Subject: Gray Whale migration and Global Warming

Dagmar Fertl (Dagmar_Fertl@mms.gov)
Mon, 4 Jan 1999 08:27:22 -0500

     Subject: Grey Whale migration
     Author:  "Peter L. Frey" <pfrey@ix.netcom.com> at ~smtp
     Date:    12/24/98 2:07 PM
     
     
     Dagmar,
     
     First of all happy holidays. I was wondering if you had any
     information or could point me in the direction of information on this 
     years Grey Whale migration from Alaska to Baja. I read an article that 
     there have been no sightings of Grey whales so far this year off the 
     coast of Oregon and that this is an unheard of occurence for this time 
     of year. I am curious if anyone has a theory on why this may be (El 
     Nino? here in California we blamed everything on El Nino last year). 
     Please let me know if you have any insights on this matter or could 
     point me in the direction of some information on this subject.
     
     Thank You,
     
     Peter L. Frey


______________________________ Reply Separator _________________________________
Peter, Thanks for your patience regarding a reply to your question on gray whale
migration.  I have attached a newsclip below that appeared recently in The 
Seattle Times that provides some speculation on this topic.  I'd like to take 
advantage of your question to inform WhaleNet readers a little about gray whale 
migration, El Nino, and global warming.  Incidentally, it's not just grays that 
seem kind of funky this year with the migration, even the bowheads off Alaska 
were lingering in areas that they usually vacate earlier.

You may know already that gray whales migrate in pulses.  What this means is 
that all gray whales do not start migrating at the exact same time (which is why
you don't see massive numbers of gray whales at any one point in time during 
their migration).  While it is true that the migration is maybe not 'typical' of
what you might be used to seeing, there have been grays sighted on the migration
route(s).  A friend/colleague of mine spent Christmas Day off San Francisco 
watching some grays migrate.

Global warming might be a real consideration.  A colleague who was recently in 
the Antarctic said that a chunk of fast ice, the size of Rhode Island, broke off
while they were.  Breaking up of fast ice like that is definetely a sign of 
global warming.

The El Nino event is when large-scale wind-related conditions favor tranport of 
warm, low-salinity, low-nutrient water towards the coasts of Ecuador and Peru 
(El Nino itself is the warm water current).  El Nino counters (suppresses) the 
usual upwelling of cold, salty, nutrient-rich water, which is basis for high 
productivity (for fisheries and for animals like whales, penguins, etc.).  The 
best- known consequence of this event is the reduction of productivity.  This is
really a southern hemisphere event, but it, of course, has far ranging 
repercussions elsewhere (including off and over the United States).  The El Nino
event inhibits the usual upwelling conditions (important for bringing nutrient 
rich waters to the surface for productivity) and resulted in warmer surface 
temperatures and lower nutrients and chlorophyll in places like off California. 
If you get a reduced phytoplankton situation, it snowballs to mean less 
zooplankton abudnace and lower recruitment success for fishes.  This in turn, of
course, also affects whales.

Persistent El Nino has long been speculated by proponents of the global warming 
theory to be one of the predicted signs.  There are two models which both pretty
much indicate reduced primary productivity -- this is probably the greatest fear
associated with global warming for marine systems.  How this will affect whales 
in the long term is not exactly known.  The International Whaling Commission did
hold a workshop on the effect of climate change on cetaceans in Hawaii a few 
years ago, so as you can see, this is currently an issue of concern for 
cetaceans.

Thanks for your great question! 

Dagmar
*******************************************
KODIAK, Alaska (AP) - Gray whales that summer in the
Bering Sea but should be headed to Mexico by now instead are massing off Kodiak 
Island, leading scientists to speculate that warmer ocean temperatures may be 
responsible. 

"It's very unusual that they're here so late in the year," said Kate Wynne, a 
University of Alaska marine mammal biologist. "It's also unusual that they're so
close to shore on their southbound migration." 

Bird watchers working on the Audubon Society's annual Christmas count spotted 
hundreds of whales Sunday off Narrow Cape, on Kodiak's east coast. 

Wynne wasn't sure why the whale migration is late this year but said warmer than
usual sea temperatures could have played a role.

Meanwhile, a Seattle biologist says she is waiting for the whales to arrive in 
force off the Washington coast. 

"In surveys we've flown to 30 miles offshore we have seen very few gray whales,"
said Sue Moore of the National Marine Fisheries Service's Alaska Marine Science 
Center. "Reports from Oregon say few whales have passed by there, too." 

The Makah Indian tribe at Neah Bay has been waiting for the migration to resume 
a whaling tradition that has been dormant for seven decades. 

Another fisheries service biologist, Dave Rugh, said one sighting of whales off 
Kodiak, unusual though it may be, isn't enough to say conclusively that the peak
of the migration still is in the Gulf of Alaska. 

"We don't have a timeline," Rugh said yesterday. "We don't have someone who was 
watching (the whales) for two months." But he suspects the middle of the 
migration probably was off Kodiak during the weekend. 

Fisheries service biologist Rich MacIntosh, who organized last weekend's bird 
count, said he spotted at least 100 whale spouts
off Narrow Cape in less than one minute. 

"I think there might easily have been a few hundred whales there, but they were 
pretty far off shore so it was hard to tell precisely," he told the Kodiak Daily
Mirror.

Each year gray whales make round-trip migrations from breeding grounds off 
Mexico and California to the Bering Sea. 

Moore said the gray whales are known to stay on the Bering Sea feeding grounds 
     longer during years with less ice, "so perhaps water temperatures are 
     as good a guess as any."