Stock structure of Lethrinus laticaudis (Lethrinidae) across northern Australia determined using genetics, otolith microchemistry and parasite assemblage composition

摘要: The grass emperor Lethrinus laticaudis is a conspicuous element of the commercial and recreational catch from nearshore reef systems across northern Australia. Australia are exposed to increasing levels fishing pressure fishers. To inform ongoing management this species, present study examined stock structure L. using combination complementary techniques. In all, 342 samples were collected 13 locations in coastal waters ranging Pilbara region Western Moreton Bay south-east Queensland. Population genetic analyses microsatellite markers demonstrated that there at least four genetically distinct populations with gene flow between jurisdictions (with significantly more separation Australian Northern Territory than Queensland locations). An isolation by distance effect was evident (genetic differences linearly distance). Otolith microchemistry parasitology indicated some spatial structuring within broader regions. These findings restricted connectivity small scales suggest vulnerable localised depletion areas where effort concentrated. This conclusion consistent recent observations fishery declines heavily fished locations.