Climate Change Helping Bats Move Across Europe
Climate change is the likely cause of the astonishing spread of Kuhl’s pipistrelle, a type of vesper bat, across Europe since the 1980s, according to a 2016 study by researchers at the University of Naples Federico II. The study, published in Springer’s journal, The Science of Nature, is the first to record such a large-scale range expansion for bats.
Researchers warn that even though the Kuhl’s pipistrelle can be seen as benefiting from the effects of climate change in this situation, they can compete with and endanger other bat populations in the areas that they colonize, having a negative effect on biodiversity.
Researchers chose to study the Kuhl’s pipistrelle because it is an adaptable bat that can survive in a variety of habitats including urban areas (they roost in buildings and feed at street lights). Its adaptability makes Kuhl’s pipistrelle an ideal subject to study how climate change and urbanization affect species distribution and how this may threaten biodiversity.
Kuhl’s pipistrelle was originally recorded in western Asia, North Africa and southern Europe. In southern Europe, it was initially found exclusively in the Mediterranean basin. Kuhl’s pipistrelle then spread north to the Alps and western France, east to the Balkans and west to the Iberian Peninsula. It was reported in Bulgaria and northern France by the 1980s.
In the last 40 years, Kuhl’s pipistrelle has colonized the United Kingdom, the Czech Republic, Slovakia, Ukraine, Hungary, Romania, Bulgaria, Serbia and Poland, expanding its geographical range by 394 percent.
Study supervisor Danilo Russo and colleagues collected 25,132 high-resolution occurrence records of Kuhl’s pipistrelle in Europe between 1980 and 2013. Researchers then used these records in conjunction with several models (using three bioclimatic variables and one proxy of urbanization) to predict whether the spread of the bats to new areas was due to climate change or increased urbanization or a combination of both.
According to the study, the spread of the Kuhl’s pipistrelle is largely due to climate change factors. In particular, warmer temperature during winter was the most important factor in predicting the presence and colonization of Kuhl’s pipistrelle. Average annual rainfall and seasonality of rainfall were also factors, but to a lesser extent (rainfall affects water and insect availability).
Even though urbanization has increased in many of the newly-colonized areas, it had little effect on predicting the presence of Kuhl’s pipistrelle.
"According to our work, the Kuhl's pipistrelle is a 'winner' in the context of climate change," said lead author L. Ancillotto. "Given its high ecological flexibility, it might be strong competition to other bats in the regions that it newly occupies, and have serious consequences on bat assemblages."
Photo by: Leonardoancillotto86, Wikimedia Commons