Interestingly, it is not always the case that birds can drop what they catch. I never knew this until I watched an eagle struggle to shore after it caught a fish that turned out to be too large for it to fly off with or do what it needed to do to be able to release the fish until it got to land. I have no idea about the swimming ability of an eagle but they certainly can't swim when they have a large fish in their claws, it was quite the struggle for that eagle to get to shore.

https://www.raptorresource.org/2021/01/22/racheting-raptor-t...