Clams are a favorite food source for many fish species. Their soft bodies protected by hard shells make them an ideal high-protein meal. But which fish actually eat clams? And how do they get past the clam’s sturdy outer shell to access the soft flesh inside?
If you’re short on time, here’s a quick answer to your question: Many bottom-dwelling fish like flounder, black drum, sheepshead, and cunner eat clams. They use their powerful jaws and teeth to crush the clam shells. Fish like pufferfish can inflate themselves to wedge open the shells.
Fish Species that Eat Clams
Flounder
Flounder are a type of flatfish that spend most of their time camouflaged on the ocean floor. They have excellent vision and actively hunt for food, including clams. Flounder use their asymmetric mouth to suck in prey from the sand.
Their strong jaws allow them to crush the shells of small clams and get to the meat inside. Some species such as winter flounder are especially adept at finding and eating hard-shelled clams like quahogs.
Black Drum
The black drum is another bottom-dwelling fish that feeds on clams. These fish use their large, powerful jaws to crush clam shells. Their strong pharyngeal teeth complete the job of grinding the shells into small pieces so the drum can digest the soft clam body.
Black drum often root around sandy or muddy areas looking for clams and other mollusks to eat. They will also scavenge dead clams that have washed up on the shore.
Sheepshead
Sheepshead get their name from their impressive set of human-like teeth. They use their strong incisors to pry open clams, oysters, and mussels. Once the shell is cracked, they use their powerful molars in the back of their mouths to crush the shell and expose the meaty interior.
Sheepshead often feed on clams around rock jetties, reefs, and pilings in estuaries and near shore coastal waters.
Cunner
The cunner is a small fish in the wrasse family that inhabits northern coastal regions. Cunners are well adapted for feeding on shelled animals like clams, mussels, and barnacles. Their protrusible jaws allow them to reach into cracks and crevices to pick out hiding clams.
They also have strong teeth in their throats for crunching the shells and accessing the meat inside. Cunners are resident fish that stay in a small home territory, giving them intimate knowledge of where to find clams to eat.
Pufferfish
Although small, pufferfish have immensely powerful jaws and teeth that can crack thick clam shells with ease. They use their beak-like mouths to break open the shell and raspy teeth to grind up the interior.
Some species even pile clams into a nest and return periodically to work on cracking them open. Pufferfish may rarely eat the meat, instead using the cracked shells to access barnacles, crabs and shrimp that have colonized the interior of the dead clams.
Their ability to eat rock-hard clams gives pufferfish access to prey other fish can’t reach.
How Fish Eat Clams
Fish have developed clever ways of getting to the tasty morsels inside clam shells. Their techniques include crushing the shell, prying the shells apart, or sucking the clam out of its protective casing.
Crushing the Shell
Fish like black drum use their powerful jaws and strong teeth to simply crunch through clam shells. They swallow the broken fragments along with the clam inside. Studies show that the black drum’s bite force can reach over 1,000 pounds per square inch, easily breaking through clam shells (Source).
Other fish like the calico crab use their claws like nutcrackers to crush the clam shell. Their claws can apply extreme pressure of up to 60 pounds per square inch to break the shell into pieces (Source).
Prying the Shells Apart
Resourceful fish like rays use their flat teeth to grip and peel open clam shells. Species like the cownose ray use series of pharyngeal teeth to grind against the clam shell until it pops open.
Crabs also use their claws to prise open clam shells. They grip the two valve edges and apply steady force, working the shells apart little by little. Studies found that crabs can generate sufficient mechanical force to open a clam shell in just over a minute (Source).
Sucking the Clam Out
Octopuses and squids are masters of hunting shelled animals like clams. They use their sharp beak to pierce through one side of the clam shell. Then they insert their tongue-like radula inside and scrape the clam meat off.
They also use their funnel to blow jets of water into cracks in the shell. The powerful current forces the valves open, allowing them to suck out the soft body inside using their siphon. Slow-motion videos show octopuses can slurp up clams in less than two minutes through this technique (Source).
So whether it’s using brute strength, manual dexterity, or hydrodynamics, fish and marine creatures have evolved all kinds of methods to get past the clam’s hard shells. Their survival depends on accessing this nutritious prey item, driving the development of specialized feeding strategies over countless generations.
