The marine lamprey of the Atlantic Ocean have made their way inland to fresh water lakes formerly denied them, infesting the Great Lakes and the tributary rivers that feed into them. A dramatic loss of bio-diversity is resulting as efforts to curtail their population and spread is underway.
Efforts are ongoing to slow or reduce the invasion, but no practical and permanent solution exists at this time. Scientists have studied over 3000 different chemical aids, searching for the best lampricide that does as little damage to local fish and wildlife populations as possible. The best efforts only slow the damage, such as the selective pesticides such as “TMF” ( 3-trifluoromethyl-4-nitrophenol) that targets only lampreys, and use of netting and artificial damming to prevent the spawning migration of this pest. Other control measures such as use of another granular preparation called “Bayluscide” which is more cost-effective and also targets the larval stage of the lamprey. This preparation can have potential harm to desirable local fish so this agent is used only in specific circumstances (during certain hatching or migration occurrences) where it will do the most good at eradication of the lamprey larvae and the least harm to other species.
The marine creatures known as lamprey are not true eels or are they correctly called a fish for they lack certain attributes of either.
These ocean-going creatures enter fresh water to reproduce. Due to the activities of man in the previous and current centuries, they have found ways into fresh water lakes that formerly were unavailable to them. Presently, they inhabit all of the Great Lakes and the Finger Lakes as well, and many rivers and tributaries thereof.
They wreck havoc on local species in their feeding cycle, for which local fish have no developed defense against. It is believed that there are millions of them in the new territories of these fresh water lakes. They critically damage the fish they feed upon, creating large open wounds where they rasp away at the flesh and tissues for their food, drinking the blood of their victim. Only about one of every 7 fish will survive an encounter with these water vampires. In the 1950s, nearly every fish caught in Lake Huron showed signs of lamprey attacks, some with as many as ten separate wounds! The sport fishing industry was nearly devastated.
Western culinary tastes do no consider the lamprey eel to be edible so there is no marketability for them. In some European countries like Portugal they are considered to be a delicacy and thus, there is a sustaining market for them. Smoked eel is also a delicacy in Poland. Lamprey are also eaten in the countries of Spain, France, South Korea, Sweden, Finland and the Baltic nations. In The U.K. they are usually used as bait for fishing (dead and cut up) and not for consumption.