Native to South America from Argentina to southern Brazil, Uruguay, Paraguay, and Bolivia, the Monk Parakeet now occurs in North America, Europe, Israel, and elsewhere due to its popularity as a pet ( Russello et al. 2008 ). In North America, free-flying Monk Parakeets were first noted in the late 1960s. Early on, it was feared that this parakeet would thrive in its new home, ravaging crops as its range expanded. Over the years, however, the threat of crop damage has not materialized. Despite their capacity to naturalize in a variety of places, the Monk Parakeet remains a popular species in the pet trade, accounting for 97% of all reported trade in parrots exported from South America between 2006–2012 ( Bush et al. 2014 ).
The Monk Parakeet is the only species in the parrot family that does not nest in a cavity. Instead, it constructs a bulky structure of sticks that can house a single nest or a complex with a dozen or more separate nest chambers. This behavior allows the Monk Parakeet to more readily adapt to landscape change than other parrot species, which often decline in response to logging, habitat loss, and the removal of suitable nest trees. The species uses and maintains its stick compound year-round, a behavior that may help to explain the ability of the Monk Parakeet to colonize areas with colder winters than in its region of origin.
Although crop damage in North America has not been a major problem to this point, the Monk Parakeet often build nests on electrical utility poles, transformers, and substations which can cause power outages and fires ( Avery et al. 2006 , Burgio et al. 2014 , Reed et al. 2014 ). Use of lethal methods to control Monk Parakeet populations and reduce damage, fires, and interruption in electrical service has been met with considerable resistance from the general public ( Russello et al. 2008 ) and has even led to a lawsuit against a utility provider in Connecticut, though the suit was ultimately dismissed. Although some non-lethal methods have been explored (such as chemical contraception, nest removal, and trapping), thus far, no practical, long-term solution has been developed.
In the United States, the species has a variety of common names, including Gray-headed or Gray-breasted Parakeet, Quaker Conure, and Quaker Parakeet. The bird’s cowl-like gray face and chest, reminiscent of religious attire, earned the species its Quaker and monk appellations.
The first review of this species’ distribution in North America ( Neidermyer and Hickey 1977 ) and several informative regional studies are available (e.g., Olivieri and Pearson 1992 , Hyman and Pruett-Jones 1995 , Pruett-Jones et al. 2012 ). Until the last decade, however, there had been relatively little research on North American Monk Parakeets; much of the information of their biology and life history remains based on work done in their native range (e.g., Martella and Bucher 1990 , Navarro et al. 1992a ). However, in the past 10 years, research on Monk Parakeet populations in North America has accelerated (e.g., Avery et al. 2012 , Davis et al. 2014b , Hobson et al. 2014a , Edelaar et al. 2015 ), with a great deal of research focusing on management (e.g., Avery et al. 2006 , Pruett-Jones et al. 2007 , Reed et al. 2014 , Burgio et al. 2014 ).