A large number of Pelican and other water/sea birds fly around and on top of vessels crossing the canal in search of food.
A vessel must pay a toll fee to use the canal, which is calculated based on the size of the ship, type of ship and the number of passengers or the amount of cargo onboard. An astronomical amount for cruise ships.
Any consolation: it’s totally free for the birds and that includes food.
A Flying Pelican on the Panama Canal, MG_5937