Tuesday, November 18, 2014

What the heck is that? On sea robins and their awesomenitude

Florida is home to an incredible diversity of fish species, so it is unsurprising that every once in a while something weird comes up on an angler’s hook. Most of us can easily identify the common species, like snook, redfish and trout; but what would you say if you got this guy on the end of your line?

Answer: “Awesome! A sea robin!”. Sea robins (also called gurnards) live all over the world in tropical and temperate waters. Sea robins like to hang out on the bottom, though they do swim through the water column from time to time. There are many different species of sea robins, at least 7 of which are found in Florida waters.

Sea robins have hard bony heads, but what really makes them cool are their pectoral fins: the lower three fin rays are modified to form what look like fingers, which they use for support and to search for food. Check out this youtube video to see them in action as they "crawl" across the seafloor:

Sea robins are also known to vocalize, or make drumming or croaking sounds. Fish use many different methods to produce sounds, depending on the species. Some make noise by grinding their pharyngeal teeth together (pharyngeal teeth=teeth located in the pharyngeal, or gill, arches of fishes). Others, including the sea robin, have a special muscle which they vibrate against their swim bladder to make noise; this is the same method that drums use to vocalize. Check out this video to hear some sea robin vocalizations:

In the state of Florida, there is very little targeted fishing for sea robins, though leopard sea robins are sometimes caught commercially for bait or for the marine ornamental trade (for use in aquariums). For the most part, Florida anglers don't target sea robins, but that doesn't mean they don't occasionally catch or snag them, so they still come up on lines from time to time. They can also be seen while diving or snorkeling, as many species inhabit shallower waters. So keep an eye out for sea robins next time you are on or in the water!

For more on sea robins see:


FAO guide

FWC leopard sea robin regulations