Leeches are commonly found in freshwater areas, such as lakes, springs, and slow streams. However, there are about 480 species, some of which also like to live in marshes and other bodies of water.

Some types of leeches are straight-up predators, and others eat organic debris, but most of us know the kind that is parasitic. These aquatic leeches usually feed on the blood of birds, amphibians, and fish or eat the worms and larvae that come their way.

So you have to be careful when stepping into your local water body. Even if that one is clear of leeches, there are at least seven leech-infested lakes in the United States. They lurk in the area about 2 meters below the surface of the water, safe from all wave action.

Trust us; you don’t want to invite these spicy worms to feast on your blood. Here are the top 7 US lakes you don’t want to swim in:

Steer Clear of These Leech-Infested Lakes!

1. Lake Gaston

Lake Gaston is nearly 32 miles long and spread over 20,000 acres of pristine land. The sheer size of it makes it the perfect location for two dams – it is bounded by Kerr and Gasto dams.

Moreover, it is one of the cleanest lakes in all of the United States, so naturally, you wouldn’t even know what lurks right under its surface.

This lake also has a large population of largemouth bass, catfish, crappie, rockfish and many other types of game fish, attracting amateur and experienced fishermen. While fishing should be fine, don’t make the mistake of taking a dip in these waters. And don’t let its clean and pristine appearance fool you since it is one of the most leech-infested lakes in the country.

But these leeches prefer to live in shallow protected areas, i.e., places with plenty of aquatic weeds and tree branches to give them cover. So, if you must go swimming, stick to deeper waters that’s free of plants and debris, etc.

2. Lake Lanier

If you have Scoleciphobia (fear of worms), hold on to your heart because Lake Lanier is the stuff your nightmares are made of.

Lake Lanier is a very impressive 156 feet deep and covers a surface area of 37,000 acres in Georgia. The depths are the perfect dwelling place for thousands of leeches. And while the location is picturesque and often considered a perfect tourist destination, know that it is infested with several species of leeches. And some of these can get clingy and cause disturbance for those who get into these waters. So it’s best to avoid swimming.

In fact, just stay inside your boat.

3. Lake Erie

While the beach areas of Lake Erie are safe to swim in, we can’t say the same for deeper waters.

It is one of the largest freshwater fisheries and has the biggest production and biological diversity among the world’s water bodies. This doesn’t just mean fish but also leeches.

But what’s unique about the leeches in Lake Erie is that they can’t swim, so they are prominently found in the muddy shallow waters around the lake. And that’s bad news for anglers. The leeches often get attached to the walleye in these waters to fulfil their need for blood.

But don’t worry, if you do eat this prized fish that was once fed on by a leech, you won’t get a disease or anything. It causes absolutely no issues in humans.

Just which species of leech is found in Lake Erie remains a mystery of sorts since scientists can’t figure out the answer, and they have very little data on this topic.

4. Lake Michigan

We are slowly moving to the big leagues now.

Lake Michigan is counted among the five great lakes of the United States, and for good reason. It isn’t just great by name but the second biggest lake in the entire country by volume and the third biggest by surface area, with a maximum depth of 923 feet. That’s a lot of water!

It is situated near the Indiana Dunes National Park and of the best places for a day trip for visitors to the area.

Interestingly, Lake Michigan doesn’t just have a few species of leeches, but it’s also home to several other marine organisms. It’s big enough to house all kinds of things, and that explains why the number of leeches in there is smaller compared to other lakes across the US. Scientists have observed very few fishes here with barnacles attached to them, clearly showing that there aren’t enough blood-sucking leches here to bother the fish.

However, there are some parts of lake Michigan that have a bigger population of these bloodsuckers. We suggest you don’t try your luck by getting into the waters. Locals routinely report coming out of the lake with leeches stuck to their feet. But there has been no long-term damage, harm or infections so far.

5. Lake George

This shallow freshwater lake is also famously known as Lake Welaka, and has a vast surface area of 45,000 acres.

