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(Click for large pic. 22Kb)
The Hammerhead is readily recognised by its grotesque hammer-shaped head with the eyes carried at the outer extremities. It is uniformly grey or blue-grey above shading to creamy-white below; the first dorsal fin is remarkably high; the teeth are broad-based, notched, offset triangles, and are comparatively small. This shark is common in open ocean waters, but more especially the young will enter coastal bays. Although considered dangerous to man in other parts of the world, including localities as close as New Guinea, it is not a proven man killer in Australian waters. The Hammerhead reaches a length of 6 m (20 feet), but in Queensland waters specimens over 4.6 m (15 feet) are uncommon. The largest recorded locally was a 4.44 m (14-foot 7-inch) male. The young are born alive; in South Australia as many as 37 have been taken from a female. It is common to find broken-off stingray barbs embedded in the jaw cartilage; presumably rays are a common, feature of the diet, together with mullet an d Australian salmon. The greatly-expanded and flattened head of this species appears to function as a hydrofoil, enabling the Hammerhead to make very precise alterations of course at slow speeds-as will be attested to by any reef-fisherman who has lost Snapper or Sweetlip to the effortless approach of a 3-metre (10-foot) Hammerhead. It is noteworthy that the leading edge of the "hammer" carries a deep groove running from the snout to each nostril (set near the eye). The flow of water along this slot appears to provide the shark with a directional facility for precise chemo location of food.
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