All seagulls drink seawater, and bird kidneys are not as efficient as mammals, so too much salt is more toxic to humans than humans.
The specialized glands near the eye sockets of the seagull can handle excess salt in the body. These glands look like small kidney detoxification organs. They work similarly. They use osmosis to drain salt ions out of the blood. The excess salt water will be on both sides of the bird’s nest. Drop it down.