Researching life among death: The monk parakeets that call Green-Wood Cemetery home

A group of green monk parakeets sits nestled at the top of Green-Wood Cemetery's 19th century gothic arched entrance.

However, there is a chance you can hear them before you seem them.

How vocal are these colorful birds? Just ask tourist Tim Ozog, who was visiting the Brooklyn cemetery with his wife Carol Summers.

“I have hearing aids, so, their particular screech is somewhat annoying," Ozog, who is from Seattle, said.

Eric Thompson, a researcher and grad student at Hunter College Animal Behavior and Conservation program, told NBC New York that indeed the birds are "very vocal" and "very loud."

Thompson has spent months studying the birds -- a species that is native to Argentina and Uruguay -- for his thesis. He says what most likely happened is that the birds arrived at the cemetery from the pet trade. Either escaping or being dropped off by pet owners who couldn't keep them.

“There’s a myth that they were in a container at JFK and it somehow broke or was opened accidentally and that’s how they got here," Thompson said.

Now, for the first time, there is research happening to figure out not how they got here, but why they've stayed.

"In the late nineties early 2000s when there was some restoration work going on in the Gothic arch there was an attempt to move the nest," Sarah Evans, Senior Manager and Curator of Living Collections at Green-Wood Cemetery told NBC New York. "After the restoration happened, the monk parakeets then started rebuilding their nest back.”

Thompson explained that the species is quite communal and live in groups.

“They’re just little green parrots. They’re communal. They live in huge nests that are sort of like apartment buildings where everybody has their own little house," Thompson said.

"They're one of the rare opportunities around here to study an animal that's not in a cage," he went on to say.

For a place so closely associated with death, there is a lot of life at Green-Wood Cemetery, so much so that some living things here aren't found anywhere else -- a revelation that has come to light thanks to a growing amount of research happening daily.

“Actually, a new fungi was just discovered here by a citizen scientist. That piqued the interest of scientists in Hungary," Evans said.

Visitors are encouraged to participate in discovering and documenting life at Green-Wood using apps, like iNaturalist.

With a soon-to-come education and learning welcome center set to open in 2025 and an ever-busy nest, this cemetery is as bustling as the city it's in.