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Gray Whale Migration Update: May 2, 2001
Today's Report Includes:
- News from the Northern End of the Migration Trail
- Inupiat Eskimos Celebrate Arrival of Bowhead Whales
- Teacher Tip: Ice on the Feeding Grounds
- How Far Can They Go?
- Beast Feast: Challenge Questions #14 and #15
- Going Coastal: British Columbia and Washington Reports
- Lowest Calf Counts? The Experts Speak
- Cow/Calf Pairs: Challenge Question #16
- Whale Wounds
- Channel Islands Marine Sanctuary Observations
- Big Baby! Discussion of Challenge Question #12
- Year-End Evaluation: Please Share Your Thoughts!
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Gray Whale Migration Route |
The whales are spreading out as they reach the icy waters of their summer feeding grounds. Eric Stirrup saw two traveling Grays May 1 from Ft Abercrombie St Park, Kodiak. On April 29, Susan Payne reported 24 grays at Narrow Cape and at least 25 whales off in the distance past Ugak Island. Biologist James Browning of the Alaska Department of Fish and Game has seen many grays on recent flights over the Togiak district while surveying for herring, and saw 24 grays on April 26. Near Seward, Leslie Hines (Captain and Education Coordinator at Kenai Fjords Tours and Marine Science Explorer Program) saw what was very likely a cow/calf pair on April 29! (It wasn't confirmed, but we'll let you know more in our next report.)
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And don't miss the whale bones on exhibit at the school! These photos give you an idea of their massive size,
and you can see more whale bones right in front of this video cam at Nelson Lagoon School:
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Inupiat Eskimos Celebrate Arrival of Bowhead Whales
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Teacher Tip: Ice on the Feeding Grounds
The whales haven't eaten much for months, mostly fasting until their arctic feeding grounds are once again ice-free. Teacher Sheila Gaquin of Point Hope, Alaska tipped us off to a good web site for students. "We are still waiting for some sign of ice-out, but while everyone waits for news of open water, I thought they might enjoy visiting a Web site we discovered:
How Far Can They Go?
When do you think gray whales will be reported as far north as Point Hope, Alaska? Check out the daily ice maps showing open waters and see where the ice stops each day until our next report:
Beast Feast
Feeding is the main activity of hungry whales returning north. During its five- or six-month feast on the Arctic feeding grounds, an adult gray whale will likely swallow at least 67 tons of food. Whales have a lot of weight to gain back after months of living off fat reserves in the calving and mating lagoons and along the migration trail! Susan Payne fills us in with some scientific information on the feasting of gray whales:
After reading, come back and with answers to these questions:
Challenge Question #14:
"What evidence suggest that a gray whale turns onto its side while feeding?"
Challenge Question #15:
"What are feeding tracks?"
(To respond to these questions, please
follow the instructions below.)
Going Coastal: British Columbia and Washington Reports
In Tofino, BC, whale Researcher Rod Palm writes from Strawberry Isle Research Society: "The migration has slowed a bit here off Clayoquot with perhaps a half dozen whales going by in any given hour. The animals do seem to pass in waves so we may just be in a trough at this time. I think most of the males and females without calves have already passed, so we should start to see a surge of moms and calves soon.
"We have one whale who has taken up residence in Grice Bay, 11 miles from the open ocean. This is a small yearling animal, the bay is too shallow for mature sized whales. This bay is one of our monitoring sites where we take monthly core samples from the sediment. The bay has not yet recovered from the particularly heavy predation it suffered two years ago. Biomass levels are still at about half capacity so we're not sure how long this new whale will hang around.
"We have also had a lot of Killer Whale activity this spring with the two species travelling within a half mile of each other but, to date, there have been no interactions.
"Of interest is the fact that we have had no reports of any dead Gray Whales. We generally expect to have a few animals who simply can't make the long migration and strand themselves on our shores.
Off the coast of Washington, Geoff Grillo reports whale watching that's "the best we've seen in years! Lots of sightings and lots of whales later than normal."
Does LATE sum up the 2001 migration? Read on for the official word from the two ongoing gray whale studies happening in California: The ACS counts at Pt Vicente and Wayne Perryman's counts at Piedras Blanca.
Lowest Calf Counts? The Experts Speak
Dr. Wayne Perryman of NOAA's Southwest Fisheries Science Center said, "Things picked up a bit last week. We saw 15 cow/calf pairs, which brought our total for the year to 30. This is still the lowest by this date that we have recorded. Lowest previously was 39 calves (in 1999) and highest by this date was 363 (1998). In a normal year, whatever that is, we would expect to see about 200 calves by the 29th of April. So the migration still looks later than usual, and my guess is that the overall calf count will be low again. Good news is that strandings are down and we haven't seen any of the very skinny whales that we saw last year."
Alisa Schulman-Janiger, Director of the official ACS Gray Whale census on Palos Verde Peninsula (33.44N,-118.24W), comments on the 2001 spring migration for Journey North. Read her letter below to answer these questions:
1. When was the peak week of northbound grays? This was the latest peak in how many years?
2. In how many ways were this spring's counts different from past years?
3. When is the cow/calf migration expected to peak?
4. What date does the ACS census officially end?
"As of 30 April, members of the ACS/LA Gray Whale Census Project at the Point Vincente lighthouse site (courtesy of the U.S. Coast Guard) have counted 438 southbound and 696 northbound gray whales. This is the lowest northbound count ever (and the fourth lowest southbound count). This must be viewed with the knowledge that our past northbound counts to date have varied widely, ranging from 781-3392. Using raw counts only (not adjusting for weather conditions), the peak week of northbound grays was from 24 March-30 March, when we counted 152 grays (averaging nearly 22 grays/day).
