WWF organises workshop on climate change in the insular Caribbean
MIAMI, USA: The World Wildlife Fund (WWF) has organised a workshop in Miami on Dec 10-12, to investigate the potential effects of climate change on hawksbill sea turtles (Eretmochelys imbricata).
With the support of the MacArthur Foundation, a group of the world’s best biologists on marine turtles and climate change will gather to study the threats and effects of climate change on this indicator species.
The recommendations of the workshop will be incorporated into an 18 month data gathering and research period, ending with a reconvening of the specialist network to revisit the recommendations and make best use of the information gathered.
Hawksbills are an “indicator species” with which to measure biological effects of climate change since they live in habitats ranging from beaches to the open ocean throughout their lives. As adults, Hawksbills mainly feed on sponges, found on coral reefs, and therefore the fate of coral reefs may be very important to them.
The health of beaches as well as mangrove, sea grass beds, coral reefs and deep ocean ecosystems can be gauged by the presence of sea turtles that use these areas for nesting, foraging, rookeries and migrations.
Increased understanding of how climate change may affect the beaches, the reef and the open ocean will not only benefit endangered sea turtle populations, but also the millions of people who live along the coastlines of the world.
By designing strategies to avoid the negative impacts of climate change, many other species in these environments will also benefit.
Global climate change is pushing many species towards probable extinctions and causing them to shift poleward at rates faster than in geological pasts.
Entire regions are suffering from the effects of climate change and will continue to suffer for the indefinite future.
Eventually all ecosystems will be affected by climate change, as well as the host of other anthropogenic threats that already challenge them (e.g., habitat degradation and pollution).
Some of the most heavily impacted and relied upon ecosystems are rich in biodiversity and sustain essential services.
The Insular Caribbean has a unique biodiversity that supports complex coastal and marine systems (e.g. the Meso American barrier reef – the second largest in the world), making it a region highly vulnerable to climate change effects, including sea-level rise.
WWF is trying to link abundant but scattered existing resources, databases, and information sources within the Insular Caribbean to assess their validity, usefulness and accessibility aiming at the future development and implementation of a climate change-related ecosystems vulnerability and adaptability action plan.
The Insular Caribbean consists of the region between North and South America comprised of three subregions: the Bahamas, the Lesser Antilles, and the Greater Antilles. This region includes 25 different countries and territories spread over more than 4 million km2 of ocean with only an estimated 230,000 km2 of land.
The Insular Caribbean is known for its rich biodiversity and high levels of endemism, yet has a long history of human exploitation resulting in a significant amount of resource degradation and depletion.
For example, 90% of the Insular Caribbean forest cover has been converted to agroscapes, over 70% of its coral reefs are threatened, mangroves deforested, and its beaches impacted, altered and squeezed by coastal development.
The Insular Caribbean islands emerge as top priority for the expansion of the global protected areas with endemically rich islands in need of preservation, and requiring biodiversity assessments, and management tools to conserve the remaining resources and create sustainability.
December 6, 2007
November 29, 2007
Oceans and CO2
Oceans are 'soaking up less CO2'
The amount of carbon dioxide being absorbed by the world's oceans has reduced, scientists have said.
University of East Anglia researchers gauged CO2 absorption through more than 90,000 measurements from merchant ships equipped with automatic instruments.
Results of their 10-year study in the North Atlantic show CO2 uptake halved between the mid-90s and 2000 to 2005.
Scientists believe global warming might get worse if the oceans soak up less of the greenhouse gas.
Researchers said the findings, published in a paper for the Journal of Geophysical Research, were surprising and worrying because there were grounds for believing that, in time, the ocean might become saturated with our emissions.
'Saturated' ocean
BBC environment analyst Roger Harrabin said: "The researchers don't know if the change is due to climate change or to natural variations.
"But they say it is a tremendous surprise and very worrying because there were grounds for believing that in time the ocean might become 'saturated' with our emissions - unable to soak up any more."
He said that would "leave all our emissions to warm the atmosphere".
Of all the CO2 emitted into the atmosphere, only half of it stays there; the rest goes into carbon sinks.
There are two major carbon sinks in the biological cycle: the oceans and the land "biosphere", which includes plants and the soil.
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/uk_news/7053903.stm
Published: 2007/10/20 04:50:45 GMT
© BBC MMVII
The amount of carbon dioxide being absorbed by the world's oceans has reduced, scientists have said.
University of East Anglia researchers gauged CO2 absorption through more than 90,000 measurements from merchant ships equipped with automatic instruments.
