The RSPCA in Swansea says it is seeing an increase in the number of abandoned cats and kittens it's taking in.
Staff there described this year as the 'worst ever' for the problem and said they're struggling to cope.
The problem stems from cat owners being caught out when their un-neutered pets have litters.
Now the society is working with Cardiff University to try to establish why owners aren't taking preventative measures.
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Stars of Team GB at this years' Olympics were in Wales today, as part of ITV's I Am Team GB campaign.
As Wales gets involved in the country's biggest sports day - Our Olympians have been getting in on the action.
ITV switched off all of its channels for an hour on Saturday as part of a national sports day event.