If you're interested in adjusting your seafood eating habits towards eating more sustainable seafood, the Monterey Bay Aquarium maintains a guide on which seafood (based on species and location/method of catch) is most sustainable, somewhat sustainable, and not sustainable. My favorite version of the guide is the printable version that you can fold up and put in your wallet: https://www.seafoodwatch.org/seafood-recom…
I got to see Alton Brown talk about sustainable seafood there! His message was pretty much "Eat calamari, eat it a lot."
I have spearfished for over 30 years and it is astonishing how much the fish population has declined even in my lifetime.