You may have heard of Neon Gobies, Clown Gobies and Cleaner Gobies, but have you heard of Helper Gobies?
According to a study published in the Journal Science, when a species of coral, Acropora nasuta is threatened by an invading species of toxic seaweed, A. nausuta sounds the alarm by releasing a chemical signal. Within minutes of sounding the alarm, heroic Helper Gobies enter the scene and remove the killer seaweed.
In a world where coral populations are vanishing before our very eyes, the results produced by these Helper Gobies are impressive.
In corals occupied by the gobies, the amount of offending seaweed declined 30 percent over a three-day period, and the amount of damage to the coral declined by 70 to 80 percent. Quote from Newswise
So who are these Helper Gobies? The two species of goby that came to aid of the threatened coral were: Gobidon histrio (sometimes called the Broad-barred Goby) and Paragobidon enchinocephalus (the Redhead Goby).
How do the Helper Gobies help? In the case of Gobidon histrio, the Broad-barred Goby eats the noxious seaweed, which in turn is thought to make the fish more noxious and less apt to be eaten by predators. Paragobidon enchinocephalus, on the other hand, simply mows down the offending seaweed without eating it.
Why do the Helper Gobies respond to the chemical distress call?
When I first started reading up about this study—the first thing I thought is that the presence of the seaweed was like ringing a dinner bell—but it turns out the potent seaweed isn’t eaten by the Redhead Goby at all. Furthermore, the presence of the seaweed itself did not cause the Helper Gobies to react—so their primary motivation was not food.
My next thought was that perhaps the seaweed presented a toxic threat to the Helper Gobies themselves—but that doesn’t appear to be the issue either. In fact, an article on newswise even suggests that Gobidon histrio, the Broad-barred Goby, benefits by increasing it’s own level of toxic protection by eating the invading seaweed—and again I note that the seaweed itself, or presence of the toxic chemicals extracted from the seaweed itself, did not summon the Helper Gobies.
What’s absolutely fascinating about this story is that the Helper Gobies react to a distress call sent out by way of chemical messaging (…I wonder when my iPhone will be able to send out chemical messages. Undoubtedly, the politicians have already figured out a tax for that…) and the Helper Gobies arrive on the scene to help clean up the coral.
In exchange for their Helper Service, the corals receive shelter and food (in the form of a nutrient-rich mucus which they nibble on and algae which grow at the base of the coral).