Have you ever wondered just how many species of leech exist on this planet? Well, the answer might surprise you. There are roughly 480 species of leeches that inhabit freshwater areas and around 100 species that live in the marine. That’s a lot of slimy little bloodsuckers!
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And believe it or not, there are plenty of leech-infested lakes in the United States where these creatures can be found in abundance. With over 250 lakes throughout the country, it’s important to know which ones have the highest population of these parasites if you plan on taking a dip.
Lucky for you, this guide will provide all the information you need to avoid those pesky critters.
Leech Teemed Lakes:
As scary as the thought of leeches may be, not all of them are harmful or carry diseases. Leeches are often found in water, especially in the shallow shoreline of lakes. They are similar to earthworms in appearance and behaviour. While some leeches do feed on blood, not every leech will suck your blood. It’s important to note that the lakes with an abundance of leeches are not limited. For those with a phobia of parasites or worms, the presence of leeches can be troublesome and dangerous.Â

The 7 Most Leech-Infested Lakes In The United States
Leeches, also known as segmented worms, are a common sight in lakes throughout the United States. While fascinating creatures from a biological standpoint, these bloodsucking parasites can quickly turn a relaxing day at the lake into a nightmare. Swimming in heavily infested lakes can be like ringing the dinner bell for leech species, so it’s important to exercise caution when entering these waters.
Lakes in the United States plagued by an abundance of leeches are;
- Lake Gaston
- Lake Lanier
- Lake Michigan
- Lake Erie
- Lake George
- Lake Tahoe
- New Hampshire Lakes
#1 Lake Gaston
Lake Gaston is a true gem among clean water lakes, spanning over 20,000 acres and stretching for about 32 miles in length. It is flanked on either side by the Gaston and Kerr dams, making it a picturesque location for fishing enthusiasts.
While the leech population might be on the rise in this pristine water body, there are plenty of other game fish that can be found in abundance. Largemouth Bass, catfish, sunfish, crappie, rockfish, and striped bass are just some of the attractions that make Lake Gaston an angler’s paradise.
So if you’re looking for some cultural activities to enjoy among the water and wilderness, Lake Gaston has plenty to offer in addition to its leeches and bass, making it a must-visit location for nature lovers and fishing enthusiasts alike.
#2 Lake Lanier
Nestled in the heart of Georgia, Lake Lanier is a breathtaking sight to see. Its vast surface, spanning over 37,000 acres, beckons for adventure and exploration. But before diving in, visitors should be aware of its inhabitants. Lake Lanier is home to a large population of leeches.
While not all of them are harmful, some can cause a disturbance, making swimming less desirable to those who are leech-phobic. Despite this, the people of Lake Lanier have learned to coexist with these slimy creatures, considering them as tenants of the lake.
#3 Lake Michigan
Lake Michigan, located along the shoreline near Indiana Dunes National Park, is one of the five great lakes in the United States. It ranks as the second-largest lake by volume and the third-largest by surface area among the great lakes. With its remarkable features and attractions, many people consider Lake Michigan an ideal destination for their trips.
Within Lake Michigan, various species of aquatic organisms thrive, including several types of leeches. However, compared to other lakes in the United States, the leech population in Lake Michigan is relatively low. Scientists who regularly examine fish in the lake have found that only a small percentage of them carry barnacles.
Nevertheless, in areas of Lake Michigan where fish populations are scarce, the number of leeches tends to be higher. Although a few residents have reported leeches attaching to their feet, the Department of Conservation has received only limited complaints. To date, there have been no reports of significant harm or infection caused by these creatures.
#4 Lake Erie
These rocks provide ideal habitats for leeches to inhabit, I’m certain!
Certain types of leeches are increasingly prevalent in the stagnant waters of Lake Erie. What makes these leeches unique in Lake Erie is their inability to swim, leading them to reside in muddy areas. They often pose a challenge for anglers in the region.
When the water levels are low, fish tend to stay closer to the lakebed, exacerbating the leech problem. Leeches attach themselves to walleye, seeking a blood meal. However, they do not harm the walleye, and consuming a walleye that had a leech attached for blood-sucking does not pose any health risks to humans.
The specific species of leeches found in Lake Erie have not been officially identified yet. These segmented worms contribute to the transmission of diseases within the Lake Erie watershed.

