Source and sinks for Iberian butterflies detected

Mountains in the north and center of the Iberian peninsula are source of individuals, in the context of butterfly metapopulation dymanics, whereas the rest of the area, mostly the eastern coasts and Doñana, maintain sink populations.

The journal Insect Conservation and Diversity, one of several publications of the Royal Society of Entomology of London, has just published the article entitled “Identification of potential areas of origin and sinking of butterflies in the Iberian Peninsula” developed by the team of Biogeography, Diversity and Conservation, Department of Animal Biology, University of Malaga and with the collaboration of the Department of Biology, Autonomous University of Madrid. Whose authors are Dr. Ana Luz Márquez, Dr. Raimundo Real and the PhD student Antonio Pulido from the University of Malaga and Dr. Enrique García-Barros from the Autonomous University of Madrid.

The article highlights the usefulness of the Favorability function (F), developed in the Department of Animal Biology of the UMA by Dr. Real and team, to identify the dark biodiversity in general and, in this occasion, that of Iberian Lepidoptera in particular. Dark biodiversity refers, in this case, to the different condition in which a species can occur in the territory, which is in principle hidden from the observer’s eye. A species, in fact, can be present in a source area, with a higher birth rate than mortality and providing individuals that spread to other locations, or in a sink area, with higher mortality than birth rate and where the species is maintained because it receives migratory specimens from the source areas.

In this study, favorability models for the 222 butterfly species of the Iberian Peninsula have been established in terms of environmental variables (spatial, climatic, topographic, geological, and indicators of human activity). Using their respective presence-absence and favorability maps, we considered that a source zone is comparable to a high-favorability zone (F> 0.8) with a verified presence of the species, whereas a sink is equivalent to an area with confirmed presence of the species but with low environmental favourability (F <0.2). Given that the source territories are key for conserving the whole distribution area of the species, the possibility of distinguishing operationally between sources and sinks becomes a useful tool for the management of territories and species, in summary, for the conservation of biodiversity.

In this sense, the study shows that the principal source areas for Iberian butterflies are concentrated in the north and center of the peninsula, mainly in the large mountain ranges (Cantabrian Mountains, Pyrenees and Central System). On the other hand, the sink areas are more dispersed throughout the territory, with a singular concentration in the east and in the southwest area coinciding with the Doñana National Park.

This study is the result of the work carried out within the ongoing PhD thesis of Antonio Pulido, from which more results are expected soon.


Link to this news in the UMA website:

Link to the whole article in Insect Conservation and Diversity: