VOA慢速英语2018 神秘生物威胁巨型地中海蛤蜊（在线收听）

Mysterious Organism Threatens Huge, Mediterranean Clam

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 by filtering out organic material from it.

数百年来，笔壳蛤提供了食物和一种不同寻常的材料，这种材料名为海丝，可以用来制作一种布料。这种蛤蜊也会通过滤除有机物质来净水。

The European Union named the pen shell clam a protected species many years ago. The clam has been overfished and has suffered from pollution 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.

欧盟在许多年前就将笔壳蛤列入受保护物种名单。这种蛤蜊一直被过度捕捞，而且遭受污染和水域被破坏的痛苦。另外，禁止捕捞笔壳蛤的禁令也执行不力。笔壳蛤因其不同寻常的巨型外壳而被捕捞，同时笔壳蛤还被用来制作食物。

The pen shells can live for many years, but they take years to reach reproductive age. Now, they are disappearing faster than they can be replaced.

笔壳蛤可以存活多年，但是它们需要数年才能达到生育年龄。而现在，笔壳蛤的消失速度已经超过了其换代的速度。

New parasite alarms experts

新型寄生虫令专家感到担心

A new parasite which first appeared in 2016, has alarmed experts. It is unclear exactly how the parasite kills the clams.

一种在2016年首次出现的新型寄生虫令专家感到担心。目前人们还不清楚这种寄生虫究竟是如何杀死笔壳蛤的。

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 it wiped out (the pen shell population of) the Spanish coast.” Then waters of France, Malta, Tunisia and Italy were affected.

玛丽亚·德尔玛·奥特罗来自国际自然保护联盟。她表示，“在不到一年的时间内，这种寄生虫就消灭了西班牙海岸的笔壳蛤。”随后，法国、马耳他、突尼斯和意大利的水域也受到了影响。

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.

目前人们只知道这种寄生虫的学名是haplosporidium pinnae。研究人员表示，该寄生虫可能还导致了希腊、土耳其和塞浦路斯一些水域的笔壳蛤死亡。

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 scientists are not sure of anything yet, except that the parasite is spreading quickly.

潘特利斯·卡萨里奥斯是希腊海洋研究中心（简称HCMR）的研究员。他表示，除了这种寄生虫的传播速度非常快之外，目前科学家什么都不能确定。

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.

伊安尼斯·伊萨利斯来自希腊海洋研究中心的海洋学研究所。他说，试验表明，这种似乎在杀害希腊笔壳蛤的生物，可能与影响西班牙蛤蜊的生物是同一种。

“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.

科学家正在出现笔壳蛤死亡事件的地中海国家进行试验。希腊一些地区的笔壳蛤十分健康，但其他地区的笔壳蛤却已经消失。

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.

他们发现，受到影响的只有笔壳蛤。与笔壳蛤类似的江珧则没有受到伤害。科学家仍然不知道为什么这种寄生虫对笔壳蛤来说如此致命。

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.

该寄生虫可能来自另一个物种，因为某种原因而跳到了笔壳蛤身上。另外，污染、气候变化或水温变化等其他条件也可能引发这一问题。

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.

他还表示，目前并不清楚笔壳蛤或影响笔壳蛤的微生物会发生什么。巨型笔壳蛤可能因携带这种寄生虫而完全消失。

Words in This Story

shellfish –n. an animal, such as a crab or oyster, that has a hard outer shell and that lives in the water

species –n. a group of animals or plants that are similar and can produce young animals or plants

parasite –n. an animal or plant that lives in or on another animal or plant that gets food and protection from it

digestive –adj. related to the process by which food is changed into a simpler form after it is eaten

stage –n. a particular point or period in the development of something

benefit –n. a good or helpful effect