Control of invasive ring-necked parakeet (Psittacula krameri) in an island Biosphere Reserve (La Palma, Canary Islands): combining methods and social engagement

Abstract

The ring-necked parakeet (Psittacula krameri) has been naturalised in La Palma Island Biosphere Reserve since the late 1990s. Due to landowners' complaints about the impact of parakeets on crops, a control scheme was implemented to eliminate the known population, initially estimated at 70 birds. The programme finally comprised three different phases. Between December 2015 and September 2016, 107 parakeets were removed by trapping using 14 decoy traps. Due to inefficient handling and trap shyness developed by the parakeets, traps were removed from October 2016 to November 2017, with at least 20 parakeets remaining in the wild. The control measures restarted in December 2017; 34 parakeets were counted and 13 were trapped. Since the parakeets had started to breed, the method was changed from trapping to shooting, to remove the last 34 parakeets. In total, during the entire project (December 2015-May 2018), 175 ring-necked parakeets were managed: 154 removed from the environment, 1 handed over to the project staff, and 20 registered by authorities as pets. Considering the undetermined number of ring-necked parakeets kept as pets on the island, an early detection and rapid response system has been set up by the island council, engaging public workers and volunteers to investigate and control new escapes. This project is one of the few cases worldwide where naturalised breeding populations of this invasive species have been successfully eliminated from the environment. Negative effects on biodiversity and human interests were thus minimized, and especially important, this was achieved without generating any social conflict.

Economic costs of invasive alien species in Spain

“…However, it could be that our data are conservative regarding the real costs incurred in protected areas. For example, Saavedra and Medina (2020) showed that an eradication programme implemented in La Palma Island, Spain, prevented the expansion of the ring-necked parakeet (Psittacula krameri) into La Palma Island Biosphere. These costs were, however, recorded at the island level, not only in the protected lands.…”

Rescue data as an alternative for assessing trends and phenological changes in two invasive parakeet species

“…Amongst conservation scientists, global consensus highlights that alien species represent one of the main causes of the worldwide current biodiversity crisis (Blackburn et al 2019;Liu et al 2020;Pyšek et al 2020). Following a parsimony principle, all alien species may exert impacts on native ecosystems (Kumschick and Nentwig 2010;Blackburn et al 2014;Evans et al 2018), and these effects should be limited through addressed management actions (Hulme 2006;Mazzamuto et al 2020;Saavedra and Medina 2020), often involving high economic costs (Bacher et al 2018;Diagne et al 2020). Early detection and surveillance programs of new invasions (or newly invaded areas) by alien 1 3 in Mediterranean countries (e.g.…”

Dietary plasticity in an invasive species and implications for management: the case of the monk parakeet in a Mediterranean city

“…Nevertheless, we stress that social considerations should not prevent relevant governmental bodies from pursuing efforts to control the species. Recently, a management plan in the Canary Islands (Spain) successfully eradicated a small number of rose-ringed parakeet from La Palma island by combining trapping and shooting with social collaboration (Saavedra and Medina, 2020). We recommend, therefore, a multidisciplinary approach, combining various methods to remove the parakeets, and building as much social learning and trust as possible by promoting effective communication and education of the public (Crowley et al, 2019;Perry and Perry, 2008;Shackleton et al, 2019).…”