Where Fish Find Clams
Sandy Bottoms
Sandy bottoms are a prime habitat for many clam species like quahogs, soft-shell clams, and razor clams. The sandy or muddy substrate allows clams to easily burrow into the seabed and hide from predators.
Fish like striped bass, black drum, and flounder often cruise along sandy shallows looking for signs of buried clams. They use their keen senses of smell and sight to detect hidden clams. According to a 2019 study, flounder and black drum can find buried clams with up to 92% accuracy just by detecting signs of their presence.
Seagrass Beds
Seagrass beds are an excellent habitat for many clam species like hard clams, cockles, and bean clams. The roots and blades of seagrass plants help anchor clams in place and provide protection. Fish like black drum, sheepshead, and permit forage through the grasses nibbling on clams.
According to the Florida Fish and Wildlife Commission, sheepshead have specially adapted incisor teeth for prying open clam shells. Seagrass beds in estuaries can contain up to 200 clams per square meter, providing a reliable food source for hungry fish.
Rocky Coastlines
Rocky intertidal zones harbor many edible clam species like Pacific littleneck clams, soft-shell clams, and mussels. Fish like black rockfish, wolf eels, and cabezon scour the rocky substrate looking for exposed clams to eat.
According to a National Oceanic and Atmospheric Administration report, wolf eels can use their strong jaws and teeth to crush thick mussel and clam shells. Rocky coastlines provide ample crevices and holes for clams to hide in, but savvy predators still manage to pluck them from their stony shelters.
Estuaries and Bays
Estuaries and bays provide ideal habitat for clams like eastern oysters, soft-shell clams, and hard clams. Fish like striped bass, blue crabs, and pufferfish migrate into these areas to feast on bountiful clam beds.
According to a Florida Department of Environmental Protection report, a single adult pufferfish can eat over 100 small hard clams per day. The sheltered waters of estuaries allow clams to achieve high densities, making them an easy target for hungry fish.
Their predation helps maintain balance in the estuary ecosystem.
When Fish Eat Clams
Low Tide
Low tide presents a prime opportunity for fish to feast on clams. As the water recedes, clams are exposed and more vulnerable to predation. Fish like black drum, red drum, striped bass, and flounder will patrol the shallow waters looking for an easy meal.
Using their hard, bony mouth plates, they are able to crush the shells and access the soft meat inside. Studies show that during low tide periods, predation on clams increases significantly.
According to research from the University of South Alabama (1), areas with greater tidal fluctuations see the most clam predation. Intertidal zones become a buffet for opportunistic fish when the tide goes out. They can leisurely swim about and dine on clams without fear of larger predators.
This gives small fish a window of opportunity to enjoy clams before the tide comes back in.
Spawning Seasons
Fish are especially motivated to eat clams during spawning seasons. Clams are a great source of protein and nutrients that fish need to develop strong eggs and sperm. For example, striped bass gorge on clams in estuaries before migrating upstream to spawn in the spring.
The protein in clams helps fuel their long journey and aids in reproductive success.
Some key spawning times when predation is highest include:
- Striped bass – April to June
- Flounder – October to December
- Black drum – February to April
Researchers in Virginia found striped bass nearly doubled their clam consumption in April compared to other months (2). By targeting clams, fish can quickly build up energy reserves to improve reproductive fitness.
Night Hunting
Many fish capitalize on the cover of darkness to hunt clams. Under the veil of night, fish can swim right over clam beds and attack without the prey detecting them. Species like black drum use their keen sense of smell to root clams out of the sediment.
Fish may also take advantage of clams that are actively feeding at night. As clams siphon water to feed on plankton, fish can grab the exposed siphons. One study in North Carolina found up to 61% of clams exhibit siphon nipping injuries from nighttime predation (3).
Nighttime clam fishing allows fish to avoid competition from visual hunters like blue crabs and seabirds. Darkness provides the perfect cover and minimizes their own chances of ending up as prey. The ocean truly comes alive around clam beds once the sun goes down.
Conclusion
Clams are an abundant and nutritious food source for many fish species. Bottom-feeders like flounder and pufferfish have evolved adaptions to prey on hard-shelled clams. Understanding when, where, and how different fish eat clams provides insights into aquatic food chains and ecosystems.
