Hundreds of feet below the surface of the Caribbean Sea, a lionfish stalks its prey. It splays colorful fins, darts forward — then gulp! A tiny, brightly colored fish disappears into the predator’s stomach. Scientists in a nearby submarine caught this deep-sea drama on film. Then they realized something disturbing. The lionfish’s snack had been a brand-new, unnamed species.
“The coloration on [the prey] was so dramatic and so brilliant. It had this big bright orange-yellow stripe down the side and these huge eyes,” recalls Luke Tornabene. He works at the University of Washington’s School of Aquatic and Fishery Sciences in Seattle. A biologist, he studies the diversity of deep coral reefs. And he has just helped describe and name the new lionfish-prey species. It’s now called Palatogobius incendius (Pah-LAT-oh-GO-bee-us In-SEN-dee-us) — or the ember goby.
Deep reefs are full of undiscovered creatures. “Every trip to a new location,” Tornabene says, “we find three or four new species.” Unfortunately, in the Caribbean, his team also has been spying a lot of lionfish.
That large, showy fish is not native to the Caribbean or to the Atlantic Ocean. Yet it thrives in each, chowing down on native species. Most attempts to reduce lionfish numbers rely on human divers. But this fish has been feeding and breeding at great depths — up to 122 meters (400 feet). Most divers can’t descend more than 40 meters. So their efforts have focused on getting lionfish that patrol shallow water.
Tornabene felt troubled when he first saw the invasive fish in the deep reefs. He realized it could be eating species we don’t even know about yet. That video “confirmed our deepest fears,” he now says. His team described the new goby and its lionfish threat May 25 in PLOS ONE.
In the Caribbean, the lionfish already threatens 21 known fish species with extinction. This comes out of a recent report from the International Union for Conservation of Nature (IUCN). Most of these threatened fish, including other types of gobies, live on shallow reefs. But no one knows whether or how many deep-reef denizens might also be endangered. Researchers simply don’t have enough information about them.
Stephanie Green is a marine ecologist at Stanford University in California. She was not involved in the ember goby discovery. But the video “shows how much work we have to do in these deep places,” she says. Lionfish could hunt species to extinction before they are even discovered. Then scientists would never know they ever existed.
Thankfully, the ember goby population seems plentiful. But many species remain undiscovered. And the clock is ticking. Argues Green: It’s urgent that researchers document deep reefs before lionfish alter them entirely.
aquatic An adjective that refers to water.
Atlantic One of the world’s five oceans, it is second in size only to the Pacific. It separates Europe and Africa to the east from North and South America to the west.
conservation The act of preserving or protecting something. The focus of this work can range from art objects to endangered species and other aspects of the natural environment.
coral Marine animals that often produce a hard and stony exoskeleton and tend to live on reefs (the exoskeletons of dead ancestor corals.
denizen The inhabitant of a particular environment.
diversity (in biology) A range of different life forms.
ecology A branch of biology that deals with the relations of organisms to one another and to their physical surroundings. A scientist who works in this field is called an ecologist.
endangered (in conservation biology) An adjective used to describe species at risk of going extinct.
extinction The permanent loss of a species, family or larger group of organisms.
goby A small, usually marine fish that often has a sucker on the underside.
International Union for Conservation of Nature (or IUCN) A global network of governments and public organizations, based in Gland, Switzerland. It is dedicated to helping the world “conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable.” The group, created in 1948, is today best known for using science to establish lists of species that may be threatened with (at risk of) extinction or endangered (at imminent risk of extinction).
marine Having to do with the ocean world or environment.
native Associated with a particular location; native plants and animals have been found in a particular location since recorded history began. These species also tend to have developed within a region, occurring there naturally (not because they were planted or moved there by people). Most are particularly well adapted to their environment.
population (in biology) A group of individuals from the same species that lives in the same area.
predator (adjective: predatory) A creature that preys on other animals for most or all of its food.
prey (n.) Animal species eaten by others. (v.) To attack and eat another species.
reef A ridge of rock, coral or sand. It rises up from the seafloor and may come to just above or just under the water’s surface.
sea An ocean (or region that is part of an ocean). Unlike lakes and streams, seawater — or ocean water — is salty.
species A group of similar organisms capable of producing offspring that can survive and reproduce.
submarine A term for beneath the oceans. (in transportation) A ship designed to move through the oceans, totally submerged.
U.S. Geological Survey (or USGS) This is the largest nonmilitary U.S. agency charged with mapping water, Earth and biological resources. It collects information to help monitor the health of ecosystems, natural resources and natural hazards. It also studies the impacts of climate and land-use changes. A part of the U.S. Department of the Interior, USGS is headquartered in Reston, Va.
Journal: L. Tornabene and C.C. Baldwin . A new mesophotic goby, Palatogobius incendius (Teleostei: Gobiidae), and the first record of invasive lionfish preying on undescribed biodiversity. PLoS ONE. Vol. 12, May 25, 2017. doi: 10.1371/journal.pone.0177179
Report: C. Lindardich, et al. The conservation status of marine bony shorefishes of the greater Caribbean. Gland, Switzerland: IUCN, 2017. doi: 10.2305/IUCN.CH.2017.RA.1.en