Results of their 10-year study in the North Atlantic show CO2 uptake halved between the mid-90s and 2000 to 2005.
Scientists believe global warming might get worse if the oceans soak up less of the greenhouse gas.
Researchers said the findings, published in a paper for the Journal of Geophysical Research, were surprising and worrying because there were grounds for believing that, in time, the ocean might become saturated with our emissions.
'Saturated' ocean
BBC environment analyst Roger Harrabin said: "The researchers don't know if the change is due to climate change or to natural variations.
"But they say it is a tremendous surprise and very worrying because there were grounds for believing that in time the ocean might become 'saturated' with our emissions - unable to soak up any more."
He said that would "leave all our emissions to warm the atmosphere".
Of all the CO2 emitted into the atmosphere, only half of it stays there; the rest goes into carbon sinks.
There are two major carbon sinks in the biological cycle: the oceans and the land "biosphere", which includes plants and the soil.
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/uk_news/7053903.stm
Published: 2007/10/20 04:50:45 GMT
© BBC MMVII
November 8, 2007
Changing Ocean, Arctic Humpbacks
http://www.adn.com/news/alaska/story/9438455p-9350294c.html
Humpback, fin whales observed in the Arctic Ocean
OUT OF USUAL RANGE: Federal officials say it's too early to determine a cause.
By DAN JOLING
The Associated Press
(Published: November 8, 2007)
Endangered humpback whales swam into the Beaufort Sea off Alaska's northern coast this summer, far beyond their usual range, but federal officials monitoring the waters say it's too soon to determine if it's a trend or an anomaly.
Environmental groups say the presence of humpbacks hundreds of miles north of their usual habitat is probably another sign of the effects of global warming and the shifting Arctic ecosystem. They are calling for more study of the endangered animals' habits before industrial activity is allowed to expand off Alaska's northern shores.
Robin Cacy, a spokeswoman for the federal Minerals Management Service, which oversees lease sales for offshore petroleum drilling in federal waters, confirmed that humpback whales were spotted in the Beaufort Sea east of Barrow, the northernmost community in the United States. Humpback whales were seen in the Chukchi Sea off Alaska's northwest coast last year, she said.
Also, endangered fin whales were detected this summer by acoustic monitoring north of the Bering Strait in the Chukchi Sea, Cacy said. The fin whales were recorded as far north as Point Lay, a coastal Inupiat Eskimo village of 235 about 700 miles northwest of Anchorage.
Some of the whales were spotted by observers involved with the oil industry. Shell Exploration and Production and its contractors performed seismic work this summer in anticipation of bidding on leases. Lease sales are scheduled for 2008 in the Chukchi Sea and 2009 in the Beaufort Sea.
UNEXPECTED SIGHTINGS
No one was expecting humpbacks near the activity connected to Outer Continental Shelf lease sales, said Brad Smith, a protective resources biologist for the National Marine Fisheries Service.
"We expected those to be farther south and west of the OCS planning areas," Smith said. "We didn't anticipate that they'd been encountered in any of the OCS exploration activity that we're doing this year."
Brendan Cummings, ocean programs director for the Center for Biological Diversity, said the sightings may be an indication of a recovering humpback population expanding its range or of desperate animals in search of food.
Other species that use the Chukchi Sea, from walrus congregating on Alaska's northwest shore to gray whales seeking new feeding areas, are behaving differently because of climate change, he said.
"It looks like the populations are suffering from it," he said. "All signs point to global warming. That would be the first suspect of why the whales are there."
Deborah Williams, a former Department of Interior special assistant for Alaska, and now an advocate for finding solutions to climate change, said the presence of humpback and fin whales so far north has significant implications for the animals' management and development.
"We now have even more compelling reasons to protect the Arctic Ocean and the species dramatically affected by climate change," she said.
RECORD LOW PACK ICE
Sheela McLean, spokeswoman for the National Oceanic and Atmospheric Administration's fisheries service in Juneau, said humpbacks range widely and have been spotted on the Russian part of the Chukchi Sea. However, humpbacks are not usually associated with pack ice, so sightings farther north might be shifts in distribution caused by climate change, she said.
This year was a record low year for pack ice. The National Snow and Ice Data Center at the University of Colorado at Boulder in September recorded 1.65 million square miles of sea ice. That's 39 percent below the long-term average from 1979 to 2000.
