A new study has shown that while some native bird species in Israel are declining, non-native species are thriving in their place.
The study by the Israel Institute of Technology (Technion) showed that 75% of the most common bird species in Israel have been in decline for the past 15 years. House Sparrow has declined by 28%, while the White-spectacled Bulbul population has dropped by 45%.
"It is concerning that the species we grew up with are now declining," commented Technion Faculty of Architecture and Town Planning Professor Assaf Shwartz. "I am afraid that soon my children won't be able to see and hear and interact with the sparrow [and] the bulbul …which used to be very widespread across Israel."
Land use, particularly urbanisation, has pushed away many native species while favouring non-natives, which thrive in the new environmental conditions. For now, the negative trends for the native species have been mostly limited to human-dominated residential areas. But there are signs that the same effects may soon reach natural landscapes.
Mynas and parakeets are more aggressive than local bird species and outcompete them for food and other resources, Shwartz says in the study, which was published in the journal Biological Conservation.
The researchers warn that that the shift will lead to Israel’s bird communities becoming increasingly homogenised. They suggest appropriate management strategies to halt or mitigate the spread of non-native birds.
Colléony, A & Shwartz, A. 2019. When the winners are the losers: Invasive alien bird species outcompete the native winners in the biotic homogenization process. Biological Conservation, DOI: https://doi.org/10.1016/j.biocon.2019.108314