Bird researchers in Arizona try to find out why owls are falling from the sky

PHOENIX (NBC, KYMA) - 54 owls are falling from the sky in the Arizona desert, and bird researchers are trying to find out why.

John Bello was just starting work at Deer Valley Petroglyph Preserve when he found an owl near a patio.

"I looked down in between the crack and the sidewalk and noticed that there was an owl down there. Not normal," Bello shared.

Bello contacted a bird researcher who told him to put the deceased owl on ice. The researcher knew something strange was happening.

Bello's discovery was one of 54 flammulated owls found in the Phoenix area last year between September and October, all brought to Valley Bird Rescues.

That's compared to just nine owls of the same species turned in the previous year and three more before that.

"We are exploring a mortality event that occurred with flammulated owls, which are a small m'igratory insectivore owl," said Jason Struthers, veterinary pathologist at Midwestern University in Glendale.

Struthers is trying to figure out what happened.

13 of the owls were rehabbed. The carcasses of the other 41 are now under the microscope being studied at midwestern and two other colleges.

"We open the carcass and look at all the organs. to look at types of poinsons they might be exposed to. we try to cover all our bases by sampling all of their organs,"

Struthers has one big clue: A fall heat wave last year overlapped with the owl discoveries.

"The temperatures were around 2.4 degrees Fahrenheit greater this past year than the year prior, 39 of the 41 is that they have damage to the kidneys that could be a concern that they're experiencing dehydration," Struthers argued.

After all tests are complete if heat remains the most likely cause, it will demonstrate how even small changes in temperature can have debilitating effects on this species.

"We hope to really paint a picture and whether this will be a repeating issue that will be more common as the Sonoran Desert temperatures continue to increase," Struthers remarked.

A migration mystery, with an answer likely in reach, and it's thanks to people across the valley, like Bello, who cared enough to take a moment out of their day to act.

"There's a term that's used for that called citizen science or citizen scientists. you still can play the role of a scientist by providing little bits of data that other scientists can use to better understand a species, better understand an environment," Struthers explained.

"I think it's really important that we have that natural wonder and curiosity, especially when it comes with nature, we're all here together to try to survive and thrive in this desert environment," Bello added.