#5 Lake George
There have been a few instances where people have been bitten by leeches at this particular lake.
Lake George, also known as Lake Welaka, is a renowned body of shallow brackish water situated in Florida, United States. This expansive lake covers an impressive surface area of 46,000 acres.
Lake George is home to a diverse range of marine organisms, including various species of leeches. These leeches thrive in the lake due to its shallow and freshwater characteristics. They can be found beneath rocks and at the lake’s bottom.
Unfortunately, there have been reported cases of leech bites at Lake George, which can be somewhat concerning. Many individuals have experienced allergic reactions and shock, while others have managed to remove the leech without requiring medical attention.
If you ever have the opportunity to visit Lake George, it is important to remain vigilant for the presence of snakes in the surrounding areas of the lake.
In addition to leeches, you may also encounter different aquatic worms, pouch snails, and midge flies within Lake George. Fishing, boating, and hiking are among the most popular activities enjoyed by visitors to Lake George.
#6 Lake Tahoe
Lake Tahoe, situated in the United States, holds such a stunning charm that people are willing to brave the leeches to experience its beauty. The lake is a magnificent freshwater behemoth surrounded by the breathtaking Sierra Nevada hills, encompassing everything from ski resorts to picturesque beaches.
The crystal clear water of the lake is alluring, beckoning thousands of visitors every year to soak in its depths and indulge in activities like swimming, fishing, and boating. Scuba diving is also a favoured pastime here, thanks to the lake’s ample depth.
While it’s true that Lake Tahoe is home to many leech species, they pose no serious threat to humans. Visitors, however, may find these pesky little creatures a nuisance. Despite this, the combination of pristine water and stunning surroundings ensures that Lake Tahoe remains a prominent attraction.

#7 New Hampshire Lakes
Nestled in the heart of New Hampshire lies Conway Lake, a stunning body of water that’s a favourite among locals and tourists alike. Unlike many of the state’s lakes, Conway Lake manages to evade a frozen fate during the winter months, making it a year-round destination.
However, like many New Hampshire lakes, the waters of Conway Lake are home to some nocturnal leeches. Visitors should be wary of these creatures, as they have a tendency to cling to swimmers’ bodies. Despite the presence of leeches, the water in Conway Lake is still clean and pure, though it is not immune to threats from invasive species, polluted runoff, and other environmental factors.
But despite these challenges, Conway Lake remains a place of natural beauty and tranquillity, offering visitors a glimpse of the untamed wilderness that lies just beyond the horizon.
Bloodsuckers Other Than Leeches In United States Great Lakes
The great lakes of the United States are not only host to the infamous leeches but also to another group of dangerous bloodsuckers known as lampreys. Lampreys are infamous for their preference for cold blood and their habit of feeding on fish, which makes them particularly detrimental to various fisheries in the great lakes.
The cisco population in lake trout was greatly reduced because of the lampreys’ insatiable hunger. It is worth noting that lampreys are actually ocean creatures, and their presence in the great lakes is harmful to the ecosystem and local habitat. Swimmers should also beware, as lampreys can attach to them as well.

Lampreys In Lake Champlain:
Leeches are not the only organisms that engage in bloodsucking. There are various other bloodsuckers, such as lampreys.
Lake Champlain, renowned for hosting the world’s oldest fossil reefs, is a freshwater lake located in the United States. Lampreys, which are similar to leeches in their bloodsucking behaviour, abound in Lake Champlain.
Lampreys are a species of fish equipped with suction cups and teeth that aid in their attachment to host bodies. They lack jaws and should not be mistaken for eels. Lampreys entered Lake Champlain in the 1800s through the Hudson Canal.
Lamprey bites are considered dangerous as they cause pain. Once someone becomes a lamprey’s prey, there is a significant risk of developing infections that are not associated with leeches.
Many ecologists recommend preventing the establishment of canals connecting the Great Lakes to inland lakes to keep these jawless vertebrates away from inland water bodies.
Role Of Leeches In Lake
Leeches, despite their reputation for being annoying or frightening, are actually vital to the functioning of ecosystems. These slimy creatures play an important role in the food chain, serving as parasites, vectors, prey, and predators for many other organisms.
While some may be put off by the sight of a leech attached to their skin, it’s important to remember that these creatures are not typically harmful, unlike their tropical counterparts. In fact, in many lakes around the world, leeches are a crucial part of the natural environment, helping to maintain balance and support the overall health of the ecosystem.
While some species of leech may be considered invasive or troublesome, the native species are an important part of the food web and should be respected for their contributions to the natural world.

