Common Myna (Acridotheres tristis) in Cyprus: mapping spread, control methods and impacts on birds globally.

Abstract

The Common Myna (Acridotheres tristis) stands as one of the most important avian invaders on a global scale, its presence extending across diverse ecosystems and continents. With its range continually expanding, the Common Myna poses significant challenges to both biodiversity conservation efforts and human populations. Among the regions susceptible to the invasion of such avian species are the Mediterranean islands, including Cyprus, which has recently invaded from Common Myna since the early months of 2022. The primary objective of this study was to assess the distribution of Common Mynas across Cyprus, implement effective control measures, and conduct a literature review on the global impacts of Common Myna on bird species. This served as an early warning signal for potential negative consequences for indigenous bird species in Cyprus. Since the initial sighting of the Common Myna in Limassol in 2022, fieldwork has resulted in the documentation of 54 Common Myna records from 20 locations across Cyprus. Through field observations and data validation processes, 39 of these records have been confirmed, leading to the creation of a distribution map for Common Mynas in Cyprus. For the reduction of Common Myna population, a combination of control methods has been employed, including shooting and trapping. Notably, shooting has emerged as a primary method for reducing Common Myna numbers, with 15 individuals culled from various locations in Limassol by 08/03/2023. Successive shooting periods have yielded discernible reductions in Common Myna sightings, suggesting the potential efficacy of this approach when implemented intensively and widely. The effectiveness of decoy traps remains inconclusive and requires further investigation. Along with fieldwork, a literature review has been conducted, revealing negative impacted avian species by the Common Myna worldwide. Among the 65 species identified, varying degrees of impact were observed, encompassing negative, positive, and neutral effects. Notably, small and medium-sized bird species were most negatively impacted, highlighting the need for management strategies in order to save vulnerable populations. Also, most cavity nesting birds are negatively impacted by the presence of the Common Myna, primarily through competition for nesting sites (61%), followed by predation or aggression (35%), and a small percentage due to competition for food (4%). Furthermore, the IUCN status of affected birds was considered, revealing that a significant portion of negatively impacted species were classified as "Least Concern." However, several species classified as "Vulnerable," "Endangered," "Critically Endangered," and "Near Threatened" were also affected, highlighting the need for targeted management strategies to protect endangered species and mitigate the impact of Common Myna invasions. In conclusion, this study underscores the critical importance of continuous monitoring, public awareness, and proactive management strategies to mitigate the impacts of the Common Myna invasion in Cyprus. Through concerted efforts and interdisciplinary collaboration, it is hoped that Cyprus can effectively address the challenges posed by this avian invader, protecting its rich avifauna.