In the Solomon Islands one Hong Kong company was even described by an ex-employee as using spotter planes and expert Chinese fishermen to locate likely grouper spawning sites using reef topography. Accounts obtained from fishers in the Philippines and Indonesia reveal that they, also, are discovering increasing numbers of grouper spawning aggregations as the depletion of shallow-water resources forces them to dive deeper and further from shore. One group of Indonesian fishers said they got such high catches from spawning aggregations they recently discovered that they no longer bother to fish for the trade during the non-spawning season. Such fisheries are not sustainable. Marine resource managers should consider banning fishing on grouper spawning aggregations for a second reason.
Gravid females are reportedly subject to significantly higher mortalities during shipment.
The fish are treated with the anaesthetic MS222 prior to air shipment. This often causes gravid females to release eggs into the water of the shipping containers. The eggs clog their gills and probably also remove oxygen from the water. This appears to be one of the reasons for the higher mortalities, according to shippers, even among fish that are in prime condition. Some Australian live reef fish companies operating on the Great Barrier Reef have recognised that targeting of spawning aggregations is not in their own long-term best interests and actively support closing the fishery during spawning months.