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What Are The Most Dangerous Creatures in Lake Michigan

What Are the Most Dangerous Creatures in Lake Michigan?

Lake Michigan’s immense size lends itself to stories of danger and mystery. Some are true, and some are not.

Today, we’re investigating the most dangerous creatures in Lake Michigan. Should you be concerned about swimming or boating there?

Let’s find out!

Sea Lamprey

The Sea Lamprey must be the scariest-looking of all the dangerous creatures in Lake Michigan. It has an eel-like body, and its mouth is large and round with numerous rows of sharp teeth.

It’s a parasite that clamps onto its prey with those teeth, then uses its rough tongue to create a hole in the skin to get at the blood and other fluids. It’ll often kill any fish it latches onto.

That said, the Sea Lamprey’s only danger to people hanging out on or in Lake Michigan is that it’s invasive and is devastating the other fish. As with most invasive creatures, it has only a couple of predators within the lake, can reproduce quickly, and thrives in the Lake Michigan climate.

The adults are slow-moving. However, the lamprey are difficult to eradicate because the larval forms dig into the sediment and can live there for up to ten years.

dangerous creatures in lake michigan. snapping turtle
While most Lake Michigan creatures look scary, they generally aren’t aggressive toward people.

Snapping Turtle

Snapping turtles do live in and around Lake Michigan and are native to the area. Like most animals, they will bite if they feel the need to defend themselves. But they aren’t aggressive toward people without provocation.

Steer clear of them, and you’ll be fine. Try to pet one, and you may lose a few fingers.

Pro Tip: Don’t let the creatures of Lake Michigan stop you from some amazing campgrounds. We explored the 7 Best Campgrounds on Lake Michigan.


Cyanobacteria is certainly the most insidious of all the Lake Michigan dangers. Also known as blue-green algae, it’s common in many lakes and waterways around the world. Many are harmless, but some of the species can create toxins that make people and animals sick.

The algal organisms bloom – rapidly reproduce – when the water contains a large amount of their favorite nutrients, the temperature becomes warm, and the water has low movement.

The higher levels of nutrients usually come from water pollutants such as fertilizers, manure, and malfunctioning septic tanks. This blooming is when the toxins are produced.

dangerous creatures in lake michigan, cyanobacteria
Cyanobacteria looks like blue paint on the surface of a lake.

Cyanotoxins released from these blooms can cause rashes, skin blisters, and breathing difficulties just by coming into contact with your skin. If you swallow any water with these toxins in it, you could end up with gastrointestinal or even neurotoxic issues including vomiting, numbness, dizziness, and difficulty breathing.

Taking in enough contaminated water can damager your liver or kidneys.

Even boating or jet skiing through cyanotoxic water can cause health problems. So, if you see signs saying the beach and water are closed because of algal blooms, do yourself and your pets a favor and find something else to do.

Unfortunately, these blooms can last from a few days to a few weeks.

Land Animals

The animals surrounding Lake Michigan may be more dangerous than anything in the water, except the cyanobacteria. The area contains highly venomous spiders such as the brown recluse and black widow. Mosquitos and black-legged ticks carry diseases that can leave you battling illness for the rest of your life.

You could also run into a rattlesnake, black bear, or rarely, a gray wolf.

Unfounded Claims of Dangerous Creatures in Lake Michigan

Some article headlines sensationalize creatures such as pirhanna showing up in Lake Michigan only to quietly state at the end that they haven’t actually been found there. Let’s take a look at some of these.

The Northern Snakehead Fish is probably the creepiest of all because it can wiggle-walk its way across the land to a new lake when it runs out of food in one. The Snakehead is a non-native, invasive fish whose only predators in the U.S. are anglers. Although, it’s not a fish most would want to catch. They can grow up to 33 inches long and have sharp teeth that can and do pierce human skin.

The Northern Snakehead isn’t aggressive toward people but will bite if they feel threatened. Their real danger is that they destroy native species and, therefore ecosystems. What’s more, is that one female can lay up to 150,000 eggs each year. Once they’ve found a home, they’re difficult to remove.

dangerous creatures in lake michigan
Lake Michigan is home to many creepy fish, snakes, and other creatures.

Pirhanna and Pacu are also fish with sharp teeth that have been known to bite people. However, pirhanna haven’t been seen in any Michigan areas. Pacu, on the other hand, have been seen in southeastern Michigan. No one has reported seeing either fish in Lake Michigan though.

Bull Sharks can and do survive in freshwater for quite a while, and reports have shown them to be several miles upriver from their normal habitat. In 1955, a young boy was reportedly bitten by a shark in the lake, and people have made a couple of other reports of seeing sharks there.

However, the evidence that they’re in Lake Michigan is nonexistent or, in one case, questionable. In addition, scientists say that Lake Michigan’s waters are too cold for sharks and the odds are very slim that one would be able to survive there.

dangerous creatures in lake Michigan
Be careful when around the creatures of Lake Michigan, but don’t let that stop you from enjoying this beautiful waterway.

Pro Tip: After searching for creepy creatures in Lake Michigan, explore these 7 Amazing Waterfalls in Michigan.

Lake Michigan Creatures Aren’t All That Dangerous

Spending time in Lake Michigan doesn’t seem to be any more dangerous than most other waterways, maybe even less so than in other parts of the country.

However, as with any area you’re visiting, know what dangerous animals are around and how to avoid a confrontation if you come across one. Have you seen any dangerous creatures in or around Lake Michigan?

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  1. Kyle & Olivia Brady says:

    I thought you were unsunscribing