What does it mean to dream about a seagull?

Dreaming of a seagull has no particular meaning unless other elements in the dream give it some sort of significance. For example, if the gull in the dream spoke or brought you a letter or a gift of some sort, or, contrariwise, if the gull attacked you. In any of those examples, the meaning of the dream would lie in what happened and in the emotions you experienced while in the dream.