The Double Life of an American Lake Monster

All was on the White River as the sun set. A PhD student at Michigan State University sat on her gently bobbing research boat listening to the evening chorus of frog croaks and red- winged blackbird songs A series of taps from a small speaker signaled that a sea lamprey was moving through the depths below.

There is a decades-long effort between the US and Canadian governments to control the population of the sea lamprey. While the Great Lakes are home to four species of native lamprey, the sea lamprey slithered in from the Atlantic Ocean more than a century ago.

The sea lampreys that were pulled from the large aquarium at the Great Lakes Fishery Commission lab were suckered onto the tank walls and were in danger of dying. The lampreys took some expertise to handle, but they lashed chaotically until the doctor relaxed them into wet noodles. She said that she did a lot of banana surgeries.

The sight of a sea lamprey can make a person queasy. The animal has yellow-brown skin and a swimming style that makes it look like an animal. The mouth is made of a cup with rings of teeth and a tongue in the center. This mouth is similar to a leech and can cause serious wounds or death.

The sea lampreys were villains by the 20th century. The most bloodthirsty fish found in the Great Lakes and on the Atlantic coast is a round-mouthed creature that looks like a two-foot piece of garden hose. Thevilement has continued. In the film Blood Lake: Attack of the Killer Lampreys, a lakeside town in Michigan is plagued by human-hungry lampreys that burst from corpses, kill the coroner, enter the municipal water system, and murder the mayor as he sits. The end of the movie shows the lampreys' ability to survive when the town recovers from the massacre.

The image of the lamprey has been used against them. The deputy executive secretary for the Great Lakes Fishery Commission doesn't like sea lampreys They don't look like animals. If you want to get rid of them, you don't have to make a case.

Michigan State University has laboratories dedicated to the study and control of lampreys. Even after they have been sliced in half, lamprey skeletons are still able to regenerate fully functional spine cords. They have an amazing olfactory power that is comparable to being able to find a few grains of salt in a swimming pool. Native populations live in salt water and then swim to inland tributaries to die. The lamprey species have lived on Earth for hundreds of millions of years.

The sea lamprey has earned a grudging admiration from the people who are supposed to wipe them out. You have to have respect for an animal that has been around for a long time.

Petromyzon marinus first entered Lake Ontario sometime in the 19th century. On its southeastern edge, the rushing 3,100 foot span provided a natural barrier that blocked the species from further eastward expansion, but the Welland Canal offered an alternative access route. Sea lampreys encountered a large amount of native aquatic species in the Great Lakes. Millions of fish were killed and blood and bodily fluids were sucked out by the lampreys. Their spread was not deterred by any predator.

Humans felt their presence as the problem got worse. Four in five commercially caught fish were too wounded by lampreys to be sold. Less than five years later, only 11,000 pounds of lake trout were caught in the whole of the lake. Regional fisheries lost tens of millions of dollars each year due to lampreys and pollution. Commercial fishers told Congress in 1949 that their industry was in trouble. Residents and fishers recoiled at the parasites. In Great Lakes Sea Lamprey: The 70 Year War on a Biological Invader, a woman said that people thought they were horrible creatures.

Wildlife managers and locals fought the sea lamprey with everything they had. Few weapons were tested. Barriers were built to block migrating adults from reaching their spawning grounds and new equipment was used to kill larvae. Operators built a booby trap out of a metal ramp that led lampreys over the dam's edge and into a bucket of oil. MarvinNorton led sporting clubs on excursions to hunt and spear lampreys The efforts failed. Gerald Cooper of the Michigan Department ofConservation thought that the lamprey would be with the dog from now on.

The control measures leave enough lampreys to reestablish a strong new generation.

Scientists at the US Geological Survey were looking for a solution to the problem. They lucked out with the 5,206th formula they tested, which was 3-trifluoromethyl-4-nitrophenol. The researchers were excited that TFM was able to spare most native biota. The novel lampricide was pumped into Michigan.

TFM was a powerful weapon within 20 years. More than half of the sea lampreys' potential spawning habitat was blocked by the abundance of dams in the region. The number of lampreys in Lake Superior dropped by 92 percent by 1978 The lamprey population in the Great Lakes has fallen from 2 million in the 1950's to a few hundred thousand today.

The population is kept within limits by the dam and lampricide. These techniques are at risk of failing. The dam that corrals lampreys into a manageable area are falling into disrepair. Most of the country's roughly 90,000 dams are more than 50 years old. Heavy rains in Michigan in 2020 led to the displacement of 11,000 residents and $245 million in damages. As a result of cost and ecological damage, it is unlikely that the US will continue to invest in this aging infrastructure.

It's not a good use of lampricides. It is possible that they may not be sustainable. Stores are vulnerable due to the fact that there are only two suppliers of TFM in the world. The lamprey has a risk of evolving resistance. The Great Lakes lamprey species, which lack the ability to detoxify the chemical, are harmful to some animals. Gaden says that it is a great tool. If there is an alternative to pesticides, we want to use it.

Complete eradication is seen by many as an ideal but impossible goal. More than 5 million sea lampreys have been eliminated from the Great Lakes so far this year, thanks to lampricide. Several thousand offspring typically survive to adulthood when there is a single gravid female. Control measures with a 98 percent success rate leave enough lampreys to reestablish a strong new generation. Humans fight the same war every year. The people are wily. Gaden said they were slippery. They will find a solution.

