That's a great collection of invasion methods, didn't know many of them before other than people in Florida buying then releasing pets like snakes or in this case lionfish. (a side effect is that the snakes are apparently overhunted in their native homes even if they're all over Florida...)

But I gave no thought to canals and ballast tanks greatly expediting the invasion process and wow as humans make it easier to connect with each other, they make it easier for animals to do so, too...

Lionfish really are quite well protected, casual fishers probably also don't want to mess with them too much (humans are lazy after all.)