Found in the tropical surface waters of the Indian and Pacific oceans, the Indo-Pacific sailfish is a pelagic species rarely seen on inshore reefs. It has a long, slender body with an average length of 270 centimetres. It is metallic
blue on top and silvery underneath, with vertical bluish bars across the length of its body. Indo-Pacific sailfish are easily identified by their long, sharp bill and their sail-shaped dorsal fin.
They use their bill (an extension of their upper jaw) to stun shoaling fish including anchovies, mackerel and sardines. Some scientists believe that when held above the water, their sail acts as a cooling device, helping to disperse heat after sudden bursts of speed. Indo-Pacific sailfish are highly migratory, with top speeds of over 100 kilometres an hour.
Also known around the world as a silver or white marlin, the black marlin is found in the tropical and subtropical waters of the Indian and Pacific oceans. It prefers warm, coastal waters, and is the only marlin species with rigid pectoral fins.
Other distinctive characteristics include its proportionally low dorsal fin; and its bill, which is shorter than that of other marlin species. It is slate blue on the upper half of its body and silvery white on the bottom half. Some black marlin have light blue vertical stripes.
With estimated top speeds of almost 130 kilometres/ hour, it is one of the fastest fish in the sea; while a record length of 4.65 metres makes it one of the largest bony fish. Black marlin hunt on the surface, feeding predominantly on squid and smaller pelagic fish.