BARBARA KLEIN: I'm Barbara Klein.

STEVE EMBER: And I'm Steve Ember with EXPLORATIONS in VOA Special English. Our subject today is whales. We discuss a report on the effect of noise from ships on the behavior of whales. And, we visit a whaling museum on the island of Nantucket in Massachusetts.

(MUSIC)

BARBARA KLEIN: Passenger ships, trade ships, and fishing boats are a normal part of life on the open sea. However, all their activity creates a great deal of noise underwater. Scientists from the United States and Canada recently reported their observations that the ocean is getting noisier.

(SOUND)

STEVE EMBER: That is sound recorded with equipment placed underwater near the busy shipping lanes off Vancouver Island in Canada. Scientists at the University of Victoria have studied the recordings. They say engine noise is continuous during the day, and a little less intense at night.

Scientists say it is likely that whales must call out more loudly to be heard over this noise. The noise could make it more difficult for orca whales to find food. The orcas find fish by producing clicking sounds and other noises. Loud engine noise could be interfering with their efforts.

BARBARA KLEIN: Michael Jasny is a policy expert for the Natural Resources Defense Council. He says the rise of underwater noise is restricting the ability of whales to communicate.

MICHAEL JASNY: "Shipping noise falls across the same frequencies that these animals use for all their vital behaviors - for feeding, for finding mates, for avoiding predators and for navigating."

BARBARA KLEIN: Mr. Jasny says sound travels very effectively underwater. And it is not just whales he is worried about.

MICHAEL JASNY: "The entire web of life in the oceans depends on sound. And as more and more research has been done, it's been very clear that what we have on our hands is really a major problem. It's a serious problem. It's global problem. Fortunately, in shipping we have a problem that has a solution."

STEVE EMBER: One answer is to design quieter ships. America's National Oceanic and Atmospheric Administration, or NOAA, has four new ships that are made to be quieter. Michael Bahtiarian works for Noise Control Engineering, the company which helped design the boats.

MICHAEL BAHTIARIAN: "These NOAA ships show that you can get fairly quiet - I think quiet enough -- because they are able at 11 knots to go up and count a fish and not startle the fish so they can actually count it."

STEVE EMBER: Mr. Bahtiarian says the main source of noise pollution is the propeller. Better shaped propellers and ship designs can help to reduce noise. NOAA's ships also have costly engines, which produce less noise. Mr. Bahtiarian says the technology to make quieter ships does exist and has been used in the military for some time.

BARBARA KLEIN: The shipping industry in the United States wants to be part of the answer to the noise problem. Kathy Metcalf works for the Chamber of Shipping of America. She says it will be much less costly for the industry if it chooses to build quieter ships instead of being forced to do so.

KATHY METCALF: "What our approach is is that if we're progressive now and begin the changeover in the design of ships before we are forced to do it, it will be much less costly to the industry."

BARBARA KLEIN: Ms. Metcalf says the shipping industry expects better ship designs to result in fuel savings. She says this could make the changeover in design more popular.

Ms. Metcalf says the best place to work on new shipping rules is the United Nations' International Maritime Organization. She estimates the reform process could take five years.

(MUSIC)

STEVE EMBER: The island of Nantucket off the coast of Massachusetts is a popular get away place for summer travelers. Today, the main economy of the island has links to the travel industry. But years ago, Nantucket was the world's leading port for whaling ships. Visitors to the town of Nantucket can learn more about this period of history by visiting the Whaling Museum.

BARBARA KLEIN: Deep-sea whaling in Nantucket began in the early 1700s. The people there specialized in hunting the sperm whale, which was known for its valuable oil. Nantucket was at the center of the whale trade for a century, starting in the 1750s.

Nearly everyone on the island was involved in some part of the whaling industry. Whaling ships would make long trips to hunt for whales. The ships had all the equipment necessary for catching and killing whales and also cooking and storing their oil.

STEVE EMBER: The main room of the Whaling Museum gives visitors an idea of how difficult and dangerous it was to hunt a whale. In the center of the room is a whaleboat which could hold six men. The 14 meter-long skeletal remains of a sperm whale hang directly above it. The whaleboat looks very small next to this big sea creature. When sailors sighted a whale at sea, several whaleboats were lowered into the water from the much larger whaling ship.

