In the TV series, Strawberry is a lazy rabbit after leaving with Hazel and the others from the Warren of the Shining Wires, since he likes to sleep in the burrow a lot. But later he becomes dependable after realizing that he wasn't being very helpful towards the Watership Down rabbits.
In season 3, Strawberry's color has changed to dark-pink and he has a much larger role. He has joined Bigwig's Owsla and is a skilled fighter and digger. He eventually becomes stuck under a tree during a training excerise, and is freed by Dandelion and Hawkbit. After Fiver has a vision of Hawkbit being killed, Strawberry is ordered by Bigwig to keep him in the warren at all times, pinning him to the ground and even fighting Hawkbit at one point. In The Magic, he is seen fighting several of the Darkhaven Owsla, and in the Watership Down warren when the storm takes away General Woundwort and his Darkhaven army.
Strawberry will appear in the upcoming miniseries of Watership Down.