Recognising the marlin species and accurately estimating the size and weight of the fish are two of the more refined skills of a gamefisherman. Its especially important when practising tag and release, as many of the statistics of todays tagging programs are influenced by your billfish species, size and weight estimates. Prepared by Dr Julian Pepperal, here’s a quick reference guide to help recognise the features that differentiate striped, blue and black marlin, and the right way to estimate billfish weights.
Graph one; shows the length/weight curve fro black marlin over their entire size range. Sizes range from 4kg to more than 600kg
Graph two; depicts average curves for blue marlin, striped marlin and sailfish in the more commonly caught size ranges. The length of the fish is measured from the tip of the lower jaw to the fork in the tail- the â€œshort lengthâ€ used in record claims. In order to read these curves, draw a vertical line from the length of the fish to the curve, and from the intersection, draw a horizontal line to the weight axis. Please note that black marlin are not included in this graph because their length/weight relationship is nearly identical to blues
What Marlin is That?