Goats are funny creatures. So any fish named after our silly ruminant friends automatically gains some of that hilarity. That’s why when I was browsing through the endless realm of the internet this morning, looking for a fish to write about, the goatfish leapt out at me.

Goatfish comprise the family Mullidae, which contains six genera and fifty-five species. They are found in tropical waters, usually around reefy areas. Goatfish can live in the Atlantic, Pacific, and Indian Oceans, as well as in the Mediterranean and Red Seas. They are benthic fish, meaning they tend to stay on the ocean floor, but prefer shallow areas where they don’t have to venture deeper than 100 m.

A Blue-lined goatfish sporting some nice barbels. Image by Richard Ling, CC BY-SA 2.0, via Wikimedia Commons

Like goats, goatfish come in a wide variety of colours. Unlike goats, goatfish can rapidly change their colour (side note: how cool would it be to have a colour-changing goat?!). The fish will change their colour depending on what they are doing; a fish resting on the bottom will have a different colour than a highly active fish. Goatfish sometimes swim with other species of fish, and will change their colour to match that of the schools they swim with.

Goatfish are bottom feeders, using two barbels that protrude from their chin to sweep the ocean floor for any edible meals. They will eat pretty much anything, which is where the ‘goat’ part of their name comes from. Once they’ve found a tasty animal, goatfish dig their heads into the sand, ingesting both the prey and a ton of sand. The food is swallowed while the sand is expelled through the fish’s gill covers.

A whitesaddle goatfish foraging for some food.
Image by Divervincent, CC BY-SA 3.0, via Wikimedia Commons

Goatfish don’t just use their funny barbels for foraging; they are also involved in courtship behaviour. Male goatfish will waggle their barbels at females to attract their interest. Females lay eggs in the open water, where they float until hatching. Their behaviour doesn’t change much after hatching, with the little goatfish simply dancing with the currents until they reach 5 cm in length, when they go to the bottom and start acting like real goatfish should.

In many countries, goatfish are caught for human consumption, and have been for quite some time. In ancient Rome goatfish were highly valued thanks to their colour-changing abilities: fish would be served still alive, and as they died the poor goatfish would go through a number of colour changes. I think I’d be put off by food that changed colours before my eyes, but the Romans loved it.

Cover image by jayhem from Antibes, France, CC BY 2.0, via Wikimedia Commons, cropped to fit