Lionfish are an invasive species apparently.  This guy makes a good case for killing them all.   I like the method:

From the description:

Shooting invasive Lionfish over 100ft underwater with customized Glock 9mm handgun in the Gulf of Mexico. The project started to see if we could shoot a gun underwater and it evolved into much more with the right people involved. Lionfish are an invasive species that need to be eradicated.

I’m positive there are easier ways to kill Lionfish (like a spear obviously), but spears just aren’t as cool as Glocks.  Sorry not sorry.

You can tell he hates the Lionfish so much by the way he disrespects it after he kills it.  Toying with it then even shooting it again sometime just for finesse.

The same guy put up another video explaining the modifications they had to do to the Glock, if you want to check it out. Thoughts?

Gat tip: Steve, Adamar