Leech Ideal Place In Lakes
Leeches, those slimy invertebrates that many people find revolting, are often associated with lakes. However, contrary to popular belief, leeches don’t live throughout the lake. In fact, they are most commonly found in shallow water near the shorelines and rocks.
They are also known to inhabit those areas inside the lake where there are organic debris, weeds, and submerged branches that provide hiding or attachment. While leeches are generally more prevalent in freshwater habitats, some species can tolerate saltwater too.
So, the next time you go for a swim in a lake, don’t worry too much about encountering these creepy crawlies. They may be lurking around, but as long as you stick to deeper waters, the chances of running into them are pretty slim.
How To Avoid Leeches In Lakes?
There are specific strategies and techniques to avoid encountering leeches in lakes. As mentioned earlier, leeches tend to thrive in shallow water, so swimming in such areas is essentially an open invitation for these bloodsuckers. On the other hand, leeches are typically absent in deeper water, making it a safer option for swimming without leech-related concerns.
- Staying away from shorelines can also help minimize the chances of leeches attaching to your body.
- It’s worth noting that leeches are generally considered harmless, as they have not posed significant issues for swimmers thus far. As a result, lake management in the United States has not implemented stringent measures to address leech-related concerns.
- Bait trapping is an effective method to prevent leeches from latching onto the body.
- Along lake shorelines, leeches are commonly found under stones, sticks, and other debris. Regularly cleaning the shoreline by removing organic debris can significantly reduce the leech population in the area.
What To Do If You Get A Leech?
Swimming in a lake is an enjoyable activity, but encountering leeches can be a scary experience. If you find a leech on your skin, do not panic. The thinner end of the leech body is where its mouth is located. It’s important to first locate the leech’s mouth before attempting to remove it from your skin.
To remove it, place your finger near the leech’s mouth and slide your fingernail towards it. Push the leech’s mouth sideways to ensure it doesn’t get stuck in your skin. After the leech is removed, be sure to disinfect the affected area and cover it up. Knowing what to do in this situation can help keep your swim in the lake enjoyable.
Final Words
Leeches are fascinating creatures that hold a significant place in the aquatic food web. However, most people are not thrilled about encountering them while swimming in the lakes. In this write-up, we have highlighted the top seven leech-infested lakes in the United States. Not all leeches suck blood, and not all of them pose a risk of infection.
These creatures typically inhabit shallow water and shorelines of freshwater, making these spots their ideal habitat. As such, they can often be found hiding and attaching themselves to organic debris within the lakes, such as branches and plants. So, if you plan on swimming in any of the seven lakes mentioned in this article, it’s worth knowing about the potential encounters with leeches.
Reference:
- https://www.maine.gov/dep/water/lakes/leech.html
- https://www.des.nh.gov/sites/g/files/ehbemt341/files/documents/2020-01/bb-10.pdf
- https://www.adirondackdailyenterprise.com/news/local-news/2018/06/while-gross-leeches-arent-actually-dangerous/

Zahra Makda
Growing up enjoying the beauty of my village, a good passion for nature developed in me from childhood. Following my passion for the natural world, I have chosen zoology for my graduation, during my undergraduate degree, I participated in many nature trails, bird watching, rescues, training for wildlife conservation, workshop, and seminars on biodiversity. I have a keen interest in invertebrate biology, herpetology, and ornithology. Primary interests include studies on taxonomy, ecology, habitat and behavior.