The animal welfare charity says that despite many months of lockdown, it has received more than 10 calls a day about animals being injured or affected by dumped rubbish.
These include a duck tangled in a medical face mask, a baby hedgehog with plastic wrapped around her neck, a fox with his head caught in an old Cornish pasty wrapper and a gannet entangled in plastic.
In Derbyshire, the charity’s inspectors have responded to 52 calls during this period, including a barn owl which was found tangled in a fishing line on the River Derwent.
The RSPCA is urging people to help protect animals by picking up any litter they see lying around as well as ensuring they take their own litter home with them.
Head of the RSPCA’s wildlife department Adam Grogan said: “Our staff deal with thousands of incidents every year where animals have been impacted by litter - and they’re the ones that we know of.
"I’m sure for every animal we’re able to help there are many that go unseen, unreported and may even lose their lives.
“Litter is one of the biggest hazards our wildlife faces today and the pandemic has just added to the problem with many disposable masks just being discarded on the ground.
"These are a new danger to animals and we’ve been called out to rescue animals like ducks and gulls caught up in the masks’ elastic straps. That’s why we’re calling on the public to get involved in the Great British Spring Clean to help remove litter that may endanger animals.”
As well as everyday rubbish, the RSPCA also sees many animals arriving into its care with injuries caused by angling litter.
Last month, the charity revealed a poor barn owl had been discovered ‘hanging helpless from a tree’ at Allestree Park after getting caught in a discarded fishing line.
Adam added: “Animals who get their heads or necks stuck in litter can suffer severe injuries as they struggle to break free and can even suffocate, while others will slowly grow weaker and weaker as they try to hunt or find food or water."