I took a ferry across Tokyo bay. There was a flock of seagulls trailing the ferry and many people were feeding them crisps. I tried it as well. They're incredibly accurate and quick. The moment I put out my hand the closest seagull would swoop in and snatch it out of my hand. It made almost no contact, though sometimes their feet would graze my hand.
This was a tricky photo at first, but easy once I knew what to do. The trick is to hold my hand out completely (towards the ground so no seagulls snatch the crisp) and prefocus. Then I switched to manual and locked the focus. I also turned up the ISO to 800, so that I had a fast shutter speed at f/5.6. The final piece of the puzzle was shooting at 11 fps, which was absolutely necessary to get the decisive moment.
It was really cold up on the ferry deck, but I couldn't stop it was so much fun playing with the seagulls!