The distressed wild pigeon was found in the grounds of Beeston St Luke's C of E Primary School by a teacher, who removed the lid.
The new rules that could see you fined £100 for littering in LeedsWildlife charities regularly warn the public of the dangers litter can pose to animals.
Discarded fishing tackle regularly causes injuries to wild birds, while bottles and tin cans can also trap animals. Chinese lanterns, which are released into the sky, are notoriously dangerous to wildlife.
In 2017. a seal had to be rescued by experts after getting a frisbee-style dog toy trapped around his neck on a Yorkshire beach.