Answers from the Gray Whale Expert 2008

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Answers from the Gray Whale Expert
Special thanks to expert Kim Shelden for providing her time and expertise in responding to your questions below.


From: Ontario
Scott Young P.S.


Q: Why do the gray whales swim all the way down to Mexico to have their babies? Why don’t they stay were they are because they have enough fat to keep them warm.

A: The moms do have plenty of fat to keep them warm, but the babies don't! When gray whales are born they have practically no fat on their bodies. In fact their skin hangs in folds along their bodies and they look like little tadpoles. So it is much better for these babies to be born in warmer waters away from the cold of the Arctic where mom can nurse them until they get nice and fat for the return trip to Alaska. Baby gray whales gain weight very quickly and grow about 9 feet by the time they are weaned .

Q: How much fat does the gray whale really have?

A. The amount of fat varies greatly, depending on the time of year and age of the whale. When the whales are feeding off Alaska, their body fat increases. When they migrate, they burn fat and lose weight. Body fat is different from blubber, and gray whales are losing mostly body fat when lose weight. Some blubber thickness is also lost during migration, but it is not very much. Blubber thickness can range from 9 cm to 20 cm depending on the age of the whale.

Q: Why do gray whales have so much fat when they swim around a lot? Wouldn’t they burn off a lot of that fat?

A: Gray whales are constantly eating while they summer up north off Alaska. During this time they gain weight by eating the large zooplankton found in the cold waters off Alaska. During the summer feeding season they are not traveling the long distances they do when they migrate. During the migration south to Mexico then back north to Alaska, gray whales feed opportunistically (only when and where the find food) but they are expending much more energy swimming during the migration. Some whales become quite skinny before they return to Alaska.

From: Michigan
West Ottawa Public School

Q: Do whales migrate to the exact same area each year and how can we be certain?

A: One way researchers can tell if whales migrate to the same areas is by photographing the whales and looking for unique marks on their bodies. This is called photo-identification. This technique has been used to track humpback whales, killer whales, bowhead whales, and many other species. In fact, scientists using photographs found that about 70% of the gray whales found off Sakhalin Island, Russia, return to the same feeding areas year after year. Scientists call this "seasonal site fidelity."

Q: Can we define the "gps" system they use to navigate?

A:
This is a great question, and one that scientists continue to investigate. Some researchers speculate that gray whales use landmarks, keeping the coast in view most of their migration — but no one really knows how any of these whales navigate the oceans.

Q: What effect will global warming have on these animals?

A: Many scientists are investigating this important question. Gray whales appear to be ranging farther north now that sea ice does not block their way to the Beaufort and Chukchi Seas. Going farther north has meant they must travel farther to get to Mexico from Alaska. As a result, the peak numbers of whales that pass counting stations on the California coast are now as much as a week later than they used to be, and we have been seeing more calves born before they reach the lagoons in Mexico. Recent sightings also show that gray whales are feeding in new areas along their migration path. It is hard to know if gray whales can continue to adapt to the changes occurring in their environment.


From: Massachusetts
West Tisbury School

Q: Our multiage class (6-8 year olds) have been studying the whaling history of Martha's Vineyard and whales. They want to know: Did the whalers ever hunt gray whales for oil? Were gray whales hunted for anything?


A: Yes! Gray whales were hunted so extensively that they were put on the Endangered Species list. The following description can be found in a book by Dale Rice and Allen Wolman (1971) called The Life History and Ecology of the Gray Whale, (Eschrichtius robustus).

Gray whales found in the winter off California were hunted from 1846 to 1900. It was in 1846 when whalers discovered the wintering lagoons along the west coast of Baja California. From 1860-1861, about 60 American whaling vessels were whaling in the lagoons. In 1854, the first shore whaling station was established and by 1874 there were 11 stations strung along the coast of California and Baja California. About 10,800 gray whales were killed during that time. Some were also killed in Alaska waters. By 1886 only 5 whaling stations remained. Whalers continued to catch and kill gray whales in small numbers until 1946 when commercial whaling of gray whales was forbidden by the International Convention for the Regulation of Whaling. Unlike other large whale populations, these gray whales were able to recover from commercial whaling, now numbering about 20,000 whales. Aboriginal hunting of these whales is still allowed along the Russian coast and the Native American Makah tribe of Washington state has requested permits to hunt these whales as well.

Q: Do they often follow boats and spyhop on people? How do they play? How do they react to people?

A:
Some gray whales are referred to as "friendly" because they seem to be curious, approaching boats and allowing themselves to be touched. Others, such as moms with babies, can be very protective. They may move away from boats, or if they feel their baby is threatened, lash out at the intruder with their powerful flukes. It is important to remember that whales are a protected species and many countries have laws about keeping your distance. It is okay if the whale approaches you, but not for you to chase or disturb the whale.

Q: How high is their spout, how long does it last?

A:
A gray whale can spout about 3 to 4 m (10-13 ft) into the air. The spout will be taller and higher if weather conditions are calm. A spout can be visible for about 20 seconds (by which time the whale has probably spouted again).


From Minneapolis, Minnesota

Q: What are some kinds of current gray whale research that you know of?

A:
There are many different projects studying gray whales at this time. Researchers are in the Mexico lagoons counting whales and looking to see if animals appear healthy. Some researchers are in shore stations from Alaska to California counting the whales as they migrate north and south to find out the total abundance of the population and the number of calves being born. Others are studying areas where gray whales feed in waters off Washington state, Canada, and Alaska. There are also scientists studying gray whales that may be effected by oil and gas drilling in Alaska and Russia.


How to Use FAQ's About Journey North Species
Since 1995, experts have contributed answers to students' questions about each Journey North species. These questions and answers are archived in our FAQ's (Frequently Asked Questions) section. You can use today's Answers from the Expert above, along with those from previous years, in the activities suggested in the lesson, "FAQ's About Journey North Species."