Answers From the Whale Expert
My apologies for not answering these questions sooner. We've been extremely busy here at the Santuary with many programs including development of new guidelines for whalewatching vessels in the Northeast (working with the National Marine Fisheries Service) and preparing for our Sustainable Seas Expedition with National Geographic Society--be sure to follow along with this exciting program! Thank you for your interest in whales, and, as you will see from my answers, there's a lot we don't know about whales and many areas for research (perhaps yours?) in the future.
Platteville School, Platteville, WI
Q. Why don't researchers use radio telemetry tracking for right whales. If they are so scarce wouldn't this be a more reliable and effective stratagy to study this creature?
A. Actually, researchers do use radio tags in some studies of right whales. For long distance tracking, the satellite tags provide a long-term solution--particularly for keeping track of entangled whales (and deciding when a rescue attempt can best be mounted). Usually these tags are attached to the trailing lines or entangling fishing gear. But to follow minute by minute, hour by hour movements, the radio tag has proved to be most helpful. Radio tags require that researchers stay rather close to the whale--mainly because the signal cannot travel too far.
The curvature of the earth also plays a role. Boats needs to stay within a few miles and planes can receive signals some ten times farther. But basically, it's the rule of line of sight (the signal travels in a straight line out from the tag). All tags, radio or satellite, must be attached to the whale somehow. A non-invasive method is to use suction cups with a gel coating (like larger versions of the suction cups used during medical EKGs -- electrocardiograms -- in the doctor's office). But as you may know from toys that use suction cups to stick on walls, these devices only work for a short period of time. Eventually, they will drop off.
I accompanied scientist David Wiley from the International Wildlife Coalition on one right whale research cruise where the tag stayed on for some seven hours. Sometimes they stay on for twice that length of time, sometimes they come off in half the time. Some tags have been fastened to whales with hooks that enter the blubber, but even these work their way out. Whales are very active animals, and breaching, diving, and social behavior including rubbing together can dislodge even the best placed tag. Getting a tag on a whale is also a very difficult task. First, the scientists must get close enough, then they have to be lucky and skillful in placing the tag in a place where it will be able to break the water's surface and get its signal back to the receiver.
The batteries and all equipment must work -- and the marine environment (salt water) is extremely hard on electronic equipment. And finally, they have to be able to recover the tags when the test is done. This is no small task -- and an expensiv one too, if you figure in vessel time and equipment costs.
Q. What is the most interesting fact you have uncovered so far in your research of the right whale?
A. Although I don't do any research on right whales (I am the education coordinator of the Stellwagen Bank National Marine Sanctuary), I often work with scientists. And I've learned a lot of really interesting things about whales. One of the interesting theories that came out of the satellite tag track of the entangled right whale Metompkin several years ago, was that the tag's signal ended up in an area of the eastern Atlantic Ocean northwest of the Azores. No one knows for sure if the tag was still with the whale or if it came off the entangling gear or if the gear with tag drifted off on its own. What some researchers have found is that the signal ended up in an area that an eighteenth century navigator marked as a possible right whale habitat.
I've also found out that southern right whales have come under some serious harassment -- not from humans, but from gulls. These birds have found that they can peel great sheets of skin off the backs of resting whales. As dumps and human refuse increase worldwide, the gull population has exploded. These animals have adapted quite well to human society, and to feed their growing numbers they have been finding new sources of food. This whaleskin feast may be disturbing the whales far more than many human actions.
For humpback whales one interesting thing I have found out is that they may be "right-handed" or "left-handed" just like us. Studies in the Stellwagen Bank National Marine Sanctuary on feeding behaviors of humpback whales, showed that (during a period of low sand lance numbers) the whales were scraping the bottom to chase the fish out of the sand. Based on the scuff marks on their lower jaws, the scientists were able to tell if the whales were "righties" or "lefties." The breakdown was about 80 percent right and 20 percent left (human percentages are slightly different at 90-10).