Gary Strasburg, a spokesman for the Minerals Management Service in Washington, D.C., said a sighting of an endangered species in a new area would not mean an immediate change in how the agency regulates petroleum exploration. The agency would determine whether the presence of humpbacks was a trend, and if so, determine the appropriate response, he said.
Federal laws allow a certain level of "harassment" of marine mammals, Smith said. Permits issued in 2007 for exposure of marine mammals to noise from seismic activities covered neither humpback nor fin whales, he said.
"They do, however, have authorization to harass other whales and marine mammals, which were expected to be encountered during the course of their seismic operations," Smith said, including ringed seals, bearded seals, gray whales and bowhead whales.
Conditions imposed upon exploration for humpbacks may be no different than what's in place now, Smith said. The sensitivity of bowhead whales, which remain close to sea ice and are hunted in limited numbers by Eskimo whalers, is considered equal to or greater than the sensitivity of humpbacks, he said.
Cummings does not agree with that assessment of humpbacks -- or with the government's protective measures in general.
"These are animals that are entirely dependent on sound," he said of humpbacks.
"We don't believe that permits issued to date in the Beaufort Sea comply with the spirit or the letter of the Marine Mammal Protection Act or the Endangered Species Act," he said.
Humpback, fin whales observed in the Arctic Ocean
OUT OF USUAL RANGE: Federal officials say it's too early to determine a cause.
By DAN JOLING
The Associated Press
(Published: November 8, 2007)
Endangered humpback whales swam into the Beaufort Sea off Alaska's northern coast this summer, far beyond their usual range, but federal officials monitoring the waters say it's too soon to determine if it's a trend or an anomaly.
Environmental groups say the presence of humpbacks hundreds of miles north of their usual habitat is probably another sign of the effects of global warming and the shifting Arctic ecosystem. They are calling for more study of the endangered animals' habits before industrial activity is allowed to expand off Alaska's northern shores.
Robin Cacy, a spokeswoman for the federal Minerals Management Service, which oversees lease sales for offshore petroleum drilling in federal waters, confirmed that humpback whales were spotted in the Beaufort Sea east of Barrow, the northernmost community in the United States. Humpback whales were seen in the Chukchi Sea off Alaska's northwest coast last year, she said.
Also, endangered fin whales were detected this summer by acoustic monitoring north of the Bering Strait in the Chukchi Sea, Cacy said. The fin whales were recorded as far north as Point Lay, a coastal Inupiat Eskimo village of 235 about 700 miles northwest of Anchorage.
Some of the whales were spotted by observers involved with the oil industry. Shell Exploration and Production and its contractors performed seismic work this summer in anticipation of bidding on leases. Lease sales are scheduled for 2008 in the Chukchi Sea and 2009 in the Beaufort Sea.
UNEXPECTED SIGHTINGS
No one was expecting humpbacks near the activity connected to Outer Continental Shelf lease sales, said Brad Smith, a protective resources biologist for the National Marine Fisheries Service.
"We expected those to be farther south and west of the OCS planning areas," Smith said. "We didn't anticipate that they'd been encountered in any of the OCS exploration activity that we're doing this year."
Brendan Cummings, ocean programs director for the Center for Biological Diversity, said the sightings may be an indication of a recovering humpback population expanding its range or of desperate animals in search of food.
Other species that use the Chukchi Sea, from walrus congregating on Alaska's northwest shore to gray whales seeking new feeding areas, are behaving differently because of climate change, he said.
"It looks like the populations are suffering from it," he said. "All signs point to global warming. That would be the first suspect of why the whales are there."
Deborah Williams, a former Department of Interior special assistant for Alaska, and now an advocate for finding solutions to climate change, said the presence of humpback and fin whales so far north has significant implications for the animals' management and development.
"We now have even more compelling reasons to protect the Arctic Ocean and the species dramatically affected by climate change," she said.
RECORD LOW PACK ICE
Sheela McLean, spokeswoman for the National Oceanic and Atmospheric Administration's fisheries service in Juneau, said humpbacks range widely and have been spotted on the Russian part of the Chukchi Sea. However, humpbacks are not usually associated with pack ice, so sightings farther north might be shifts in distribution caused by climate change, she said.
This year was a record low year for pack ice. The National Snow and Ice Data Center at the University of Colorado at Boulder in September recorded 1.65 million square miles of sea ice. That's 39 percent below the long-term average from 1979 to 2000.
Gary Strasburg, a spokesman for the Minerals Management Service in Washington, D.C., said a sighting of an endangered species in a new area would not mean an immediate change in how the agency regulates petroleum exploration. The agency would determine whether the presence of humpbacks was a trend, and if so, determine the appropriate response, he said.
