A Brief Guide to Clam Reproduction
Most people are understandably confused when it comes to clam reproduction. With no seemingly discernable sexual organs, and since their lives are spent attached to a closed shell, this is truly one of the great mysteries of the sea. Thanks to scientific research, this mystery can be unraveled and people can now understand this puzzling process.
The sexual identity of clams is not as easy as simply determining whether one is a male or a female. Sex can depend on the species of clam and what stage of life the individual clam is currently in. In some cases, clams may be hermaphroditic, or both sexes.
For instance, hard shell clams are born as males, but later become female as they grow and mature. In order for this species to reproduce, a younger clam must fertilize a much older one’s eggs. This can be difficult to do depending on location and body of water.
Assuming that the right species and sexes are present, clam reproduction takes place very similarly to most other creature’s reproduction. Female eggs are fertilized by male sex cells. The mechanics behind this are still puzzling to many people though.
Since clams don’t leave their shells, the eggs and sperm need to. When the breeding season is going on, female clams will release literally millions of eggs into the water, in hopes that there is a nearby male ready to do his share of the work. Assuming there is, the male will release his sperm cells into the water as well, and they go in search of an egg to fertilize.
As soon as fertilization takes place, the cells begin to divide rapidly. This cell division eventually produces larvae. Larvae continue to grow and change, and eventually tiny little clams are formed. These clams then make their way to the bottom of the river, ocean, or lake and nestle into the sand or mud where they grow and mature.
As stated above, there are certain requirements that must be met in order for reproduction to even be considered. The most important factor is water temperature. The water must be rather warm in order for the clams to release the cells into the open water. Because of this, the breeding period can differ depending on latitude and water currents.
Food must also be abundant during breeding time. Ideally, the water will be chock full of planktonic food. If it is, then in no time little clam larvae will be developing and swimming towards the water’s surface in order to be carried away on the waves or wind, thus spreading the population.
Since the spawning cycle relies heavily on water temperature and food abundances, peaks and valleys will occur in cell releasing. These peaks are referred to as “pulses,” and allow the clams to minimize the amount of wasted cells.
These pulses may last for months, depending on region. In areas where the water is warm in summer and spring, the cycle may start in early April and go until late September, stopping completely during the winter time.
Although clams like to bury themselves in much and mud, they are not immune to cold temperatures altogether. In fact, their growth depends on pleasant temperatures. As with the breeding cycle of clam reproduction, clams tend to grow only during spring months, when the water is warm and full of appropriate food sources. As summer sets in, growth slowly winds down. In the winter or colder water spells, however, the clam will simply cease growing and get a bit thicker instead of longer in length.