It is widely known for its biodiversity as it is home to various macroinvertebrates such as black flies, midge flies, several different types of snails, aquatic worms and, of course, leeches.

But don’t let that fool you. It is quite safe to swim in Lake George. In fact, it is one of the cleanest lakes and offers 32 miles of exquisite wide bays, many quiet coves and wooded islands that you can fall in love with.

Sure, there have been some reports of leech bites on this lake, but these bloodsuckers usually stay at the bottom of the lake or under the rocks around the lake. The people who do get bit by leeches experience mild allergic reactions or shock; many don’t even need any medical care once the leech has been removed.

But leeches really aren’t the biggest problem here. You should keep an eye out for the many snakes that are present in and around Lake George.

6. New Hampshire Lakes

New Hampshire has nearly 1000 lakes – all shapes and sizes, ponds, rivers and streams. There’s a lot of water here, and most of it freezes over in winter.

Also, leeches are present in most of these New Hampshire lakes. But you won’t see them during the day because they are nocturnal, i.e., active only at night. And when you go swimming in these waters around that time, chances are high that you’ll come out with several blood suckers attached to you.

And get attached, they will. The bloodsuckers here prefer to feed on warm-blooded animals, and that includes humans.

The water in these lakes is usually clean and pristine. But things are changing for New Hampshire lakes as new and invasive species make their way here, while runoff and polluted water make things difficult for everyone.

7. Lake Tahoe

As one of the most breathtakingly beautiful places in all of North America, Lake Tahoe invites you to take a dip the second you lay your eyes on it.

Decline that invitation!

This lake is over a mile in depth, and it is said to be over 2 million years old. And as you can guess, many secrets lurk in its depths.

Still, it has become quite the destination for people who love all the fishing, hiking and jet skiing opportunities it offers. But swimming in there may not be such a good idea.

The pesky leeches inhabit its reservoirs and waterways, and while they aren’t particularly destructive and harmful to humans, their bits can result in allergic reactions.

Officials don’t recommend you swim on Lake Tahoe, specially Spooner Lake, which is an artificial reservoir inside the Lake Tahoe-Nevada state part. But by all means, take a boat and go sightseeing. It really is lovely.

Snakes are another issue. But the ski resorts and beaches here are relatively free of them.

What Do Leeches Do In US Lakes Anyway?

The fact of the matter is that leeches are important for the lake ecosystems.

Yes, they are pesky, irritating and even downright scary at times, but they are a vital link in the food chain. Many species of fish feed on them, and they are parasites and predators for many other kinds of parasites and marine animals.

Their presence keeps the population of potentially dangerous invasive species at a minimum.

So, while they might keep you from swimming in your favorite lake, chances are that their presence plays a role in keeping the lake healthy and stocked with all kinds of fish.

The good news is that as long as you are careful, and understand the lake ecosystem and leeches, you can still enjoy swimming in it. So, here’s what you need to know: leeches aren’t found uniformly throughout a lake. Instead, they reside in shallow waters, rocky areas and shorelines.

Moreover, leech species do not like to live in deep waters. And, if they do, the area likely has a lot of weeds, broken and submerged branches and plenty of organic debris where they can hide.

And finally, just because we only counted the freshwater lakes in the US, doesn’t mean you will never come across saltwater leeches. A few species dwell in saltwater bodies as well.

In Conclusion

Leeches are freeloaders looking for their next blood meal. Don’t let it be you.

The good news is that they aren’t particularly predatory towards humans. That’s is unless a particularly juicy opportunity presents itself. Eww.

But creepy as that may be, leeches are not all bad. Not all species suck blood or cause infections. And most of them prefer to just chill under rocks, sticks and weeds. Besides, leeches can easily be spotted in most lakes because their ideal place is in shorelines and shallow waters. So you can steer clear of them.

Still, no one wants to think about having leeches stuck to their hands, feet or legs, casually sucking the blood out of them. And this image can be particularly painful if you have a fear of worms and worm-like creatures. It’s best not to get into the waters if you do visit the leech-infested lakes on our list. And if you must, keep away from the shorelines.