That Fish Blog – Aquarium Advice and Information
Cory here. The invasion of the Volitan Lionfish (Pterois volitans) has many concerned for the future of fish populations in the Caribbean and off the waters of Florida. The lionfish are swallowing native baby fish at an incredible rate, leading experts to believe this will begin to thin fish populations. Along with commercial fishing, the future is beginning to look bleak. The lionfish have spread throughout the eastern waters of Florida and are even being found along the shore of New York and Long Island. Wreck divers off of the North and South Carolina waters are finding an abundance of Lionfish. How can this be, a warm water fish in the cold waters of the Mid Atlantic and New England Coasts?
The answer is the Gulf Stream. The Gulf Stream is a current that starts in the Gulf of Mexico, flowing around Florida and up the East Coast of the United States. The current begins to flow further off shore of New England, passing the Southeastern shores of Newfoundland and out into the Atlantic Ocean. The current transports warm water from the Caribbean, the whole way to Europe. The Gulf Stream has a large impact on coastal temperatures not only along the east coast, but in Europe. Along with the warm water are tropical fish, which also make the trip along the Atlantic coastline.
There have been Spot-fin Butterflies (Chaetodon ocellatus), juvenile Blue Angels (Holacanthus bermudensis), and even small Barracuda spotted by divers off the coast of Rhode Island. In the north, during the fall, divers and snorkelers go in search for tropical species for personal and public aquariums. The sad part of this all is tropical fish caught in the stream will inevitably die as they are carried into cooler waters. Some of the best fishing from North Carolina and northward can be found off shore in the Gulf Stream where water temperatures can be close to 20 degrees higher just 150 to 200 miles offshore. Here Tuna, Wahoo, and Mahi can be found throughout most of the year. The clarity is just as amazing as the temperature difference, going from no visibility to over 100 feet in just 50 miles or so.
Typically, large or adult specimens are not found far from their native waters, because they can swim against the current, which averages around 4 MPH. Normally, juvenile fish or larvae are found due to immaturity, or the inability to fight the push of the current. The biggest question yet is how do these fish make it to the coastal waters of New England, which is 200 to 400 miles away from the Gulf Stream? The logical reasoning at this point is that they are carried toward the coast in small warm water eddies that break off the main current. Otherwise, the juvenile fish would have to swim hundreds a miles away from warm water into the colder water to only die a month or two later.