A Whaling Museum speaker gives us an exciting description of the hunt.

SPEAKER: "Six men in the boat, mates in the stern, harponeers in the bow. Four men are at the oars. You are at one of these oars and you start rowing after the whale with 12 to 14 foot long oars and off you go after this whale."

BARBARA KLEIN: The men would quickly push and pull themselves toward the whale. But they also had to work quietly so that the whale would not hear them come closer.

SPEAKER: "This is very hard work. And if you notice, you're rowing with your back to the whale. You can't see the whale. The mate can see the whale. He is urging you on in a whisper. But you can't see the whale, and that's a good thing. Because if you saw this whale, you would drop dead. He is so scary."

STEVE EMBER: One sailor would throw a sharp harpoon into the whale. The harpoon was on a long rope, which was tied to the boat. The angry and frightened whale would then pull the boat for many kilometers at high speeds, seeking to escape. This was a very dangerous moment for the sailors.

Sometimes the lead sailor would decide to cut the line if the boat risked being pulled underwater. Other times the whale would escape. But often the animal became tired, permitting a sailor to launch another weapon deep into the creature. After the whale was dead, the sailors would then slowly and with great effort take it all the way back to the ship.

BARBARA KLEIN: After the kill, a sailor's work was far from over. The crew worked day and night to remove fat from the whale and heat it in a fire. Boiling the fat and oil was the only way it would survive the long trip. This was hot, dirty and smelly work. One unlucky man on the ship would have to stand inside the whale's head to remove the oil inside it.

MUSEUM SPEAKER: "But these men are not complaining. They know as long as they are boiling oil, they are making money."

STEVE EMBER: Only after the whaling ship was filled with oil would the captain let it return home to Nantucket. This could require three to four years of capturing and killing whales.

The sperm whale skeleton in the museum was not actually part of a whale hunt. It died on a beach of Nantucket in 1998, several days after washing up on land. Experts who examined the remains decided the whale died of natural causes. Some members of the local community had strong feelings about the death and worked to make sure the skeleton stayed on the island.

BARBARA KLEIN: Today the United States and many other countries have rules to protect sperm whales. But in the 1700s and 1800s, the whales were extremely valuable for their clear spermaceti oil, which could be used to make candles and oil for lights. They were also prized for ambergris – a material found in the sperm whale's digestive system. Years ago, ambergris was used to make costly beauty products.

STEVE EMBER: The Whaling Museum's many objects tell a story about life on whaling ships. There are harpoons for attacking whales and tools for cutting their fat. There are records from ships and paintings of famous captains.

Scrimshaw is the art of cutting pieces of whalebone or teeth to make beautiful objects. Sailors would make scrimshaw when they were not busy with their work. The Whaling Museum has a fine collection of detailed scrimshaw. Museum officials say most sailors could not read or write. So they would cut images onto the bone to tell about their trips at sea. They could give these artworks to their loved ones after they returned home.

BARBARA KLEIN: By the 1850s, the whaling economy had come to a close on Nantucket for several reasons. One major reason was the discovery of petroleum, which provided a much less costly form of oil.

The Whaling Museum teaches visitors about an interesting period in history when a small island was a big player in the world economy.

(MUSIC)

STEVE EMBER: This program was written and produced by Dana Demange, with reporting by Tom Banse. I'm Steve Ember.

BARBARA KLEIN: And I'm Barbara Klein. Our programs are online with transcripts and MP3 files at voaspecialenglish.com. And you can find us on Facebook and YouTube at VOA Learning English. Join us again next week for EXPLORATIONS in VOA Special English.

orca: a large toothed whale with distinctive black-and-white markings and a prominent dorsal fin. It lives in groups that cooperatively hunt fish, seals, and penguins 殺人鯨

spermaceti: a white waxy substance produced by the sperm whale, formerly used in candles and ointments 鯨蠟油

ambergris: a waxlike substance that originates as a secretion in the intestines of the sperm whale, found floating in tropical seas and used in perfume manufacture 鯨糞；龍涎香

scrimshaw: 做解悶消遣的手工

Related stories:

殺人鯨的狡猾捕食策略

遭環(huán)保人士圍堵 日本暫停南極捕鯨

鯨魚被曬傷或為臭氧層空洞所致

Whale poo helps planet

（來源：VOA 編輯：崔旭燕）