"Our two largest northbound counts were on 13 March (31) and 29 March (30). This is a reflection of the fact that we saw whale traffic pass our station in pulses over an extended time period, rather than the more typical, gradual build-up to a defined peak and then tapering off (this was also true of our southbound migration). Past peak weeks have varied from 26 Feb-4 Mar to 19 Mar-25 Mar, with the peak day averaging around 13 March. Therefore, this is the latest peak period we have seen over the 18 consecutive years of our project. This is quite interesting in that both the southbound migration and the turnaround period (southbound shifting to northbound) were quite late this season. We were not sure if a late northbound migration would follow a late southbound migration; these are probably (but not necessarily) related.
"The northbound cow/calf pairs typically migrate past our observation station about 5-6 weeks behind the rest of the northbound whales, which allows the calves to stay in the Mexican lagoon area longer, growing larger and stronger and therefore increasing their survival chances for the approximately 6000-mile journey ahead. Our first northbound calf was spotted on 29 March; the next ones were not seen until 10 April. We have counted 18 northbound cow/calf pairs, with 12 of those spotted between 24 April and 29 April. The peak day so far was 24 April, when we saw 4 cow/calf pairs. Our recent visibility has been hampered by fog, so we could have missed several nearshore pairs. Past northbound calf counts to date have varied from 8-159. Given the timing established by our past observations, we would expect the cow/calf migration to also run late, and to probably peak within the next two weeks (later than our average peak of 22 April). Our station typically closes on 15 May; if the cow/calf migration runs late, we will probably continue counts with a reduced staff.
"Our gray whales have spiced up their passage with many breaches and nearshore approaches. In addition, other sightings over the month of April have been quite remarkable. They include humpbacks on 7-8 days, two days each of killer whales, minke whales, and elephant seals, a very close blue whale and sea otter, a fin whale (with a recent sighting by a boat of a cow/calf pair), in addition to huge numbers of dolphins. We look forward to seeing what the next few weeks will bring!"
Cow/Calf Pairs
Below you'll find the official ACS sighting summary since our last update. What was the peak day for calf sightings? What's your answer to:
Challenge Question #16:
"Of the 696 Northbound gray whales counted by the ACS Census so far, the percentage of cow/calf pairs is ______."
(To respond to this question, please follow the instructions below.)
| Date |
Southbound |
Northbound |
Total Whales |
Calves South |
Calves North |
| 18-Apr |
0 |
3 |
3 |
0 |
0 |
| 19-Apr |
0 |
3 |
3 |
0 |
0 |
| 20-Apr |
0 |
0 |
0 |
0 |
0 |
| 21-Apr |
0 |
2 |
2 |
0 |
1 |
| 22-Apr |
0 |
2 |
2 |
0 |
1 |
| 23-Apr |
0 |
1 |
1 |
0 |
0 |
| 24-Apr |
0 |
8 |
8 |
0 |
4 |
| 25-Apr |
0 |
0 |
0 |
0 |
0 |
| 26-Apr |
0 |
2 |
2 |
0 |
1 |
| 27-Apr |
0 |
11 |
11 |
0 |
3 |
| 28-Apr |
0 |
6 |
6 |
0 |
1 |
| 29-Apr |
0 |
6 |
6 |
0 |
3 |
| 30-Apr |
0 |
3 |
3 |
0 |
0 |
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Season to Date* |
438 |
696 |
1134 |
11 |
18 |
Thanks to ACS volunteers Mike & Winston for the data. Mike also said: "Many of the cow/calf pairs were very active, breaching, rolling and being very playful with their mothers. One mother and calf pair breached 19 times."
Whale Wounds
While observing the migrating Gray whales, we occasionally come across injured whales. Because gray whales migrate close to shore, they are more likely than other whales to get certain types of injuries. Mike & Winston have taken some photographs to help you learn about such things.
Some gray whales very major wounds like this one.
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What do you think may have caused this wound? For the answer and more information about injuries to whales, see:
Channel Islands Marine Sanctuary Observations
Volunteers have provided another great log of sightings for us again. We've put them on their own page. Pull out a map to locate the Sanctuary (near Santa Barbara) and then enjoy picturing what the volunteers saw:
Big Baby! Discussion of Challenge Question #12
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Kudos to Rayne and Kelly from team 7B at Iselin Middle School for sending this thorough answer! They said: "The whale grows about 28 to 30 feet in length in its first year of life. The average is about 29 feet. It grows up to 45 feet in its whole life span. The average length for a whale is about 42 feet. So the fraction of the whale's first year of life is 29/42." That's approximately 5/7.
Year-End Evaluation: Please Share Your Thoughts!
Please take a few minutes to share your suggestions and comments in our Year-End Evaluation Form below. The information you provide at the end of each year is the single most important tool used to guide our planning.
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Journey North |
How to Respond to Today's Challenge Questions:
IMPORTANT: 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 #14 (or #15 or #16).
3. In the body of EACH message, give your answer to ONE of the questions above.
The Next Gray Whale Migration Update Will Be Posted on May 16, 2001.
Copyright 2001 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form
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