Yellow Boxfish

Yellow Boxfish

The Yellow Boxfish is another of the great variety of fish and marine life that Koh Tao diving has to offer.

Yellow boxfish are hard to find when diving around Koh Tao
A cute yellow boxfish


Ostracion cubicus can reach a maximum length of 45cm, the ones I have seen here while diving on Koh Tao have been no more than 10cm, bright yellow and cute.

Yellow boxfish are normally hiding from scuba divers
A brave yellow boxfish swimming above the corals

Boxfish are also known for their armored and rigid (box) body which in most cases makes it hard to move but it has evolved their own style of swimming called ostraciiform locomotion.  The body is made from armor plates with holes for the eyes, mouth, tail, and fins.  When young it is bright yellow in color and as it grows and gets older the brightness fades and very old specimens will have blue-grey to black coloration with faded yellow.  They are solitary fish except at breeding time in spring when males hang around with up to 4 females.  Their diet is mainly marine algae, worms, sponges, crustaceans, mollusks, and small fish.

Yellow boxfish hiding under a rock, they can be seen by those doing their open water course
A yellow boxfish looking at a diver

Where Can You Find It On Koh Tao?

The Yellow Boxfish are hard to find on the dive sites around Koh Tao, I’ve seen them the most at White Rock dive site hiding in the staghorn coral with their little fins going.  But they can be found around Asia, Indian, and the Pacific oceans.

What Do Yellow Boxfish Do?

It looks small and cute but when injured or stressed it releases the neurotoxin tetrodoxin (TTX) from its skin that may prove lethal to the fish in the surrounding waters.  The bright yellow color and black spots are a form of warning coloration to any potential predators.  They can be very frustrating to divers and photographers as they go deeper into corals and holes when approached.  If you are looking to take a photo approach slowly so as not to spook it.  Being careful of your buoyancy and equipment so you do not damage the marine environment or equipment.

Koh Tao diving has lots of cool creatures to find
Yellow boxfish like to hard from divers

You can find out more about learning to identify fish by studying the Fish Identification course, everything including the exam can be done completely on line.

SSI Fish Identification can be done completely online
SSI Fish Identification Card

What Next For Your Diving on Koh Tao?

So if you are interested in Koh Tao diving contact us and you can find out more about the diving we offer by clicking on the links below:
Try Scuba Diving
Open Water Course
Advanced Course
Fun Dives

What Other Scuba Certifications Can I Get On Koh Tao?

Sea Turtle Ecology
Nitrox Speciality
Wreck Diving Special

Want to know more?

How do I get to Koh Tao?
When is the best time to dive on Koh Tao?
How to choose a Koh Tao diving school
Find out more about the SSI diver training agency here: Dive SSI Registering on SSI is completely free and gives you access to lots of information on dive courses, professional training, dive sites around the world, and special offers.  You can download a free app onto your phone to make this easier.

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