Hyperostosis - Swollen Bones
The enlargement of particular areas of fish bones is known as hyperostosis.
Translated it means 'above normal bone growth'. The word is derived from the Greek hyper - above, osteo - bone, and osis - suffix denoting a condition.
Hyperostosis occurs in about eighty species of fishes across at least six orders and twenty families.Bone sites that are affected and how they grow appear to be fairly consistent within a species. The hump on the head of an adult Snapper develops as a result of hyperostosis.
The cause of hyperostosis is unknown. It has been suggested that it may be a response to pollution, or possibly a disease, however evidence suggests that it has a genetic cause.
Hyperostosis doesn't appear to have any effect on the edibility of a fish.
- McGrouther, M.A. 1994. Swollen Fish Bones. Australian Natural History. 24(11):79.
- Smith-Vaniz, W.F., L.S. Kaufman & J. Glowacki. 1995. Species-specific patterns of hyperostosis in marine teleost fishes. Marine Biology 121:573-580.
Mark McGrouther , Collection Manager, Ichthyology