The charity has received more than 600 reports about animals found severely injured, trapped, mutilated, choked or even dead because of carelessly discarded litter over the past four years.
In Powys the charity confirmed has been called out to 17 cases of animals being seriously injured by litter.
One incident saw an RSPCA Cymru rope rescue team rescue a raven entangled in baling twine.
The raven had become entangled in the twine which was stuck on a nest on a 60 metre cliff in a remote area above Staylittle near Llanbrynmair, Powys.
This required the rescue team to abseil down the cliff to “a small ledge to cut free the entangled raven – as soon as he cut the twine the bird flew and went into a pine tree unharmed.”
The data – released today by the charity – also reveals that the figure rises to 12,817 across England and Wales (614 specifically in Wales).
In addition on average there were 13 reports per day made across England and Wales last year during the peak months of May, June, July and August, when there is a particular litter hazard for animals.
Today RSPCA Cymru is urging people to help “create a better world for every animal” by getting involved in Keep Wales Tidy’s Spring Clean Cymru (from 15-31 March).
Individuals, groups or schools can pledge their support – and say how many bags of litter they intend to pick up – with more than 400,000 collected in total last year.
RSPCA anti-litter campaigns manager Carrie Stones said: “Our rescuers deal with thousands of avoidable incidents every year where animals have been impacted by litter – including hundreds in Wales.
“Old drinks cans and bottles, plastic items and even disposable vapes are just some of the items that pose a danger to our wildlife – including hedgehogs, deer and foxes. Animals can ingest the litter or become entangled, leading to injuries, mutilations and even death.
“Sadly, for every animal we’re able to help there are probably many others that go unseen, unreported and may even lose their lives.
“But the public can help us protect animals, and avoid these incidents happening in the first place.”