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To: Journey North
From: Anne Smrcina
Stellwagen Bank National Marine Sanctuary
Greetings from the Stellwagen Bank National Marine Sanctuary.
Hooray! We have our first documented sighting of a mother-calf pair who have made the trip from Florida to Cape Cod Bay. "Slalom" and her calf were spotted on Friday, March 15 at approximate coordinates 42 degrees 5 minutes N and 70 degrees 15 minutes W (this is just off Race Point on Cape Cod). Earlier this year (Feb. 23) they had been sighted off the coast of North Carolina by Keith Rittmaster of the NC Maritime Museum in Beaufort, NC (coordinates 34 degrees 41.3 minutes N and 76 degrees 42.5 minutes W. Marilyn Marx of the Center for Coastal Studies had previously spotted them off the Florida coast at the beginning of the year.
Slalom is an old friend to New England whale researchers. She was born in 1982 to "Wart" (who has also been seen in Cape Cod Bay this past week) and has appeared here almost every year since birth. Slalom's brother is "Shackleton"-- the wandering whale. You can read about Shackleton in the Sanctuary's newsletter (just look for the newsletter posting).
Over 25 whales have been seen in Cape Cod Bay this week, including 17 who have been identified from the catalog. One of the whales, "Delta," was last seen in Cape Cod Bay in 1983. And "Admiral" was the one reported to be "sailing" last week. Marilyn Marx tells us that they have often seen this whale "sailing" up in the Bay of Fundy.
Whale #2220, the one that washed up dead on the Cape Cod beach last week, was probably entangled late last year. The lobster gear was tracked to a lobsterman in the Bay of Fundy who reported losing his pots and lines sometime between Nov. 15 and Dec. 15. Due to the decomposition of the whale, the scientists were unable to determine exactly when it died (it could have been quite a while), and exactly how. But most evidence points to a boat collision.
Since a long cut mark was found directly down the whale's back, the scientists believe this happened while the animal was alive (dead whales usually float on their backs or sides and collisions would leave marks on places other than the back) . But the fishing gear may have been a significant factor in the whale's demise.
Word from Lisa Conger, who works with Chris Slay on the Right Whale Research team in Florida, is that there are very few whales left down south. The one pair they saw was about 6 miles ESE of the Mayport buoy (near the ship channel). Lisa reports that: "When the aerial survey team sighted the pair, they had a large tug and barge bearing down on them and two large inbound ships just offshore of their position. The tug was contacted directly from the plane on the VHF radio. The captain was given a quick description of the whales and their immediate position relative to the tug. The captain said they would keep a lookout. The plane circled over the whales until the tug captain got a visual on them and passed one-quarter mile to the south of them."
Lisa also notes that the mother is known to be right whale #1701, "Aphrodite." She says, "Two winters ago, she was down here in the calving grounds as a juvenile. Aerial photos revealed that the two fused "islands" on the middle of her head were in the perfect shape of a heart. This along with the fact that she has been seen numerous times as the focal female in courtship groups during the last two summers, is how she was affectionately dubbed "Aphrodite, goddess of love." Aphrodite is nine years old and this is her first calf."
Lisa mentioned "islands" for which Aphrodite got her name. You may know that humpbacks are identified by the patterns on their tails. Here's today's
CHALLENGE QUESTION # 44
"How do right whales usually get identified, and what are these "islands" that Lisa is talking about?"
(To respond to this question, please follow the instructions at the end of this report.)
In answer to last week's question about right whales regulating heat, I received several good answers from students which I have printed below. Right now, though, here's the scoop on that challenge question -- Right whales have developed several mechanisms for regulating heat loss. They have a very thick blubber layer (up to one and a half feet in depth) which keeps the heat in and prevents it from escaping to the outside. This is thicker than most other whales (and was a major reason the right whale was the "right whale" to hunt in whaling days).
In addition, the right whale's body is relatively compact with few appendages thereby reducing the surface to volume ratio. With less surface, more heat can be kept inside. In addition, whales also have decreased breathing rates, which adds to their ability to maintain body heat without expelling it (via warmed air) to the environment.
When they they have to get rid of excess heat (perhaps when they're down in southern waters), they have some sections of the body where blood vessels are closer to the surface (flippers and tail) and blood circulation can be increased for release of heat.
Whales have evolved an intricate countercurrent circulation system that is a precision "instrument" for regulating heat in the body. Veins and arteries are intertwined in the flippers and flukes. The warm arterial blood, fresh from the central core of the whale, passes some of its heat to the colder venous blood which is returning from the outer areas of the appendages. Therefore heat stays in the body.
Also, when a whale dives (usually into colder water), blood is shunted away from the surface. In contrast, when the whale needs to release heat to the environment, its circulatory system increases blood flow in veins near the surface of the flippers and flukes and decreases the amount of blood flowing back to the body core.
One other feature is the evolution of a "rete" in the upper jaw. This is a body of convoluted blood vessels, Y-shaped, running the length of the internal upper jaw and ending in two large lobes in the gap between the baleen plates. Scientists at the New England Aquarium theorize that the whale flushes this area with cold water when the mouth is open while it relaxes internal muscles to increase the flow of warm blood. As cold water flows over the uninsulated surface, heat is lost. Having a rete located in the head is important because of the sensitivity of the brain to excessive heat.
That's all for now. Until next week, this is Anne Smrcina signing off.
Students Answers to Challenge Question # 37:
From PENNSYLVANIA:
A whales blubber and fat hold the heat in their body. They control the heat fy following their diet and eating
habits. The temperature of their body is likely to be from 98 to 99 degrees F. Blubber is an energy reserve for
body heat. Its circulatory system adjusts to conserve body heat and maintain its body temperature.
Brandon Schantz - Richland Elementary School
Audrey Nolte, Librarian
Richland Elementary School
(anolte@bciu.k12.pa.us)
From Glen Head Fifth Grade:
"The whales maintain there body temperature with their blubber, which is fat."
Glen Head School (nsghs@li.net)
From NEW YORK:
"This is Rachel and Tina from Mrs. Berger's class in Roslyn, NY. We think that the rete, in the whale's upper
mouth, is a special kind of organ that helps the whale's body temperature adjust according to the water temperature.
THe whale is also protected by the layers of fat (blubber) that it has accumulated and it acts like an insulator
against cold and heat."
K12robzj@hofstra.edu or jberger@dorsai.org
Joan Berger
From Theresa Harmon's class:
"Elementary thinks the blubber of the whale provides all the necessary protection a mammal needs to maintain
body temperature in the ocean environment. Our conclusion came from the "cool" experiment that we found
on the 3-6-96 Humpback Whale Migration Update. Look it up and try it with your class. It is a lot of fun!"Theresa
Harmon (oge@scsn.net)
From MINNESOTA:
"The Whales blubber insalates their body which helps them to keep warm."Answered by Eric Fleming and
Matthew
Dietrich-Blocker Orono Schumann Elementary
Mike Wilder (0278sel@informns.k12.mn.us)
How to Respond to Challenge Question #44
1. Send an e-mail message to: jn-challenge@learner.org
2. In the Subject Line write: Challenge Question #44
3. In the Body of your message, give the answer to this question:
"How do right whales usually get identified, and what are these "islands" that Lisa is talking about?"
Please include your school name and state or province so other students will know how to reach you.
The Next Right Whale Migration Update Will be Posted on March 27, 1996
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