Thousands of grey squirrels are being killed in the north of England to help protect their red relatives.
Traps have been set in Northumberland after experts decided they were threatening the red squirrels by taking their food and spreading disease.
About 15,000 greys have been killed over the past year in the area. Lots have been sold as meat in butchers.
Some organisations, like the RSPCA, think that culling is not the right way to deal with the problem.
As well as stealing their food, the bigger grey squirrels also carry diseases that can kill reds.
Greys came over from North America more than 100 years ago and have spread across England and some of Scotland. This has led to a huge drop in the number of red squirrels in the UK.