I brought some urchins and crabs with me from Hawaii to Chicago in my carry on baggage. However, you need to check with the airlines and see if they are allowing carry on baggage still, and also, call the Department of Agriculture and make sure that you can actually have sea hares and transport them, and also call California's DOA and see if you can bring them in. CA and FL are both very strict on what you can and cannot bring into their states, as are the Hawaiian Islands. Don't get caught bringing something you shouldn't be bringing, especially right now when they are checking carefully. You could face a large fine if they think that you aren't allowed to bring them. However, like I said, a simple phone call to your DOA should answer your question.