To: Journey North
From: Anne Smrcina
Stellwagen Bank National
Marine Sanctuary
Very little word on humpbacks this week other than that they are still down south. Humpback researchers in past years had gone to Bermuda in the spring to do migration research (but not in the fall). This year, a lack of funding for whale research projects has led to a reduction in field studies, including the Bermuda research.
CHALLENGE QUESTION #36:
"Why would researchers go to Bermuda in the spring but not the fall?"
(Hint: The reasons have to do with the whales and not the scientists' vacation preferences.)
To respond to this Challenge Question, please follow the instructions at the end of this report.
Last week I asked about humpback whale singing and why it happens. I received many good answers from students in British Columbia, Washington, Maine and Minnesota. As you'll read in their comments below, many students offered answers similar to what the experts say. However, as with all marine mammals studies, we often can't say anything is a sure bet.
Whales usually "sing" in their southern waters, although some whales have been recorded up north singing their songs. Only the males sing, and that sound is probably associated with the effort to attract mates. An article entitled "Whales Ho" written by Dr. Peter Craig and sent in by my counterpart at the Fagatele Bay National Marine Sanctuary in American Samoa (can you find that island on a map?) says:
"While an occasional spout of whale-breath can be seen in our local waters [Samoa], you can hear the whales too, if you stick your head in the water. Humpbacks are famous for their unique "songs." Yes, whales sing! During mating season, male humpbacks sing to either attract females or defend their territory from other male whales, much like birds do with their own songs. The whale's song is haunting and complex. It sounds like an eerie series of chirps, squeaks, whistles and grunts. I know that "grunts" don't seem like they could make much of a song, but you just have to take my word for it. It is unlike anything you have ever heard.
"Scuba divers can hear the singing if they hold their breath and pay attention. Snorklers can also hear the songs, but they have to dive at least 10 feet deep to get below the noisy surface layer of the water. (Landlubbers can listen to the humpback's song in the video 'Star Trek 4' or on any of several audiotapes of whale sounds).
"The song lasts about 10-20 minutes, it has a beginning, middle and end, and all males of the same stock sing the same song. Thus, biologists can identify where a whale comes from by listening to its song. For example, Hawaiian humpbacks sing a different song because they belong to a different stock of whales that migrates between Hawaii and Alaska [and Silver Bank whales sing their own brand of songs. However, whales may individualize their songs with extra chirps or cries, etc. ]. The whales' song is one of the world's wondersof nature."
Whale songs have been heard through the hulls of the ships and on the sonars of submarines and perhaps were the origin for Homer's tale of siren songs in his book "The Odyssey." In Nigel Bonner's book "Whales of the World" he reports that songs may have a range of at least 31km (19.2 miles), with the very low moans having a potential range of 185km (115 miles).
Sounds in most mammals are made by passing air from the lungs through the larynx and over the vocal cords, which vibrate at different frequencies (the sounds are modified in mouth and nasal cavities). Although whales do not have vocal cords, each does have a larynx. But expelling air to make sounds would not be acceptable or helpful for this marine mammal. However, it is believed that the movement of contained air over the larynx may be responsible for the sounds. If you check out the right whale report, you will find information about a whale necropsy. One of the researchers, Joy Reigenberg of Mt. Sinai School of Medicine in New York City, studies whale larynx samples to try to discover how the whales make their sounds. Other partners in that research project include the U.S. Navy and Scripps Institute of Oceanography.
And speaking about Hawaii, Dave Mattila (subject of last week's newspaper article) has arrived in Hawaii and started his research upon the invitation of the Hawaiian Islands Humpback Whale National Marine Sanctuary and National Marine Fisheries Service. He has been working at Penguin Bank off the island of Molokai. He has been seeing bunches of humpbacks, and over the course of the past 3-1/2 days has been able to take 27 whale biopsies (these samples are very hard to take, so this number is excellent). In order to get the biopsy samples, researchers use a cross-bow and dart (with line for retrieval). The dart tip penetrates about 1-2cm into the skin and blubber without doing any harm to the animal. The samples are then used for a variety of experiments.
Here's hoping for good whale sightings this week.
Anne Smrcina
From BRITISH COLUMBIA:
Yes Humpback whales sing in northern waters. Because they have to talk to
each other and to find out where the coast and rocks are. I live on the
west coast of Vancouver Island and I saw a Humpback whale on Monday the 4th
of March. Joel Roberts at Cross Roads B.C.
lyoung@pinc.com
From MAINE:
Hello, I'm studying the Humpback Whale. I live in Southwest Harbor,
Maine and I am a student at Pemetic Elementary school in Fran
Howley's 5th grade class. Our answer to Challenge Question #26 is
that the two whales by Rhode Island are like scouts and they sing to
tell other whales if the water is too cold or just right. Thank you.
Sincerely, Michael Harper & Jillian Sanner Fran Howley
grade5fh@pemetic.u98.k12.me.us
From FLORIDA:
Hello from Karima Anderson at Academic Resource center in Tallahassee,
Florida. I think the Humpback whales sing to communicate to each
other. I think Humpback whales only sing down south because they
usually sing at breeding time and they breed down south.
Journey North Kids journeyn@wane-arc.scri.fsu.edu
From LPMiddle@aol.com
We think that the whales sing because it is a mating call or
communication to say where they are. The humpback whales mate in
the north, so that is where they sing.
Alisha, Marcus, Mark and Thomas
From MINNESOTA:
To attract a mate.
jordan zebeck jordan_zebeck@blake.pvt.k12.mn.us
From WASHINGTON:
The Humpbacks migrate south where it is mating season and they have
their calves. They sing in the south because of the mating season
The Evergreen School Janet Charnley (charnley@halcyon.com)
Shoreline, Washington 4th Grade
How to Respond to Challenge Question # 36:
1. Address an e-mail message to: jn-challenge@learner.org
2. In the Subject Line of your message write: Challenge Question #36
3. In the body of the message, give your answer to this question:
"Why would researchers go to Bermuda in the spring but not the fall?"
The Next Humpback Whale Migration Update Will be Posted on March 20, 1996.
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