Could this have been a skua?

Observation - Could this have been a skua?. Description: There were two large sea birds, bigger than herring gulls which were bothering some terns, fishing off the beach at Lannacombe, South Devon. After a few fruitless minutes of chasing the terns, they landed on the sea and floated for a few minutes before fl

There were two large sea birds, bigger than herring gulls which were bothering some terns, fishing off the beach at Lannacombe, South Devon. After a few fruitless minutes of chasing the terns, they landed on the sea and floated for a few minutes before flying away. They were mid brown in colour with darker undersides and black edges and tips to the wings. Their behaviour suggested a skua but which one and were they migrating north? Didn't get a photo.