Jason South of Borneo Chela here, pitching in while your regular host braves the verdant jungles of Costa Rica.Here is the first of two posts on Monk Parakeets (Myiopsitta monachus), an introduced parrot that has established several breeding populations in the United States.
Many invasive species are subject to human disdain, or at least indifference, because they are a diminutive weed or foul, slimy thing that chokes up pleasant ecosystems with a bland uniformity. However, some nonnative species have been intentionally or unintentionally released in to the environment due to their cultural significance (i.e. beauty, popularity as companions). The ubiquitous house sparrow (Passer domesticus) and common starling (Sturnus vulgaris) are archetypal; both were intentionally released in to the US on several different occasions by English immigrants to provide a constant reminder of home (one particular individual wanted to populate the US with the birds mentioned by Shakespeare!). Over the past 30 years, more than a dozen parrot species have escaped or been released in to the wild in the US. The most numerous by far, in terms of both geographic locations and numbers of individuals, is the monk parakeet. This medium-sized parrot is native to the temperate grasslands of Argentina, Paraguay, Uruguay, and southern Brazil, and is common throughout its range. THe planting of eucalyptus has allowed the monk parakeet to expand its range in the pampas region of Argentina, due to increased availability of nesting substrates. Thousands of these parrots were imported into the United States in the late '60's and early 70's to be sold as pets under the name "Quaker parakeet". Shortly thereafter, the first free-flying populations began appearing, mostly near dense population centers such as Chicago and New York City. As of 2001, monk parakeets had been recently recorded nesting in 14 states across the country. Texas and Florida harbor the largest breeding populations. Population estimates are not available, but thousands of monk parakeets are likely flying free in Austin and the east coast of Texas, and throughout South Florida (especially Miami-Dade county and the Sarasota area). The parakeets in Florida have actually been counted, but the data have not been published because of fears that the state or federal government might seek to control the population (more on that in part II). A few dozen are nesting in Brooklyn, NY, especially on the stadium lights of a particular high school. The population I studied in Hyde Park, Chicago (location of the University of Chicago) contained between 200 and 300 birds in Spring 2000 by my own count, with several dozen more nesting throughout the city and suburbs. How did so many parakeets make their way in to the wild? A combination of accidental escapes and intentional release. The story in New York, perhaps apocryphal, is that a crate containing monk parakeets fell and broke open at JFK airport in the early 1970's. The story in Chicago is even less clear, but newspaper articles suggest that the birds were first widely noticed in 1971, and were confirmed as breeding in 1979. These parakeets, and others around the country, were probably intentionally released by frustrated owners. Monk parakeet are incredibly friendly, gregarious, and easy to tame, but also ear-splittingly loud. They can be heard, even if far out of sight, all over Hyde Park as they call to each other in flight. How do they survive in the wild? The mild subtropical climates of Texas and Florida are a welcoming environment, but what about the harsh winds and winters of Chicago? Nests and birdseed are the likely answers. Monk Parakeets are the only parrots to build a nest that they use all year round for roosting. A pair will chew off hundreds of twigs that are then woven into a closed chamber with a single opening...once one of these chambers is built, other pairs will build their chambers on to the first one, thus creating a large social complex. A few birds huddled together in a chamber surrounded by other birds and chambers are likely to be warmer than a birds roosting on a naked branch. Monks also have a voracious appetite for bird seed, and will sit at feeders for hours in Chicago when it is cold outside (this supplemental feeding might limit their range in the northern states, however).