I took my first nutria rat with a bow at about 16.

They are a nuisance down here (tear up levees and now you get paid to kill them in Louisiana).
They would all come to this one spot in a neighborhood pond at my buddy's house. We had
gotten in trouble for using a 22 in the neighborhood (with good reason), so we decided to shoot
them out of a second floor window with my bow. It was a blast, got about 6. They didn't know
what was going on due to the method utilized.

All other firsts were by gun.