Chicago's Hyde Park neighborhood has long been a haven for the bright green monk parakeet, but its presence – and recent decline – is shrouded in mystery.
The birds, a type of parrot indigenous to South America, were first spotted in Chicago during the 1970s. It's widely believed they entered the U.S. via the exotic pet trade in the late 1960s.
How the monk parakeets ended up in Chicago is uncertain. Some theorize the birds escaped a shipment at O'Hare or that pet owners simply released them into the area. Equally unclear is why these resilient, colorful parrots, which have become symbolic of Hyde Park over the past 40 years, are leaving the neighborhood.
One explanation put forth is tied to the population of yet another bird.
In her 2015 article, "The missing birds of Hyde Park," University of Chicago alumnus Karen Bradley decried regional efforts to bolster the peregrine falcon population at the expense of other bird species.
"Hyde Park’s bird population has been utterly decimated by the purposeful release of peregrine falcons sometime around 1999 by the Minnesota Raptor Center, sadly in association with the Chicago Audubon Society, the Chicago Academy of Sciences, the Illinois Department of Natural Resources, and the Lincoln Park Zoo," she wrote in the article published in the school’s independent newspaper.
Stephen Pruett-Jones, an ecology professor at the University of Chicago, doesn't buy this theory. He's been observing the local monk parakeet population for two decades and published a study in 2011 titled “Urban parakeets in Northern Illinois: A 40-year perspective” in the journal Urban Ecosystem.
He doesn’t deny the fast-swooping raptors are preying on starlings and pigeons, which are numerous, but said it’s unlikely they’re making a noticeable dent on the local monk parakeet population. That’s partially because he knows of only one peregrine falcon pair in Hyde Park, located on University of Chicago’s campus. And even more so, parrots aren’t the falcon's favorite prey.
“Peregrines generally don’t like parrots,” Pruett-Jones said. “Unless the peregrine captures the parrot carefully, the parrot could bite the peregrine’s leg off.
“A monk parakeet’s bill is a powerful weapon. If you handled one, you couldn’t do so safely without some thick gloves.”
Pruett-Jones and his collaborators conducted multiple censuses of the species population in Hyde Park over more than 20 years. For the greater Chicago area, they used data from old news articles, additional censuses and asked local birders to send their observations.
Pruett-Jones' research shows that the population grew steadily through the 1980s and spiked in the early '90s. At least 17 monk parakeets were recorded in 1985 and Pruett-Jones personally counted 64 in 1992. Five years later, his census documented 208 of the birds in Hyde Park – a growth rate of about 23 percent each year.
The population remained “relatively stable” at 300 birds between 2002 and 2006, according to Pruett-Jones. After that period, a steep decline began: in 2008, Pruett-Jones and his team counted 84 monk parakeets in Hyde Park. But the birds didn't seem to be dying off – instead, they were relocating in increasing numbers. Monk parakeets were spotted in the southern and western suburbs and areas further north and west of Chicago.
The shift in location sharpened through the 2000s. Pruett-Jones’ 2010 survey shows an estimated 778 birds in the greater Chicago region, with just 10 percent in Hyde Park.
To the vexation of utility companies, monk parakeets like to build their typically large, communal nests on man-made structures in addition to trees. Utility poles and satellite dishes often serve this unintended purpose.
This practice gives way to another theory that utility providers are clearing out nests and inadvertently impacting the local population.
But Pruett-Jones says these companies are supposed to remove nests only if there is a power outage or risk of fire.
“Some of the birds have disappeared from areas where the cause could not have been removal of nests,” Pruett-Jones said. “I honestly don’t believe ComEd could in any way be responsible for the population decline.”
John Schoen, a spokesman for Commonwealth Edison, northern Illinois’ primary electric utility provider, said they receive about five to 10 calls a year regarding nests.
“We try not to destroy nests,” Schoen said. “We’ll remove them carefully and make sure that there aren’t any eggs or chicks in them.”
If there are fledglings or eggs, Schoen said they’ll try to work with the Greater Chicago Cage Bird Club to safely relocate the nest.
“I can’t say that it happens all the time,” Schoen said. “But we try. We’re not bird specialists.”
A national drop in numbers
The apparent decline is not just a local phenomenon.
The U.S. population of monk parakeets has mostly plummeted since 2004, after a period of steep growth, according to the National Audubon Society's Christmas Bird Counts (CBCs), annual, volunteer-driven censuses of birds throughout the Western Hemisphere.
The 2003 CBC counted 4,452 monk parakeets in the U.S. – the most since the species came here. In 2010, fewer than half that number were counted.
Nat Miller, director of conservation at Audubon Chicago Region, said the CBCs cover most of the same area each year. Therefore, the trend happening in Hyde Park could be taking place on a broader, national level for the non-native species.
Miller theorizes monk parakeets could be exceeding their carrying capacity in areas they've overpopulated. Carrying capacity is the maximum population size of a given species for it to survive in a certain environment indefinitely. If a species' food or water supply becomes limited in a certain area, it will move on.
"These birds thrive in large colonies," Miller said. "These colonies were building very fast, doubling or tripling in size year-to-year. If you have 800 parakeets in a neighborhood like Hyde Park, that's a lot of stress on bird feeders, plants and food availability in general, so they'll distribute into additional colonies somewhere else."
Miller pointed out that the parrots are an invasive species that rely on people and urban areas, at least in northern U.S. cities like Chicago.
"Because these birds are introduced, they're still invading new places," Miller said. "The dependence on humans plays a huge role. If we do things differently, that could have an impact on their carrying capacity for a certain area. Based on what plants we put out and what seed we make available in bird feeders, that's incredibly important for these species. That's something that can change quickly for these birds because humans change their behaviors."
Miller said whether the birds are moving away due to a strain on resources or direct threats is unclear. He said answers will come with time but that "these things happen on an evolutionary scale."
Pruett-Jones believes more expansive and longer-term censuses are necessary to know exactly what's going on. While he hasn’t formally surveyed the parrots' nests since 2012, he believes the monk parakeet population has declined significantly since his study was published.
“We don’t know why the numbers are going down and I don’t think anyone in the country knows why they are,” Pruett-Jones said. “It could be a disease that we’re unaware of, like West Nile virus, which has hit robins and blue jays pretty hard.”
But he said the parakeets’ tissue has not been sampled to detect any disease or abnormalities.
“I think it’s safest to say it’s a mystery,” he said. “I don’t believe it’s human-induced, but that it’s caused by some biological process that we haven’t figured out yet.”
The late Mayor Harold Washington, who lived across from Hyde Park's first monk parakeet colony, called them a "good luck talisman." After his death in 1987, residents rallied to protect the non-native species when the USDA threatened to remove them.
The birds stayed then, but their story isn't over.
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