Sailfish – Istiophorus platypterus
The human race is generally a bit, dare it be said, ‘uneducated’ with regards to the ocean and all that she holds. Leisure Boating will look at different ocean species every month with the aim of giving our readers a closer look at the wide range of life forms that lurk below.
There are two species of sailfish; the Atlantic sailfish and the Indo-Pacific sailfish. However, it has been debated whether the two should be classified as separate species seeing as very little evidence exists to distinguish the two. Some scientists believe that there are morphological differences, with the Atlantic sailfish typically reaching far smaller sizes than its Indo-Pacific cousin. There is, however, no conclusive evidence and we’ll treat it as one single species in this edition of WTF.
Sailfish, commonly known as ‘sailies’, are spectacular gamefish loved by sportfishermen all over the world. It gets its name from its prominent sail-like dorsal fin which runs along the length of its body and when extended, is taller than the width of the body. There’ve been speculations by marine biologists as to whether the ‘sail’ may serve the purpose of a cooling/heating system. The theory was developed due to the large number of blood vessels that exist in the sailfish’s dorsal fin and because of the sail-raising behaviour at or near the surface just before or after high-speed bursts or chases.
The sailfish has a slighter build than its other billfish counterparts with a slender elongated body built for high speeds and a long, pronounced upper jaw that forms a pike-like circular bill. While the ‘sail’ is metallic blue/black, the upper part of the sailfish’s body is dark blue and the flanks and belly varies from silvery white to a coppery hue with occasional brown spots. Along its sides are 20 rows of vertical bars made up of tiny light-blue spots.