Scott Young Public School, Omenee, Ontario
Q. How can you translate the data for the humpback whale migration patterns?
A. Based on years of observations, researchers know the general timing of migrations -- and plan their research programs around these times. In some areas, businesses relating to whale arrivals have grown (whalewatching in the feeding and calving grounds). But due to the fact that tagging is so difficult (and most tags do not stay on whales -- usually best placed on entangling gear), tracking healthy whales is a difficult task. We know the least about the middle parts of the whales' migrations. One experiment in the Pacific Ocean with a satellite tag indicates that a humpback whale there made a direct northward migration from Hawaii to Alaska. We suspect that humpbacks may hug the Atlantic coast of North America on their southward migration but swing out a bit on their northward route (and move past Bermuda based on sighings their in the early spring). Scientists need a good base of observations and years of data in order to develop theories about whale behavior.
Q. What is the average lifespan of a humpback whale?
A. We know that the oldest known right whale is at least 65 years old, based on sightings in 1934 when the adult whale was first seen and subsequent sightings into the 1990s. Scientists suspect that whales (including humpbacks) may have a lifespan similar to that of humans (but remember that life in the oceans is a harsh existence). Although some have said that whales may reach ripe old ages, the age I most often hear mentioned as a whale lifespan is about 40-50.
Q. How long is the term that a humpback whale carries its calf before it's born? Stephen & Ryan, gr. 5
A. Humpback whales breed in the Caribbean Sea and give birth there too. Scientist believe that humpback whale gestation (the time for the fetus to develop) is about one year. Other whales may have longer or shorter pregnancies, depending on the species.
Q. Why do gray whales have parasites on their backs?
A. All whales seem to host other species -- although we don't know for sure if they can really be called parasites. Whale lice tend to be specific for their whales -- particular species of these small crustaceans live on particular species of whales. The whale lice are actually kinds of cyamid amphipods. Gray whales have them, humpbacks have them, blue whales too. In the right whale the species are Cyamus ovalis and Cyamus gracilis, in particular, and occasionaly C. ceti, C. erraticus, and C. catadontis. Scientists are not really sure of the function of these "hitchhikers." They may be eating old skin in a natural cleaning process, or available to clean wounds when needed. They may be taking food from the water that the whales swim through. Other whales, including humpbacks, have barnacles growing on their bodies. Breaching behavior may be a means of knocking this extra weight off their bodies.
Q. Do gray whales have any other predators than humans?
A. Adult great whales (minke, sei, gray, right, bowhead, humpback, finback, blue, orca, spern) do not have any other predators other than humans (and most nations have agreed to abstain from whale hunting). Today Norway and Japan are the only nations that hunt large numbers of whales (minkes). Some aboriginal populations hunt small numbers of whales for food and cultural purposes. However, whale calves have been preyed upon by orcas -- and some sick animals may be attacked by large sharks (there was a case of a sick humpback attacked by sharks in Hawaii several years ago). It was reported that gray whales migrating northward past the Channel Islands off California last year had to run a gauntlet of orcas that were probably targeting calves that strayed too far from their mothers or weak, sick adults.
Q. Are gray whales sensitive? Kate, Stephanie & Danielle, gr. 5
A. All whales are mammals, and they have sensory organs like us. They hear, they see, they have nervous systems and can feel pain (just read some of the whaling journals). Whales are often seen rubbing against each other, sometimes in what appears to be a tender manner -- particulary between mothers and calves. Humpback whales seem to be curious and will approach boats. Gray whales are quite mellow in their southern calving grounds. Researchers believe that whales have a highly evolved sense of hearing, using a range of sounds. Toothed whales are noted for their echolocation abilities. So, all whales can be said to be sensitive in many ways.
North Albany Elementary, Albany, OR
Q. Why did poachers kill Humpback Whales and let them sink to the bottom of the ocean? We read about this in a book.
A. Poachers would probaby set out to kill whales for their blubber and baleen or teeth, but it was probably an accident that the whales sank to the bottom. Most whales will sink when they are dead (not so the right whale -- that was one of the reasons why it was called the "right" whale). In many cases, gases will build up in the body of the dead and decaying whale, causing it to rise to the surface. Perhaps what you read about involved this natural process which the poachers may have capitalized upon.
Q. Humpback Whales are down in Hawaii and migrate up and down the east coast but they aren't on our (Oregon) coast. Why?
A. Humpback whales in Hawaii migrate northward to the Aleutian Islands and western Alaska. But there are humpbacks that can be found along the Pacific coast of North America. These whales range from Central America to Southern Alaska, migrating past California, Oregon and Washington. There have been research cruises off Oregon and Washington's Strait of Juan de Fuca.
Stellwagen National Marine Sanctuary
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