. Knowledge about this species is scarce and no studies have provided evidence to support the large metapopulation hypothesis. This gap of knowledge limits our availability to gauge the real urgency to conserve remaining P. splendens populations, which can generate tragic consequences in light of the increasing land-use change and climatic change that are facing these populations. In this study we combined niche modelling, land-use information, future climatic scenarios, and conservation genetics techniques, to test the hypothesis of a potential original large metapopulation, evaluate the role of land-use change in population decline, assess the threats this species may face in the future, and combine the generated information to re-assess its conservation status using the IUCN criteria.\n\nResultsOur results show that locations with P. splendens are fewer than described in the literature. Results from the niche modelling and genetic analyses support the hypothesis of an originally large metapopulation that was recently reduced and fragmented by anthropogenic land-use change. Future climate change could increase the range of suitable habitats for P. splendens towards inland areas; however the high level of fragmentation of these new areas is expected to preclude colonization processes.\n\nConclusionsBased on our results we recommend urgent actions towards the conservation of this species, including (1) re-evaluating its current IUCN conservation status and reclassifying it as Endangered (EN), and (2) take immediate actions to develop strategies that effectively protect the remaining populations.

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Narkis S Morales, Ignacio C Fernandez, Basilio A Carrasco, Cristina Orchard. 2015-09-08. Combining niche modelling, land use-change, and genetic information to assess the conservation status of Pouteria splendens populations in Central Chile. https://doi.org/10.1101/026336

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