Animal of the month - Cow Fish


I absolutely love these little guys! We were lucky enough to bump into one at Turtle Heaven yesterday whilst on a drift dive. With their shocked expression and slow, sluggish swimming technique, they really are a joy to watch whilst passing over the reefs around the Gilis. 

Larger than ones I have seen in the past, this particular Longhorn Cowfish, or Lactoria cornuta, was about 6 inches long. Not so big considering they can grow up to 20 inches! 

Common in Indo-pacific waters, the cowfish tends to hang around coral reefs, in particular Acropora coral when juveniles. When all grown up they tend to be quite territorial and hang out near protected reef flats. They have been found up to 100m below the surface! 


Part of the box fish family, it gets it's name from the two horns atop it's head. These are believed to have evolved to help make the little guy more difficult to swallow by it's predators. It's main predators are big eye tuna and Albacore. 

The cowfish is know to make a loud grunt if stressed or pestered, but please don't try to catch them! Although, this would be very easy as they do swim rather slowly. 

Their horns can break off quite easily. However, they can go back fully within a few months. 

The cowfish munch their way through the day, feasting on algae, mollusks and small crustaceans. They can be green, orange, or yellow in colour, with white or blue spots. 


Similar to other box fish, the cowfish' skin is poisonous. When threatened they release a toxin called ostacitoxin. This can be harmful to others around them, including their own kind! 

So keep an eye out for these little guys. They are quite fun to watch. Try not to spook them though or you may hear them shout!