Tahitian prawns were introduced to Hawaii back in the 1950s and are now found on all the islands thanks, in part, to the fact that their life cycle includes a stage in the open ocean. The prawns have become a popular food here though, as with most introduced species, there’s a downside. They prey on native species in the streams they inhabit.

One such stream runs through Hawai’i Tropical Bioreserve & Garden, which is where I saw these Tahitian prawns. This stream is also one of several on the island where the prawns have been virtually wiped out on occasion. That’s because, while it’s legal to catch these prawns, it’s not legal to do so by dumping insecticide in the stream. Not only does this kill all the prawns, but it wipes out pretty much everything else that’s alive in there. And then there’s the small matter that these prawns are harvested for human consumption. Would you like insecticide with that?

Catching people in the act has proved difficult, but last year authorities did apprehend one man who had killed 6,200 prawns using this method. Earlier this year, he was fined $633,840 for his actions and the hope is that the big fine will discourage others. Mind you, the perpetrator looked like someone who would have trouble raising $840, let alone the other $633,000.