Received: 9 October 2019 | Revised: 17 January 2020 | Accepted: 4 February 2020 DOI: 10.1111/ddi.13047 BIODIVERSITY RESEARCH Combining geostatistical and biotic interaction model to predict amphibian refuges under crayfish invasion across dendritic stream networks Mário Mota-Ferreira1,2 | Pedro Beja1,2 1EDP Biodiversity Chair, CIBIO/InBio, Centro de Investigação em Biodiversidade e Abstract Recursos Genéticos, Universidade do Porto, Aim: Biological invasions are pervasive in freshwater ecosystems, often causing na- Vila do Conde, Portugal tive species to contract into areas that remain largely free from invasive species im- 2CIBIO/InBio, Centro de Investigação em Biodiversidade e Recursos Genéticos, pacts. Predicting the location of such ecological refuges is challenging, because they Instituto Superior de Agronomia, are shaped by the habitat requirements of native and invasive species, their biotic Universidade de Lisboa, Lisboa, Portugal interactions, and the spatial and temporal invasion patterns. Here, we investigated Correspondence the spatial distribution and environmental drivers of refuges from invasion in river Mário Mota-Ferreira, EDP Biodiversity Chair, CIBIO/InBio, Centro de Investigação systems, by considering biotic interactions in geostatistical models accounting for em Biodiversidade e Recursos Genéticos, stream network topology. We focused on Mediterranean amphibians negatively im- Universidade do Porto, Campus de Vairão, Vila do Conde, Portugal. pacted by the invasive crayfishes Procambarus clarkii and Pacifastacus leniusculus. Email:
[email protected] Location: River Sabor, NE Portugal. Funding information Methods: We surveyed amphibians at 168 200-m stream stretches in 2015. Fundação para a Ciência e a Tecnologia, Geostatistical models were used to relate the probabilities of occurrence of each Grant/Award Number: SFRH/ BD/95202/2013; EDP Biodiversity Chair species to environmental and biotic variables, while controlling for linear (Euclidean) and hydrologic spatial dependencies.