Once a year, on the same few days, at the same corner of the same reef, thousands of them arrive.
This species is one of the great aggregation spawners. Fish that spend the year spread out over hundreds of square kilometers converge on a specific site, usually a reef pass or a promontory where current runs off the reef, in numbers that turn empty water into a crowd. They spawn around the full or new moon, over a handful of days, and then they leave. The current carries the eggs off the reef and away from everything that lives on it.
It works, and it is also the species' greatest weakness. Every fisher in the region also knows the site and the date. An aggregation can be fished out in a few seasons, and when it goes it does not come back: the site is learned behavior passed down by fish that keep returning, and once the fish that knew it are dead, nobody teaches the next generation. Aggregations have gone extinct while the species survived elsewhere.
Square tail rather than crescent, small blue spots, up to eighty centimeters. Like most large groupers it also appears in ciguatera records, which is a good reason to leave it alone.
The genus. Plectropomus Oken 1817 - plectrum (spur) + pomus (lid or covering). ETYFish
The species. Plectropomus areolatus (Rüppell 1830) - with areolae. ETYFish
- tail cut square across the back edge, not crescent-shaped
- small blue spots scattered over the head and body
- up to 80 cm
- often near reef passes and channel mouths
