密歇根新闻广播 五大湖出现太多海七鳃鳗

 

Lakes Superior and Erie have too many sea lampreys.

The invasive fish latch² onto big fish like lake trout³ and salmon⁴ and drink their blood and body fluids. A single lamprey can kill up to 40 pounds of fish in its lifetime.

Marc Gaden is the communications director for the Great Lakes Fishery Commission. It's the commission’s job to keep the sea lamprey under control -- a job that costs about $21 million a year.

Gaden's group reported this month that lampreys are at historic lows in Lakes Michigan, Ontario and Huron.

But lamprey numbers have increased in Superior and Erie.

Gaden estimates that there are 80,000 lamprey too many in Lake Superior.

"Why are they so high in Lake Superior? We don't know for sure, but we think that it could be a rebound⁵; lampreys rebounding⁶ from a couple of very harsh winters," says Gaden.

"You might remember a few years ago we had some harsh winters downstate, and it certainly was the case in the northern parts of the Great Lakes region, as well, followed by a few milder winters, and maybe the lamprey took advantage of that and rebounded⁷."

Gaden adds that there could also be more food in the lake, and therefore more fish for lamprey to prey¹ upon.

And there could be new ways lampreys are getting into the lake.

"One area that we're very concerned about, and we're keeping a very close eye on, is the St. Louis River. It's a very large river at the western end of Lake Superior near the border between Minnesota and Wisconsin. It didn't produce lamprey, it's been polluted, and they've spent a lot of time cleaning up that river system. And it could be in the future a lamprey producer. We don't think it is now, but those are the kinds of things we keep our eye on," he says.

Gaden says in Lake Erie, lamprey levels are three times above the target level (there are about 9,000 too many lampreys). He says although the number of lampreys is on an overall downturn, there's been an uptick in recent years.

"The problem with Lake Erie is lamprey, we think, are coming from outside of the lake. So we've treated all the streams in Lake Erie that have lamprey in them - there's not many. We treat them again, and we treat them again, and we go out there, and we assess it, and sure enough: there aren't many lamprey left in those streams. But yet the numbers are very high in Lake Erie," he says.

The St. Clair River, Lake St. Clair, and the Detroit River are all suspected sources of the lampreys in Lake Erie.

But there could be more money heading toward the fight against sea lampreys. Gaden says the U.S. Senate is proposing about $7 million more in lamprey control.

He says after meeting with Republicans and Democrats⁸ from the Great Lakes congressional delegation⁹, he is cautiously optimistic that the money will come through.

"There's a great amount of enthusiasm for the possibility here. I can tell you that our congressional delegation fights very hard for invasive species funds," he says.

1 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

2 latch   

n.门闩，窗闩；弹簧锁

参考例句：

• She laid her hand on the latch of the door.她把手放在门闩上。
• The repairman installed an iron latch on the door.修理工在门上安了铁门闩。

3 trout   

n.鳟鱼；鲑鱼(属)

参考例句：

• Thousands of young salmon and trout have been killed by the pollution.成千上万的鲑鱼和鳟鱼的鱼苗因污染而死亡。
• We hooked a trout and had it for breakfast.我们钓了一条鳟鱼，早饭时吃了。

4 salmon   

n.鲑，大马哈鱼，橙红色的

参考例句：

• We saw a salmon jumping in the waterfall there.我们看见一条大马哈鱼在那边瀑布中跳跃。
• Do you have any fresh salmon in at the moment?现在有新鲜大马哈鱼卖吗？

5 rebound   

v.弹回；n.弹回，跳回

参考例句：

• The vibrations accompanying the rebound are the earth quake.伴随这种回弹的振动就是地震。
• Our evil example will rebound upon ourselves.我们的坏榜样会回到我们自己头上的。

6 rebounding   

蹦跳运动

参考例句：

• The strength of negative temperature concrete is tested with supersonic-rebounding method. 本文将超声回弹综合法用于负温混凝土强度检测。
• The fundamental of basketball includes shooting, passing and catching, rebounding, etc. 篮球运动中最基本的东西包括投篮，传接球，篮板球等。

7 rebounded   

弹回( rebound的过去式和过去分词 )； 反弹； 产生反作用； 未能奏效

参考例句：

• The ball rebounded from the goalpost and Owen headed it in. 球从门柱弹回，欧文头球将球攻进。
• The ball rebounded from his racket into the net. 球从他的球拍上弹回网中。

8 democrats   

n.民主主义者，民主人士( democrat的名词复数 )

参考例句：

• The Democrats held a pep rally on Capitol Hill yesterday. 民主党昨天在国会山召开了竞选誓师大会。
• The democrats organize a filibuster in the senate. 民主党党员组织了阻挠议事。 来自《简明英汉词典》

9 delegation   

n.代表团；派遣

参考例句：

• The statement of our delegation was singularly appropriate to the occasion.我们代表团的声明非常适合时宜。
• We shall inform you of the date of the delegation's arrival.我们将把代表团到达的日期通知你。