Emergence of serranid pigment abnormality syndrome (SPAS) in wire netting cod (Epinephelus quoyanus) from Heron Island on the southern Great Barrier Reef

Abstract

Coral reefs worldwide are under increasing stress from anthropogenic impacts, but there are relatively few reports of increased rates of disease in coral reef fish. Herein we report the emergence of abnormal skin lesions in wild-caught wire netting cod (Epinephelus quoyanus) near Heron Island in the southern Great Barrier Reef. The lesion involves conspicuous darkening and disorganisation of the brown ‘wire netting’ colouration pattern typical of this species, most commonly on the lower jaw, premaxilla and head, with occasional involvement of the flanks and dorsal fin in some fish. The lesion was not present during research conducted in the mid-1990s; however, since it was first recorded in 2012, the prevalence of grossly visible lesions has increased to 16.9% in 2017, with fish >340 mm long most affected (prevalence 64.7%). These data suggest emergence of the lesion is a recent phenomenon and that causative factors may be age related. Abnormal pigmentation lesions have only been observed to affect E. quoyanus and coral trout (Plectropomus leopardus; since 2010). Given the species affected and the currently unknown aetiology of these lesions, we name the condition serranid pigment abnormality syndrome (SPAS). Further research is required to determine its geographic distribution, establish causation and describe the course of disease in E. quoyanus.