Crabs can only be caught using Lobster Traps. Using five of any bait and waiting anywhere between 1-3 days will yield a crab. Depending on the bait and trap's location, a Lobster Trap may yield crabs of different sizes.
A COTD fish may be caught during its respective event using a Catch-of-the-Day Bait. All fish caught using a Catch-of-the-Day Bait have a max perfect size of 150lb, but the bait's extra effect may allow the player to catch even bigger fish, causing them to be labeled "Massive". The maximum massive fish size is 186lb.
A bug involving the Shrimp Lure made players able to catch any kind of fish with a greatly higher size than perfect during the first hours after the fishing update was released. This bug had since been fixed.