Mystery As Hundreds of Paralyzed Parrots Drop From the Sky

More than 200 parrots fell from the sky over the past week, leaving scientists mystified.

The rainbow lorikeets dropped from the heavens above New South Wales in Australia, after which the fallen birds were rescued and taken to wildlife care facilities.

The colorful parrots were found to be suffering from the mysterious illness lorikeet paralysis syndrome (LPS), the cause of which is unclear to scientists.

LPS, as the name suggests, causes the birds to become paralyzed, falling from the skies as they lose the ability to fly. The cause of the disease is unknown, with researchers having been unable to find a pathogen or environmental toxin responsible, according to the University of Sydney.

It seems to affect the birds only in the Australian summer months, between October and June, with the highest numbers being impacted in the months of December, January, and February. During this period, thousands of the birds are taken into care to be nursed back to health, which may be an intensive and long-term process.

The disease was first identified in 2010, and appears to only affect birds between the towns of Bundaberg in Queensland and Grafton in New South Wales, 425 miles to the south.

"We have recognized the disease we call lorikeet paralysis syndrome from at least 2010, but it is likely that it was occurring before that," David Phalen, a professor of wildlife health and conservation at the University of Sydney, who works on the Lorikeet Paralysis Syndrome Project, told Newsweek. "There is even a tidbit of information that pathologists at the University of Queensland were seeing lorikeets that died with similar signs back in the late 1980s but I have not been able to track this down yet.

"LPS is a disease of the neuromuscular system and likely is caused by something that interferes with the nerve connections with the voluntary [skeletal] muscles, causing lorikeets to be paralysed. Most birds with LPS will recover (60 to 95 percent depending on the severity of the disease at presentation) if provided with proper veterinary care and high quality rehabilitation."

It was thought at first that the disease might be arising due to eating too many mangoes and getting drunk from the fermenting sugars in the fruit and its skin. However, the birds have been tested and found to have no traces of alcohol in their systems.

Scientists are also considering the condition may be triggered by something sprayed upon the fruit. All current tests for pesticides and fungicides on the fruits have found nothing, however.

"We have done considerable testing for toxins that lorikeets could be exposed to and would interfere with the nervous system and its connections with the skeletal muscles," Phalen said. "So far we have not found one in samples collected from lorikeets with LPS. However, there are many many toxins, natural and those released into the environment by humans that could cause LPS. These are the current focus of our research to see if we can identify a naturally occurring toxin or one of human origin that could be causing LPS."

Other theories suggest that the disease is caused by a toxin formed within a type of fruit as it ripens only during this specific period of the year,

To further investigate if this is the case, the Lorikeet Paralysis Syndrome Project researchers want the public to report back to them what they observe the birds feeding on in the wild, in case they have found new food sources in the aftermath of extreme weather events or other triggers.

Even more intriguingly, LPS appears to be related to other mysterious conditions in non-bird species like flying foxes, also known as fruit bats.

"There is another syndrome that also occurs in the same hotspots that most of the LPS cases come from and during the same time of the year and that is called Flying-fox Paralysis Syndrome," Phalen said. "The signs in the flying-foxes are essentially identical to those we see in the lorikeets with LPS and it is my working hypothesis that the cause of both LPS and FFPS is the same thing."

Update 2/5/24, 1:19 p.m. ET: This article was updated with comment from David Phalen.

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