A microscopic organism is causing a huge clam of the Mediterranean Sea to disappear and ocean scientists are worried.
一种微生物正在导致地中海的一种巨型蛤蜊消失,这令海洋科学家感到担心。
The pen shell clam is the largest shellfish in the Mediterranean. The clam can grow to one meter in length. Its shell looks something like a huge feather.
笔壳蛤是地中海最大的水生有壳动物。这种蛤蜊能长到1米长。其外壳看起来像一根巨大的羽毛。
For hundreds of years, the clam has provided food and an unusual material, called sea silk, which can be used to make a kind of cloth. The clam also cleans water byfiltering outorganic material from it.
The European Union named the pen shell clam a protected species many years ago. The clam has been overfished and hassuffered frompollution and destruction of its waters. A ban on hunting the clam also has been poorly enforced. They are harvested for food and for their unusual, large shells.
Scientists say it appears to attack the pen shell's digestive system. The clam becomes unable to close its shell and can be attacked by its enemies.
科学家表示,这种寄生虫似乎攻击了笔壳蛤的消化系统。笔壳蛤无法关闭外壳,继而被其敌人攻击。
Maria del Mar Otero is with the International Union for Conservation of Nature. She said, "In less than a year itwiped out(the pen shell population of) the Spanish coast." Then waters of France, Malta, Tunisia and Italy were affected.
The suspected parasite is known only by its scientific name, haplosporidium pinnae. Researchers say it also may be responsible for killing pen shell clams in some Greek waters and those of Turkey and Cyprus.
Scientists are now racing to understand how the parasite spreads. This information is needed to protect the clam.
现在,科学家正在努力了解这种寄生虫的传播方式。因为保护笔壳蛤需要这类信息。
Pantelis Katharios is a researcher at the Hellenic Center for Marine Research, or HCMR, in Greece. He said scientistsarenotsure ofanything yet, except that the parasite is spreading quickly.
Yiannis Issaris is with HCMR's Institute of Oceanography. He said tests show that the organism, which appears to be killing the clams in Greece, could be the same as the one affecting clams in Spain.
"This is very fresh for the scientific community," he said, "We're still at the stage of recording where it has spread to."
他说,“这对科学界来说非常新鲜。我们仍处于记录其传播地域的阶段。”
Scientists are carrying out tests in Mediterranean countries where the clams are dying. Some areas of Greece have healthy populations of the clams, but in other areas they have disappeared.
They have found that only the pen shell clams are affected. A similar species, pinna rudis, has been unharmed. And they still do not know why the parasite is so deadly to the pen shell clams.
The parasites might have come from another species and for some reason jumped to the pen shell clam. It also is possible that other conditions including pollution, climate change or water temperature changes could be causing the problem.
Katharios said, "Normally parasites in nature do not have any benefit from harming the host, because they depend on the host."
卡萨里奥斯表示,“一般来说,自然界中的寄生虫并不会因为伤害宿主而受益,因为它们要依赖于宿主。”
He added it is not clear what will happen to the pen shell clams or the microorganism affecting them. The big clams could completely disappear taking the parasites with them.