In Japan they eat Kawahagi, which I think is the same trigger fish. I have had sashimi and the liver is ground down with soy sauce and some raw ginger. It looks horrible but tastes really good. You can also ea the liver sashimied. Never heard of a problem with Ciguatera.
Season is usually summer.
Here are a couple of links:
Seasonal Fishes 7: Kawahagi/Thread-sail Filefish « SHIZUOKA SUSHI & SASHIMI: The other Jewels of Japan
Encyclopedia of Sea Fish | Cooking a La Carte | How to carve fish | Kawahagi
Season is usually summer.
Here are a couple of links:
Seasonal Fishes 7: Kawahagi/Thread-sail Filefish « SHIZUOKA SUSHI & SASHIMI: The other Jewels of Japan
Encyclopedia of Sea Fish | Cooking a La Carte | How to carve fish | Kawahagi