SparkNotes: The Seagull: Important Quotations Explained, page 3

Idea for a short story. The shore of a lake, a young girl who's spent her whole life beside it, a girl like you She loves the lake the way a seagull does, and she's happy and free as a seagull. Then a man comes along, sees her, and ruins her life because he has nothing better to do. Destroys her like this seagull here.

Trigorin describes his idea for a short story to Nina in Act Two. He metaphorically compares Nina to the seagull Treplev shot in the same act. With this blatant use of Nina's life for his story's protagonist, Trigorin exhibits his ability to take advantage of the lives around him for his own purposes. Trigorin made a successful career out of adapting what he witnesses around him into fictionalized accounts. He openly uses Nina and promises to continue to use her and then throw her away when he no longer needs her anymore. This is exactly what he ends up doing. This quotation reveals Trigorin's nature as a parasite of the lives around him, yet he is not a villain because his actions are not devious. Trigorin openly admits to his plan for Nina and stays true to his selfish desires.