Thought to be released by aquarium owners, the Yellow Tang (Zebrasoma flavescens), native to the Indo-Pacific, has been sighted in several locations throughout south Florida since 2001. Last month, a Yellow Tang was spotted at North Dry Rocks, offshore of Key Largo in the Florida Keys National Marine Sanctuary. Thanks to the sharp eyes of a citizen scientist, this fish was identified, reported and removed from the Sanctuary within just a few days. Scientists from United States Geological Survey (USGS) helped divers from REEF coordinate the fish's live capture and removal. After a quarantine period, it will be on display in an exhibit of non-native marine fishes at Philip and Patricia Frost Museum of Science in Miami.

The Blue Tang (Acanthurus coeruleus) is a common inhabitant of Florida waters, but its relative, the Yellow Tang, is not native to Florida waters, and spotting one in this area is a cause for concern. Identification of this species can be slightly tricky, because the juvenile phase of the native Blue Tang is completely yellow, resembling the Yellow Tang. To tell the difference between the two, look at the base of the tail, where a small, sharp spine known as the "scalpel" is located. The juvenile Blue Tang has a yellow scalpel, while Yellow Tang has a white scalpel and a more protrouding mouth.

Scientists emphasize early detection and rapid response to non-native fish species in part because of lessons learned from another Indo-Pacific species, the Lionfish, which has caused detrimental impacts in its invaded range. Lionfish were first reported in Florida waters in 1985 and rapidly expanded throughout U.S. Atlantic coastal waters as well as the Caribbean Sea and Gulf of Mexico. 

If you see a non-native species in the water, be sure to report it on your REEF survey (if you are doing one), as well as through REEF’s Non-native Sighting Program form here. To learn more about non-native Yellow Tang, check out this fact sheet from our partners at USGS: