I am an invertebrate biologist from New Jersey working primarily with insects and freshwater mussels. While conducting surveys at a Lake in Warren County I encountered a large (approx. 3.5" long) bright red Crayfish. It was extremely aggressive. I am no expert on Crayfish but fairly familiar with the few species currently documented in New Jersey. With only a mediocre photo taken with my phone I have done some research after a fashion. I have tentatively ID'd this as Procambarus clarkii. If there are any Crayfish experts reading this I would be grateful for your thoughts and insights. This species is not on any of our official list.