True the older the fish the more chance it has had to collect some toxins. Species isn't just barracuda.
Some bacteria, algae or dinoflagellateshas have some bi-products that over time builds up in the meat and can become a toxic poison problem for the person eating it anytime of the year.
ciguatera poison might just be a catch-all diagnosis for a group of similar organisms with toxins as bi-product that accumulate in fish meat.
Eat young fish our fish that have short life spans if your worried.. or better yet give it to me :-)