Hunting and Fishing

Catching and releasing when fishing

Q: I went fishing recently and before catching any fish I did not have a clear intention whether I would catch and release the fish or eat it. When I had the fish already hooked on the line I was told that we should eat it by 1 person so I pulled it out and thought we were going to eat it. But then another person more knowledgeable told me to release it back into the ocean because the fish was a bottom feeder and would not be nice to eat. I then released the fish back into the ocean after it had already been hurt by the hook. I did not know that it is not good to catch and release before fishing. Did I commit a sin by catching and releasing that fish?

Using dead fish as bait and sport fishing

Q:

1. Are we allowed to use real dead fish as bait when fishing? Meaning, not the rubber bait, bait like sardines, etc. 

2. Are we also allowed to catch and release fish?

3. If 'no' for the above question, the law says that certain fish must be a certain length and they should not be endangered, etc. and if they don't meet those requirements they must be released, or else you can get fined if caught. So if the answer is 'no' for question 2 then what should we do. Will we be sinful if we release the fish once we caught it, because you don't really know what size fish and species you catching until you caught it.