Micro-fishing is the latest craze in the fishing world. This has nothing to do with those films in the library that hold images of old newspaper. That’s microfiche.
Micro-fish are teeny tiny fish that can still be caught with a hook. Fishermen do this for the beauty of it, not because they provide a good meal, obviously. It’s like bird watching but for fishermen. They are seeking out tiny fish that are beautiful or interesting and they throw them back. It’s a peaceful pastime. For some.