Blackspot sharks from Riau Islands, Indonesia, have a late maturity (~6 years old) and low fecundity (litters of two pups). Mature males primarily eat bony fishes, mature females primarily eat cephalopods, whereas juveniles primarily eat crustaceans. A seafood supplier who was interviewed has perceived population declines and stated that the species is mostly caught incidentally.

This study provides a historical baseline of densities, sizes and biomasses of long-spined sea urchins (Centrostephanus rodgersii) and red sea urchins (Heliocidaris tuberculata) commercially harvested on shallow reefs of New South Wales, Australia. Long-spined sea urchins occurred at higher densities than did red sea urchins and had a broader distribution and larger biomass where the fishery operates. The small biomass of red sea urchins (~3% that of long-spined sea urchins) and its restricted distribution suggests that it is vulnerable to overfishing.