This is the whole process of a razor clam digging a hole. It happened at low tide. The razor clam was accidentally washed out by the sea water and exposed on the beach. In order to avoid predators, it had to bury itself in the sand again.
Bivalves have strong defense capabilities, and they are basically filter feeders, which means that they can avoid predators and solve feeding problems without actively moving themselves.
This leaves most bivalves with little mobility or even almost no active mobility.
Razor clams are an exception;They are one of the fastest moving bivalves, especially for digging, they can dig downward at a speed of 23 centimeters per minute.
Both ends of the razor clam will expand and contract outwards. In the video, the first thing to squirm and dig into the sand is the feet.The razor clam's foot muscles are very powerful, allowing them to dig.
They have two water pipes on their heads, one is used to absorb water, and the other is used to discharge water. The suction pipe will suck in seawater and food together, and then filter out the food, while the residue will be discharged through the outlet pipe. The one that spits out sediment in the video is their outlet pipe.
In addition to keeping the razor clams safe when the tide goes out, digging also helps them anchor themselves in the water when the tide comes in, making it easier for them to feed themselves.
But after the tide rises, they have to do one more thing, which is to lift their own water pipes out of the sand - ensuring that the two water pipes must be exposed for eating and excretion.
For bivalves, rising in the mud is much more difficult than digging, but razor clams have foot holes for spraying water, and they can move themselves upward through the reaction force of the water spray.
When the tide goes out, there is usually a feast for seabirds and other predators. Like people chasing the sea, these predators wait there early, eager to enjoy the delicacies brought by the power of the tide.
As for the fish and shellfish that were stranded on the beach, they could only sit and wait for death, and the people who rushed to the sea picked them up casually with buckets, without any effort.
Razor clams are one of the few beach delicacies that have the ability to escape predators.
However, when they encountered unruly humans, they could tell they were hiding inside just through the entrance of the cave, and then used highly concentrated salt water to force them out of the cave. Although it took some effort, they were still able to be caught.