Sea Monsters: Dirty Fish

So I settled in to watch Mike Rowe and “Dirty Jobs” last night, as I always do of a Tuesday round about this time of year. At the same time I’m reading a fascinating NYT article that I’ve already made up my mind is going to be the basis for today’s post and then the horror begins. Mike is once again in a situation about which there is very little to envy but this time it features a bona fide sea monster that could certainly turn your stomach if not take a bite out of you.

At the header is a creature known as a sea lamprey. Sometimes they are just called lampreys. They are a simply structured, prehistoric fish (no kidding, that is a fish) that are related to the delightfully named and nicknamed hagfish, known as slime eels (Mike’s done a job with them, too). Lampreys feed by attaching their round, cone-shaped mouth to their prey and just gnawing away at whatever they stick to. The teeth are fairly sharp and the suction created by the shape of the lead digestive orifice allows them to stay put indefinitely. Or at least until their prey dies and the lamprey moves on.

The lampreys are, for the most part, Atlantic Ocean fish but they don’t seem too picky about environment. A little research this morning turned up stories noting sailors sometimes had problems with them when swimming or wading in Atlantic waters. It seems that in years after a population boom the lampreys could have trouble finding enough food for their burgeoning populations. Hungry, and decidedly undiscriminating aside from their preference for live meals, the lampreys would attach themselves to human beings and begin to gnaw. Pulling them off left the victim with a chunk of meat gone and the potential for serious infection.

These animals aren’t exactly good for the environment, either. Though they pose no threat to any specific Atlantic species as far as population is concerned, their eating habits can be devastating if they work their way into inland lakes and rivers. This is exactly what happened in the Great Lakes of Canada and the U.S. in the 1920s. A huge population of trout existed in the lakes at the time and was the source of a multimillion dollar fishing industry that employed thousands. When a canal was built to allow ships to pass from Lake Ontario into Lake Erie (ironically, for ease of shipping trout) sea lampreys used the canal as a gateway to all the Great Lakes. They devastated the trout population to such a degree that by the start of World War II all but one of the fisheries had closed and the lakes were virtually devoid of the trout, though teaming with lampreys.

Attempts to restock the lakes with trout have for the most part failed. But biologists continue to study the problem and catch and neuter the lampreys, which is what Mike Rowe was helping out with last night. On a bright note, lampreys hate human spit. Even a small amount can make a tank full of them literally jump up and even out or the tank. Something for the biologists to work on. And something for you to remember if you ever see one coming for you, mate. We'll return to our regularly scheduled posting tomorrow.