A group of scientists across the ocean want lampreys to overcome human hurdles.

The sea lamprey is not as abundant as its cousins in the Great Lakes. The species is in distress due to poor water quality, damming, rising temperatures, and likely overconsumption. Less than 20% of historically suitable habitat is left for lamprey populations in Spain and Portugal. Philippe Janvier is a paleontologist with the Museum National de l'histoire Naturelle in Paris. We might just have the fossils.

The coin needs to be looked at as two sides of the same coin.

Sea lampreys are not reviled in Portugal, Spain, and France. Sea lamprey was considered a delicacy by European elites due to it's texture and taste. At banquets, Julius Caesar gave his men lampreys. They were a symbol of ostentation and could fetch 20 gold coins for 100 fish. It is said that King Henry I overdosed on lampreys. Queen Elizabeth was the first to not serve lamprey pie due to the decreasing number of lampreys. The queen's were able to get lampreys from the Great Lakes because they were hard to find in Europe. High mercury levels of the US fish prevent them from being imported to Europe.

Pedro is looking for ways to grow lamprey populations instead of suppressing them. His mission is aided by the work of researchers across the pond. Each group of researchers tries to understand lamprey biology more precisely in order to control their populations in the Great Lakes and Western Europe. Margaret is a lamprey Biologist at the University of Manitoba.

Knowing the intimate workings of lampreys can help researchers. A lot of lamprey research is dedicated to their show-stealing sniffers. One big nostril is what they are. Scott and another lamprey specialist are trying to make a sex pheromone that is invisible to the lampreys so that they can't reproduce.

A chemical barrier called "alarm cue" was used in the experiment to manipulate the lampreys' movements. The extract makes lampreys jump into the air to escape. The alarm cue pumped into the river could be used to push lampreys into traps or away from spawning habitats.

The lamprey's mouth is being manipulated by researchers. The researchers are testing a gridwork of copper wires that can be used to map the mouths of lampreys. Scientists hope to create a device that can identify lampreys by their suckers using machine- learning. They envision a fish passage that blocks traps, kills lampreys, and allows all other fish to be shuttled upstream.

Petromyzon marinus has challenged biologists to match its ingenuity.

There could be a new avenue for messing with lampreys sex lives. It's possible to boost the number of lampreys of either sex and make the population too balanced for effective breeding. There are a few obstacles to overcome. To assess the impact of genetic alterations, researchers will need a reliable supply of lamprey embryos, which are small and fragile, and are costly to collect from local rivers. Scientists will need to complete the animal's complex and migration-driven life cycle in the lab in order to deploy high-techgenomic weaponry.

Petromyzon marinus has challenged biologists to match its ingenuity and will to find a way.

In Michigan, Nick Johnson stood thigh-deep in the clear water and pointed to the pebble and shell-littered bottom. After a moment, a pair of lampreys, engaged in an intimate act, came into view.

The female was plump with small sesame-seed-like eggs and was picked up by Johnson. She didn't retreat because breeding marks the end of a lamprey's life cycle, so she had lost either the instinct or the energy to flee. Johnson was able to expose her brood.

The lamprey, a graceful and well-adapted animal, completed her years on Earth with one final act. The lampreys have wreaked havoc in the Great Lakes but up close, they looked peaceful.

The lamprey's notorious bloodlusting mouth might be less villainous than we think. He put a lamprey on his bare hand after pulling it out of a trap in the water. The fish's mouth pulled with a force similar to a vacuum cleaner as it latched on. One of the authors of this story received a mark like a braces-lined hickey from the prickly feeling on the skin.

It is more difficult to see the species as bad in its preferred breeding habitat. Our relationship to animals is shaped by where humans meet them. The sea lamprey isn't the only problem. Depending on where you are in the world, a variety of organisms are both invaders and victims, cast in human eyes as villains or victims.

Efforts to conserve or conquer the sea lamprey will be difficult due to climate change. Evidence suggests that warmer waters will speed up lamprey life cycles and make the use of lampricide more frequent. The lampreys might be able to lay more eggs. New habitats could be opened up due to extreme storms. It's possible that rising temperatures will encourage pesticide resistance while nudging the species northward into Lake Superior.

Climate change may affect southwestern Europe differently. Warming is predicted to increase the occurrence of 100 year droughts that can dry out critical lamprey spawning runs. There is a possibility that the supply of fish that feed lampreys will diminish. The Iberian peninsula may be leaving for warming.

Humans on both sides of the Atlantic will keep pushing and pulling with the sea lampreys. The square inch on the planet is not the same as it was in the past. We need maintenance for the rest of our lives.

One of the researchers in Michigan accepts the paradoxes more easily than anyone else. In Scotland, sea lampreys are the most rare of all native lampreys. He enjoys every aspect of the lamprey, even though his current work is to eradicate them from the Great Lakes. They are fascinating models of ancient evolution, and they are also tasty. When he looks at a lamprey, he remembers the wonder he felt when he flipped over logs and rocks to find what was hidden underneath. It just feels right when I see a lamprey in the water.

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