Hundreds of songbirds have died after crashing into glass skyscrapers in New York City.
The deaths of the migrating birds were highlighted on Twitter by Melissa Breyer, a volunteer from New York City Audubon which works to protect wild birds and their habitats in the area.
Ms Breyer discovered 226 dead birds in the area around the new World Trade Center towers and showed how the area was littered with bird carcasses.
The volunteer said she found the discovery “overwhelming” and “the sidewalks were literally covered with birds”.
Although the problem is not a new one, the number of fatalities seen this week were particularly high, with stormy weather contributing to the problem, the group said.
New York City Audubon has been documenting the issue for years.
Kaitlyn Parkins, the group’s director of conservation and science, said that a big storm along with “weird weather and lots of birds” created the “perfect combination” for bird-window collisions on Monday night.
“It seems that the storm might have brought the birds in lower than they would have otherwise have been, or just disoriented them,” Ms Parkins added.
“The effects of nocturnal light on birds is also quite strong, especially when it’s a cloudy night.”
The group has called on the owners of the large skyscrapers and other buildings to reduce the number of bird strikes by dimming lights at night and treating glass to make it more visible, to help birds recognise it as a “solid barrier”.
A total of 77 birds were taken to the Wild Bird Fund’s rehab facility on the Upper West Side on Tuesday, with the centre’s director saying the majority of them were from the trade centre area.
Staff gave the birds food, fluids and anti-inflammatory medications to reduce swelling and 30 of the recovered birds were released in Brooklyn’s Prospect Park the next day.
A spokesperson for the Durst Organization, a co-developer of One World Trade Center said the design of the building was chosen because it “greatly reduces bird strikes which mostly occur below 200 feet and are frequently caused by reflective glass”.
A spokesperson for Silverstein Properties, the developer of three other trade centre buildings, said: “We care deeply for wild birds and protecting their habitat in the five boroughs.
“We are actively encouraging our office tenants to turn off their lights at night and lower their blinds wherever possible, especially during the migratory season.”