國(guó)家地理:水母為何如此迷人(4)
Then there are the ctenophores (pronounced TEH-nuh-fores), which are such oddballs they've been placed in a phylum of their own. Also known as comb jellies, for the comblike rows of tiny paddles they use to swim, they tend to be small, delicate, and hard to study. They come in an array of weird body types: Some are flat and ribbonlike; others look more like pockets or little crowns. Most use an adhesive to nab their prey. "They have what's like exploding glue packets embedded in their tentacles," explains Steve Haddock, a senior scientist at the Monterey Bay Aquarium Research Institute.
此外還有櫛水母（發(fā)音為T(mén)EH-nuh-fores），由于它們實(shí)在太古怪了，所以自成一門(mén)。它們也叫做comb jellies，這是來(lái)自它們用來(lái)游泳、一排排像梳子的櫛板，這類動(dòng)物往往體積小巧，非常脆弱，因此難以研究。櫛水母有各式各樣怪異的體形：有些呈扁平緞帶狀，有些看起來(lái)像口袋或小皇冠。大部分櫛水母都會(huì)用一種黏液來(lái)捕捉獵物。“它們的觸手里面埋著一種類似爆炸黏膠包的東西”，蒙特利灣水族館研究所資深科學(xué)家史蒂夫·哈達(dá)克解釋道。
In recent decades jellyfish populations in some parts of the world have boomed. In the 1980s a comb jelly that's known formally as Mnemiopsis leidyi and informally as the sea walnut showed up in the Black Sea. A native of the western Atlantic, it presumably had been transported in a ship's ballast water and then been discharged. In the Black Sea it reproduced so prolifically that by 1989 it had reached densities of up to 11 per cubic foot of water. Fish couldn't compete with the jellies for food -- sea walnuts eat as much as 10 times their body weight a day -- and many fish became food for the jellies. Local fisheries collapsed.
近幾十年來(lái)，世界上有些地方的水母族群激增。20世紀(jì)80年代，一種官方名稱叫梳狀水母、俗稱海胡桃的淡海櫛水母出現(xiàn)在黑海。這種原生在大西洋西部的櫛水母，可能是被船艦的壓艙水運(yùn)到黑海水域后排出。淡海櫛水母在黑海大量繁殖，至1989年的密度已經(jīng)高達(dá)每立方公尺海水有11只個(gè)體。當(dāng)?shù)氐聂~(yú)類無(wú)法與淡海櫛水母爭(zhēng)奪食物（淡海櫛水母每天會(huì)吃掉體重十倍的食物），許多魚(yú)兒也成為櫛水母的食物。結(jié)果就是，當(dāng)?shù)貪O業(yè)崩潰了。
In other parts of the world, swarms of jellyfish have menaced swimmers and clogged fishing nets. In 2006, beaches in Italy and Spain were closed because of a bloom of jellyfish known as mauve stingers. In 2013 a Swedish nuclear plant temporarily shut down because moon jellies were blocking its intake pipes.
在世界上其他地方，成群的水母對(duì)泳客造成威脅，也堵塞了漁網(wǎng)。2006年，意大利與西班牙因?yàn)橐构庥嗡复罅砍霈F(xiàn)而關(guān)閉海灘。2013年，瑞典的一座核電廠因?yàn)楹Ｔ滤付伦∵M(jìn)水管而暫時(shí)關(guān)閉。
Situations like these led to a spate of reports that jellyfish were taking over the seas. One website warned of the "attack of the blob." Another predicted "goomageddon."
這類情況造成媒體上大量出現(xiàn)水母正接管海洋的報(bào)道。一個(gè)網(wǎng)站警告說(shuō)“水母的攻擊”。另一個(gè)則預(yù)測(cè)“水母大災(zāi)難”。
But scientists say the situation is more complicated than such headlines suggest. Jellyfish populations fluctuate naturally, and people tend to notice only the boom part of the cycle.
然而科學(xué)家表示，實(shí)際狀況比這些頭條新聞所言還更復(fù)雜。水母的族群數(shù)量本來(lái)就有自然波動(dòng)，而大眾往往只注意到周期中大量繁衍的時(shí)期。
