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Black Marlin: All You Need To Know
Black marlin is a fish, belonging to the phylum Chordata, Kingdom Animalia, family Istiophordae and class Actinopterygii. This species is seen in the Indian ocean and Pacific ocean warm waters. There are 7 variants of marlin and it is one amongst them.
The black marlin fish is a very fast fish, which leaps out of the water, and thus is a prized possession to the sports fishers. They are also very durable. The upper side of the fish is dark blue in color and the beneath side is white to silver color.
On the sides of this fish, there are very light blue stripes. Excluding the dorsal fin, which is blue or black in color, all the other fins are dark brown in color. Out of all the 7 variants, these are the only species without any retractable fins.
The food of this species is smaller fishes like the sword fish, tunas, mackerel, octopuses, squid, dolphin fish, cuttlefish and other invertebrates. To catch hold off their prey, they use their elongated sharp bills. Within the water they are found at quite depth like on corals, and even at times near the coast.
Usually, they are found at a depth of 30 meters, but they do exist at depth of 915 meters. They are also seen in the Indian and Pacific ocean, as well as in temperate waters. The predators of this fish are humans, who will either hunt them down for selling purpose or keep in the form of a possession.
The reproduction is external and is done on the grounds. The liberation of eggs is done in warm waters, upon fertilization of sperms and eggs. A females liberates around 40 million eggs.
Fun Facts About Black Marlin!
It is an excellent swimmer and is seen in Indian and Pacific Ocean warm waters, and can move really quick and migrate as well.
i. Speedy Swimmers
Amongst the 10 fastest animals, it stands out. This species of black marlin has exhibited a record of 22mph-50mph. Other records have said that they can travel at a speed of 80 miles within an hour, which is more than the cheetah’s speed. Thus, making it a possession for the fish hunters.
Their body shape is fusiform, which means the ends are narrow and the other part is wide and the tail looks like half-moon, which helps them to move rapidly. They are also called as bill fish, due to their rapid speed and is one of the fastest and strongest fish throughout the world.
ii. Migrate Long Distances
The movement of these fishes have been tracked and it’s said that they migrate long distances like 8000km. for instance Two marlins were tagged at Australia and were found at the India and Sri Lanka coast. This tagging of animals, helps in understanding the migration timing, durations and the period.
iii. Growth Rings
Black marlin grows in size quite fast, but the size depends, whether it’s a female or male. The fish which is one year old has a weight of 15kg and around 50, after 3 years. In this species, females are huger than males.
In cases, the females, are around 450kg, when its around 12 years old, whereas males are around 200kg. Another way of finding the age is to observe the rings on the dorsal fin and the spine.
Determining the age of an animal is important as it helps to assess the conservation strategies and its number. Another way of determining is by counting the bands on its ear, which are the otoliths.
Black Marlin Citations
- Misidentification of istiophorid billfishes by fisheries observers raises uncertainty over stock status. J Fish Biol . 2018 Aug;93(2):415-419.
- Environmental influences and ontogenetic differences in vertical habitat use of black marlin ( Istiompax indica) in the southwestern Pacific. R Soc Open Sci . 2017 Nov 1;4(11):170694.
- Dispersal of adult black marlin (Istiompax indica) from a Great Barrier Reef spawning aggregation. PLoS One . 2012;7(2):e31629.