Dr White said: “Invasions by non-native species are considered a major threat to biodiversity, agriculture and sometimes human health. Ring-necked Parakeets in Europe originate predominantly from India and Pakistan. They are clearly very successful invaders and although serious impacts are currently unknown, the enduring, strong growth of their populations raises concerns.
“In Israel, Ring-necked Parakeets are culled because of alleged damage to sunflower crops, date palm and almond trees while in Spain, it is no longer legal to breed these parakeets as pets, to reduce the risk of escapees.
“Since the early 1970s, at least 90 Ring-necked Parakeet populations have established in 10 European countries and most of these populations are growing exponentially. It is, therefore, important to keep track of this avian invader.
“Ring-necked Parakeets gather at communal roost sites to spend the night, and thousands of parakeets can gather at such sites. Roost counts consequently are an excellent place to conduct population counts. Yet, because of ongoing range expansion, it becomes harder and harder to locate all roost sites and to find sufficient volunteers to conduct such roost counts.”