Man, that is horrible and a total disrespect of resources and others who enjoy/depend on them.
This is why learning about the food web/chain of ecosystems at a young age is so important; in addition to sound parenting with an emphasis on integrity.
You know, I can't help but feel like a fine would never be enough. I've heard stories of parents who caught their kids smoking and made them finish an entire pack as punishment. (Whether that helped or not is another story.)
I say, let the punishment fit the crime. I'm sure they had plans on eating them...
Eat up!!! One by one...daily until gone...while they percolate on that tarp! Sushi!!
This may sound mean, but if those fish could talk....they may agree.
"Life is shorter than we've been lead to believe. Soak it all up like a dry sponge!"
"If I never win anything else in life, I smile knowing I came in first place in a race of billions!"