For years the number of red squirrels was so low they were almost extinct - but now the reds are back on the rise.
You would often see squirrels in parks, woods and even in your back garden - but the red ones were rare.
Red squirrels have been under threat for years, battling against other animals for food and territory.
They've also faced the deadly pox virus.
Martin visited a red squirrel reserve in Formby to find out the reason for the rise.