U.S. Department of Agriculture: Animal and Plant Health Inspection Service


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Avery, M.L. and Feare, C.J. (2020) Control or eradication: problems in the management of invasive birds. In: Downs, C. T. and Hart, L.A. (eds) Invasive Birds: Global Trends and Impacts. CAB International, Wallingford,UK, pp. 349-361.


US gov't work


Humans have captured, transported and intentionally released wild birds for centuries (Blackburn et al., 2009). Motivations for such purposeful introductions include food (West and Zhou, 2007), religion (Agoramoorthy and Hsu, 2007), sport (McDowall, 1994), biocontrol (Bennett and Hughes, 1959; Kurdila, 1995) and aesthetics (Ryan, 1906; Thomson, 1922). Many purposeful bird introductions were the work of acclimatization societies, particularly in North America, New Zealand and Australia. These societies were formed in the 19th century by European settlers to transport bird species from their homelands in efforts to establish them in the newly settled regions (Thomson, 1922; Dunlap, 1997). As a result of these efforts, the Common or European Starling (Sturnus vuigaris), the House Sparrow (Passer domesticus) and many other species are now permanently established far beyond their native ranges.

Commercial trade in captive birds is also an important introduction pathway. Non-native species are introduced through unintentional releases of cage birds and inadvertent escapes from research facilities, zoos and private collections. The international bird trade has declined gradually following adoption in the USA of the 1992 Wild Bird Conservation Act and similar European regulations restricting trade in wild birds following the westward spread from China of the highly pathogenic H5Nl avian influenza virus in the early 2000s (Cooney and Jepson, 2006). The pattern of trade in wild birds has also changed. Mexico and Asia have replaced the USA and the European Union as the principal importers in the global cage-bird market (Cardador et al., 2017; Hobson et al., 2017). Nevertheless, large-scale traffic in wild and captive-bred birds continues. During the 3-year period 2000-2002, global ~orts of live birds totalled 3,640,135 compared with 807,476 during 2015-2017 according to the Convention on International Trade in Endangered Species (GTES, 2018).

Invasive birds have major impacts throughout the world, regardless of the invasion pathway. Pimentel et al. {2001) examined the published data available on invasive species in the USA, the UK, Australia, South Africa, India and Brazil. They concluded that introduced birds were responsible for US$2.4 billion in damage to agriculture, human health and natural resources among these six countries.

We focus in this chapter on a subset of these impacts, namely the threats that invasive birds pose to native species and the efforts that have been made to reduce or eradicate such impacts. Specifically, we review management options and control strategies, explore what has and has not been effective, and discuss case histories of success and failure.