Black buzzards are circling New York City in sightings that 'would have been unheard of' 30 years ago, ornithologists say

• Black vultures have been making their way north due to milder weather caused by climate change.
• Ornithologists in New York have recorded more than 300 sightings in the last year.

Climate change is behind the unusual appearance of hulking, bald-headed black vultures across parts of New York City, ornithologists say.

The vultures, which usually make their habitat in the southern states and across Mexico and other portions of Latin America, are now being seen regularly as far north as Manhattan.

The birds are changing their migratory patterns, being driven north by dwindling habitat space and milder winter weather, The New York Times reported.

Just 30 years ago, spotting groups — or committees — of black vultures so far north "would have been unheard of," Andrew Farnsworth, a researcher at Cornell University's Lab of Ornithology, told The New York Times. Yet, over the last year, the Cornell-backed public science project eBird has documented more than 300 sightings in the city.

Farnsworth told Insider the sightings are significant because, as the species expands its habitat in the region, the vulture's presence can impact relationships with other scavengers and omnivorous crows, as well as white tailed deer and other mammals that the birds eat, which as a result could impact how food chains in the region function or how diseases like West Nile Virus spread.

While the environmental impact of the vulture appearances remains unclear and will for some time, Farnsworth told Insider, it is likely to have impacts on other species, and those impacts can reveal information about the relationships between animals, changing climate, and epidemiology.

"All I do know is these huge creatures that have a wingspan of about five feet have invaded Staten Island," Deena Tomasulo, a resident of the Midland Beach neighborhood, told NBC News New York in August. "They perch on the roofs and stare at the animals — the feral cats, raccoons, and opossums. I have never witnessed an attack yet, thank God ... I just don't want any of the feral cats to get harmed, people have little small dogs. And if you put the dog in your yard, these birds will swoop in and attack."

Often regarded as an omen of death and renewal, the frightening-looking birds appear more intimidating than they are dangerous.

"They're not geared to killing, like a hawk or an owl would be, where they grasp and kill. They will come down and just eat mostly roadkill," said Don Riepe, with the Jamaica Bay American Littoral Society, a wildlife refuge, told CBS News. Representatives for the Littoral Society did not immediately respond to Insider's request for comment.

The new presence of the large birds may spell longer-term consequences for the ecosystem, The New York Times reported. Should the vultures disrupt the food chain or displace other birds by moving into the region, the impacts can ripple beyond just the sightings — potentially endangering entire species of insects and other animals by wiping out their food supply.

"All of our societies depend on these natural systems of insects, birds, plants in multiple ecosystems across the earth," Tod Winston, a researcher with the New York City Audubon Society told The New York Times, adding that environmental changes that impact birds should be a warning to us all, saying "people are in trouble," too.

The New York City Audubon Society did not immediately respond to Insider's request for comment.