They are an effective fishing vessel because, when powered by a skilled person, they hardly disturb the water or the fish, and they can be easily manoeuvred with one arm, while the other arm tends to the net; two coracles to a net. The coracle is propelled by means of a broad-bladed paddle, which traditionally varies in design between different rivers. It is used in a sculling action, the blade describing a figure-of-eight pattern in the water. The paddle is used towards the front of the coracle, pulling the boat forward, with the paddler facing in the direction of travel.