To Cyprus for the sea? Why not for the bats?

To study the bats in Cyprus, we used their method of communication – echolocation. This involves emitting sounds with specific characteristics, such as frequency, intensity, strength, or interval. The ultrasound is then detected and, based on its rebound from an obstacle, the bat knows how far away it is and also what kind of obstacle it is – food or a flight barrier? These acoustic signals were detected and recorded as part of this study. Stationary sound detectors were located at sites attractive to bats, such as entrances to underground spaces or small water reservoirs. Transects using mobile sound detectors were situated in both urbanised areas and agricultural or natural landscapes. These two types of detection supplemented each other not only spatially but also temporally as the study was conducted in three different seasons. 

Eptesicus serotinus, source:File:Eptesicus serotinus.jpg - Wikimedia Commons

In total, 4 611 echolocation calls were recorded, which belonged to six species and came from 20 different habitats. With regard to the studied environs, transitional woodland-shrub was the one used by all the species, while in urbanised habitats, discontinuous urban fabric was preferred the most. 

What does the research imply about these species? Pipistrellus kuhlii was detected in all the studied habitats and was also the most commonly recorded species. It occurs in forested, seminatural, and agricultural habitats, including densely populated areas. Its food is diverse, which is associated with the number of habitats in which it lives. Eptecius serotoninus and Hypsugo savii were most often detected in agricultural habitats, but were also present in urban areas. One factor all bat species have in common is that there are fewer food opportunities on the Mediterranean islands compared with the mainland and therefore they often have to vary their food preferences. 

Overall, we can not only study the variability of species but also the different use of habitats, which we can further compare with data from the mainland. Acoustic studies are efficient when exploring long-term trends in bat populations which, because of the possible threat to biodiversity and the decrease in expansion of these mammals on the limited area of the Mediterranean islands, is now gaining in urgency. This type of monitoring should be used more often as the method could be standardised in the future. This would enable us to make comparisons across biotopes, studies, and time.

Eliška Leštinová

Uhrin M, Satterfield L, Kaňuch P, Benda P (2021). Habitat use and seasonal activity of bats on a large eastern Mediterranean island: Insights from acoustic surveys (Mammalia: Chiroptera). Zoology in the Middle East, 67(4), 290–301.