Dam water released to help save massive sturgeon
THE latest effort to save North America's largest freshwater fish from extinction begins this week when water is spilled over a dam in the western state of Montana to encourage the ancient fish to spawn for the first time in more than three decades.
The wild Kootenai River white sturgeon, a toothless beast from the days of dinosaurs, has a large head, armor-like scales, can reach 5.8 meters and 450 kilograms. It takes 20 or 30 years for white sturgeon to mature and reproduce.
An isolated population of the bottom-feeding behemoths lives along a stretch of the Kootenai that passes through Montana, Idaho and British Columbia, Canada. The construction of Libby Dam in 1974 stopped the river from flooding Bonners Ferry, Idaho, but also prevented the high water flows that triggered the sturgeon to move upriver and spawn.
Before the dam, there were an estimated 10,000 Kootenai sturgeon. Fewer than 500 mature adults of spawning age remain.
The effort this week will spill up to 280 cubic meters of water per second over the dam in a huge waterfall for up to seven days, in what scientists hope will push the sturgeon to more productive spawning grounds in Idaho. The water will spill from Koocanusa Reservoir into the Kootenai River, where scientists hope the sturgeon will swim to the Bonners Ferry area.
The US Army Corps of Engineers on Tuesday began sending more water through the dam's turbines, in preparation for opening spill gates today. "The idea is to recreate more of the natural, spring conditions," said Michael Milstein of the US Bonneville Power Administration, which markets the power from the dam. "That is believed to be a factor that led sturgeon upriver to spawn."
It's not known if the ploy will work.
The wild Kootenai River white sturgeon, a toothless beast from the days of dinosaurs, has a large head, armor-like scales, can reach 5.8 meters and 450 kilograms. It takes 20 or 30 years for white sturgeon to mature and reproduce.
An isolated population of the bottom-feeding behemoths lives along a stretch of the Kootenai that passes through Montana, Idaho and British Columbia, Canada. The construction of Libby Dam in 1974 stopped the river from flooding Bonners Ferry, Idaho, but also prevented the high water flows that triggered the sturgeon to move upriver and spawn.
Before the dam, there were an estimated 10,000 Kootenai sturgeon. Fewer than 500 mature adults of spawning age remain.
The effort this week will spill up to 280 cubic meters of water per second over the dam in a huge waterfall for up to seven days, in what scientists hope will push the sturgeon to more productive spawning grounds in Idaho. The water will spill from Koocanusa Reservoir into the Kootenai River, where scientists hope the sturgeon will swim to the Bonners Ferry area.
The US Army Corps of Engineers on Tuesday began sending more water through the dam's turbines, in preparation for opening spill gates today. "The idea is to recreate more of the natural, spring conditions," said Michael Milstein of the US Bonneville Power Administration, which markets the power from the dam. "That is believed to be a factor that led sturgeon upriver to spawn."
It's not known if the ploy will work.
- About Us
- |
- Terms of Use
- |
-
RSS
- |
- Privacy Policy
- |
- Contact Us
- |
- Shanghai Call Center: 962288
- |
- Tip-off hotline: 52920043
- 娌狪CP璇侊細娌狪CP澶05050403鍙-1
- |
- 浜掕仈缃戞柊闂讳俊鎭湇鍔¤鍙瘉锛31120180004
- |
- 缃戠粶瑙嗗惉璁稿彲璇侊細0909346
- |
- 骞挎挱鐢佃鑺傜洰鍒朵綔璁稿彲璇侊細娌瓧绗354鍙
- |
- 澧炲肩數淇′笟鍔$粡钀ヨ鍙瘉锛氭勃B2-20120012
Copyright 漏 1999- Shanghai Daily. All rights reserved.Preferably viewed with Internet Explorer 8 or newer browsers.