Are Freshwater Clams Edible or Are They Toxic


Nature is filled with an abundance of food sources for whenever you’re in the great outdoors. However, the problem is that there are certain plants or animals that you cannot eat because they aren’t edible or possibly even poisonous.

Whenever I camp by a river or lake, aside from fish, I sometimes see freshwater clams. Over time, I’ve started to ask myself, are freshwater clams edible? Or are they toxic?

Well, if you’re thinking about grabbing some of those suckers out from the water on your next adventure, there are some things you should know about them first!


Clams are a type of bivalve mollusks. They are often found buried in the sands of the ocean floor, although, some can also be found in bodies of freshwater such as rivers or lakes.

Clams are very popular as seafood dishes due to its light taste and perfect pairing with other dishes and ingredients such as cheese, pasta, rice, soups, and so much more.

While the most popular type of clams are those that are found in the ocean, the ones found in freshwater are often questioned for their edibility. But why?



The reason why people often wonder if freshwater clams are actually edible is because clams are “filter feeders”. This means that they are constantly ingesting the water around them while filtering out any substances found there, including pollutants and toxins.

So, the answer is, yes, they can be toxic if the water you are getting them from is not clean. But in the same sense, freshwater clams can be edible, as long as you ensure they are coming from a clean source of water.

If you notice any pollutants around the area or in the water itself, it’s better to not take your chances.


The question now is – what do you do with the clams once you’ve caught them (from a fresh and clean source I’m hoping)? You’ll need to purge and prep them before you can begin to cook them.

What “purging” simply means is that you allow the clams some time to get rid of any substances they may have ingested, such as sand. How to do this is to simply place the clams into a large bowl and submerge them in clean water. Leave them there for about 20 minutes to 1 hour.

What this does is it gets the clams to open up and start filtering all the substances they’ve previously ingested. After the 20 minutes to 1 hour, you might even notice some sand or other debris in the bottom of the bowl.

Rinse the clams out thoroughly, and if you feel they aren’t clean enough, you can repeat this process another time.

NOTE: When purging freshwater clams, DO NOT add salt. Freshwater clams do not like salt and they will close up tightly as to not let any saltwater in.


Even if you’re in the outdoors, it’s still important to make sure that the food you eat is clean. After you’ve purged your clams, you need to clean their exterior. You can do this by using a brush or a washcloth to clean away any dirt or debris that have crusted in the exterior.

If you want to read a little bit more information on purging and cleaning clams, you can visit Weekend Notes and read their article on purging Freshwater Mussels. 



While you’re cleaning your clams or even after the purging process, you need to discard clams that are no longer alive, or else if you eat them, you may feel sick.

You want to look for clams that are tightly shut. If they are open, give them a gentle tap. If they don’t close or move, they are dead, so discard them. Do this for each clam to ensure that they are fresh and still alive.

Clams that are floating in the water are dead as well. They float because they release a gas when they die. So be sure to get rid of those ones as well. If there are any clams with broken shells or shells with holes in them, discard those too.


It’s important to note that freshwater clams may be endangered in certain parts of North America. Some states even have a ban on harvesting freshwater mussels.

In Wisconsin, for example, commercial clamming is not allowed, and it is actually illegal for an individual to harvest live clams from the waters of Wisconsin. If you are from Wisconsin, you can read about it here.

In Indiana, biologists from Wildlife Diversity compiled a long list of freshwater clams and marked them as either state endangered (SE), special concern (SC), federal endangered (FE), federal threatened (FT), federal candidate (FC), extirpated (EX), or exotic (X).

If you are from Indiana, please do support their conservation efforts for endangered species. You can read about it here.



So remember, freshwater clams are edible, but they can also be toxic. Be sure the water and all surrounding areas are clean. If possible, ask locals or tour guides if it is safe to eat the clams in the area.

Remember to also do your research beforehand on rules and regulations of the specific place you are visiting. Cooking fresh clams while you’re outdoors is a great experience – just be sure you do it safely!


The author Joshua

Hi, my name is Joshua. founder of MadOutdoorist.Com, I was born into a lovely family that loves nature and adventure. My goal at Mad Outdoorist is to provide you with all the information you need for a successful out-of-city adventure. It is my desire to encourage you to push beyond any physical limit you may have.

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