英语听力：自然百科 驼背鲸
In the busy waters of the Stellwagen Bank, National Marine Sanctuary, whales mustnavigate around submerged fishing gear. And on the surface, collisions to the ships result in injury and death.
Researchers with the National Oceanic and Atmospheric Administration or NOAA, and theCensus of Marine Life need to know more about whale behavior, so they can better protect the animals.
"Some of the management issues that are really important is to be able to know, um, how they are behaving in areas of high traffic, where we end up with lots of ship strikes, and in that how are the whales moving from one patch to another, what are the things that cue them to go into or out ofshipping channels and some things like that.”
Scientists want to know where humpbacks go underwater and how they forage for food. Leading the study is Dr. David Willey.
"They got two tags, both short-term. Five, six-hour tags. The idea is to try and put them on the animals that are feeding in the same group, and get the multiple foraging strategy.”
Here on the open water, the researchers’ boat seems like a toy compared to the massive humpbacks, which can grow to 50 feet in length. The whales must be tagged by hand, the procedure that takes patience, precision, and oh yes, courage.
"Oh, right under us."
Dr. Ari Friedlander, an expert tagger carefully coordinates his moves with Wiley, the driver. Friedlander reaches out with a pole, and successfully slaps a tag on the flank of a moving target.
Equipped with suction cups, the tag will stay on the whale for up to 24 hours.
"Hey, he’s still up. He’s still up.”
These tags will act as the researchers' eyes and ears, (beautiful) recording audio, and tracking the whale’s movements under the vast, dark waters of the Atlantic.
Designed by Mark Johnson of the Woods Hole Oceanographic Institution, the tag also emits radio signals, allowing the team to follow the whale’s course. When the temporary tag releases at a prescribed time, the researchers quickly retrieve the device. Back at Command Central, the team prepares for the next step, visualizing the tag data.
"So this is a track plot which is some software we’ve developed, which, you can see this ribbon here, that represents the whale's track over several hours. And it helps you see those kinds of events. What you’re seeing here is the animal, presumably bottom feeding, so this is the data that came from just yesterday.
Another visualization program developed by the Center for Coastal and Ocean Mapping replays the whale behavior retrieved from the tags. The innovative tags and visualizations solve many mysteries of whale behavior. The data will become part of the Census of Marine Life, a project to assess marine biodiversity, past, present and future.
These scientific discoveries also aid researchers planning safer fishing methods, and have led to a shift in shipping lanes within the Stellwagen Bank National Marine Sanctuary. Ships now avoid areas where large numbers of whales congregate. By revealing the ocean’s secret world, researchers help keep traffic in this congested waterway safer for all.
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