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Gray Whale Migration Update: February 25, 1998 Today's Update Includes:
Gray Whales Give Birth Off California Coast Read the news in the Field Reports below! Then see if you can answer this question:
(To respond to this Challenge Question, please follow the instructions at the end of this report.) News from Channel Islands National Marine Sanctuary Santa Barbara, CA New Gray Whale Observation Posts Meanwhile, as the migration moves up the coast towards Alaska, Susan Payne is racing the whales. She's working to set up additional observation posts along their route. Make a list of the new posts mentioned and see if you can find them on a map of the West Coast. As you look at the long distance from Baja to the Arctic feeding grounds, a question will probably come to mind:
(To respond to this Challenge Question, please follow the instructions at the end of this report.) Field Notes from Kodiak, Alaska February 25, 1998
Since I wrote you last on February 11, I have not had any whale reports from Kodiak come my way. The northbound reports from Santa Barbara are exciting so I decided to make some contacts along the coast. On February 11, Monterey Bay Whale Watch in Monterey, California saw 3-8 northbound gray whales. On Sunday, February 22 their cruise saw 5-15 gray whales and 20 Risso's dolphins at approximately 36 40.32 North Latitude, 122 00.99 West Longitude. They are seeing whales 1-4 miles offshore. Weather on the California coast has been difficult as you may have heard on the news so the Monterey Bay Whale Watch cruises have not been out everyday. On January 15 Nancy Black from the Monterey Bay Whale Watch was lucky enough to witness the birth of a gray whale. Soon they will have the account on their webpage but in the meantime I will relate to you the story from the Monterey Herald: "The mother whale's strange behavior was first noticed by Capt. Richard Ternullo, who pointed out that the whale was lifting the region between its tail and dorsal area and was swimming slowly in circles. About five minutes later a big pool of blood came to the surface. Then the calf popped its head up to get its first breath of air. The calf was flailing its tail flukes and clumsy for about 10 minutes, then was swimming with its mother real slow". According to Nancy the mother/calf pair continued on their way south. You might wonder why the mother gave birth so far from Baja where gray whales usually give birth. According to Dave Rugh, they think that the whales left the Bering Sea later than usual this year because of warmer sea conditions. David Rugh works for the National Marine Mammal Laboratory of the National Marine Fisheries Service and is the principal investigator for the Gray whale project to census the population of gray whales as they pass Granite Canyon near Big Sur in California. He suspects that the migration through California is later this year. But because they are just now finishing the survey and have not had a chance to look at their data they do not know yet if the median date for whales passing their survey site is later this year. David says that the migration has been starting later each year since the mid-1980s. He also reports that their records and those of the American Cetacean Society near Los Angeles are showing higher calf counts than have ever been reported before. The gray whale gives birth about the same time each year within a 5-6 week period, with the peak occurring about January 10 (Rice and Wolman 1971). David suspects that the births are happening before the moms reach a Baja destination because of the later migration. Apparently, David's survey team may have also witnessed a birth in front of their survey site. I should tell you that a note from David on February 13 indicated that the observers at Granite Canyon are still seeing southbound whales (5-10/hr on February 12). He says this means the northbound migration is still a ways off and usually starts at the end of February in that area. I will try to get an idea from David as to what Monterey Bay Whale Watch has been seeing and let you know. In Newport, Oregon our contact is Marine Discovery Tours and because of weather they have not been out in a month. They have a cruise planned today and this weekend so we can hope for some sightings from them. In years past they have seen the peak of the first phase of the migration in mid-March. Some years they see some juveniles all year around outside Newport, Oregon. We are very excited here in Kodiak to have David Rugh confirm his coming for Whale Fest. His talk will be "How many Gray whales are there?" I hope the whales have arrived by the time he does... Signs of Spring Susan Payne References Bering Sea: Sea Surface Temperature Rice, D.W., and Wolman, A.A. (1971). The life history and ecology of the gray whale (Eschrichtius robustus).
Spec. Publ.-Am. Soc. Mammal. 3, 1-142. Reminder: Challenge Question # 1 In light of the migration news provided today, now how would you answer this question?
Clues: Reminder: Please Help Track Gray Whale Migration If you live along the Gray Whale migration route on the West Coast, we hope you'll help provide gray whale migration data this spring. To track the whales' trip to their northern feeding grounds we are collecting the following information: 1) Date of first sighting of northbound gray whales. 2) Date of first sighting of northbound gray whale mother/calf pairs. Obviously, you would need to watch for whales every day to accurately report these "firsts" of the season. Therefore, we encourage you to contact the captain of one of the many whale-watch vessels in your area. These people are lucky enough to be out every day and can provide accurate data for you. How to Respond to Journey North Gray Whale Challenge Questions: Please answer ONLY ONE question in each e-mail message: 1. Address an e-mail message to: jn-challenge-gwhale@learner.org 2. In the Subject Line of your message write: Challenge Question # 1 (or #3 or #4) 3. In the body of the message, give your answer to the questions above. The Next Gray Whale Migration Update Will be Posted on March 11, 1998. Copyright 1998 Journey North. All Rights Reserved. |