Federal laws allow a certain level of "harassment" of marine mammals, Smith said. Permits issued in 2007 for exposure of marine mammals to noise from seismic activities covered neither humpback nor fin whales, he said.
"They do, however, have authorization to harass other whales and marine mammals, which were expected to be encountered during the course of their seismic operations," Smith said, including ringed seals, bearded seals, gray whales and bowhead whales.
Conditions imposed upon exploration for humpbacks may be no different than what's in place now, Smith said. The sensitivity of bowhead whales, which remain close to sea ice and are hunted in limited numbers by Eskimo whalers, is considered equal to or greater than the sensitivity of humpbacks, he said.
Cummings does not agree with that assessment of humpbacks -- or with the government's protective measures in general.
"These are animals that are entirely dependent on sound," he said of humpbacks.
"We don't believe that permits issued to date in the Beaufort Sea comply with the spirit or the letter of the Marine Mammal Protection Act or the Endangered Species Act," he said.
July 30, 2007
Skinny whales, warming ocean
A giant of the sea finds slimmer pickings
Gray whales are skinnier, and scientists suspect Arctic warming is the reason why
By Kenneth R. Weiss
Times Staff Writer
July 6, 2007
SAN SIMEON, CALIF. — A female gray whale labored up the coast, the bony ridge of a shoulder blade protruding from what should be the smooth, plump roundness of healthy blubber.
"That female looks a little skinny," said federal biologist Wayne Perryman, peering through his binoculars. "You can see her scapula sticking out. Yeah, she's a skinny girl."
Scientists from Mexico to the Pacific Northwest are reporting an unusually high number of scrawny whales this year for the first time since malnourishment and disease claimed a third of the gray whale population in 1999 and 2000.
So far this year, scientists haven't seen a decline in numbers, and they are not sure what's causing the whales to be so thin. But they suspect it may be the same thing that triggered the die-off eight years ago: rapid warming of Arctic waters where the whales feed. Whales depend on cocktail-shrimp-size crustaceans to bulk up for their long southerly migration. As Arctic ice recedes, fat-rich crustaceans that flourished on the Bering Sea floor are becoming scarce.
Skinny whales were first spotted this year in the protected waters of San Ignacio Lagoon in Baja California, where gray whales spend the winter breeding and nursing their calves before returning every summer to the Arctic.
That's where a team led by Steven Swartz of the National Marine Fisheries Service in Silver Spring, Md., and Jorge Urban of the Autonomous University of Baja California Sur noticed that about 10% looked more bony than blubbery, a telltale sign of malnutrition.
Instead of making steady progress during their long migrations, the whales have been stopping often to eat along the way.
They have been seen straining mysid shrimp from kelp beds off California and British Columbia, sucking up mouthfuls of sand in Santa Barbara Harbor and skimming surface waters for krill-like crustaceans all along the West Coast.
Such opportunistic feeding has its risks. Switching to new food can expose the whales to harmful parasites as well as other hazards. There have been at least two fatal accidents this spring near San Francisco's Golden Gate Bridge. Gray whales, surfacing to breathe after dining on seafloor snacks, have been ripped apart by propellers on cargo vessels.
To find food, some gray whales have been expending more energy by extending their 5,000-mile northerly migration beyond the Bering Strait into the Chukchi and Beaufort seas north of Alaska.
It used to be a rare occurrence to see gray whales off Barrow, Alaska, said Craig George, a North Slope Borough wildlife biologist since the 1970s. In recent years they have become summertime regulars, churning up mud plumes along the shoreline in search of food.
Their arrival has become an annoyance and even a navigational hazard for local Inupiat (Eskimo) subsistence hunters, who have permits to hunt bowhead whales but not grays. "A few people have been running skiffs along the coast and have hit them," George said. "During fall bowhead whale hunting season, they see a blow and divert off course — only to find it's a gray whale."
Historically, the eastern Pacific gray whales congregated every summer in the shallows of the Chirikov Basin, a place in the north Bering Sea known for its vast seafloor carpets of crustaceans called amphipods. The whales sucked in great mouthfuls, straining out the sand and mud, packing on the pounds in the few months before their long annual journey to Baja and back.
"You could practically walk across the gray whales in the Chirikov Basin in the 1980s," said Sue Moore, a former director of the National Marine Mammal Laboratory in Seattle who has conducted aerial surveys. "They were stacked up to the horizon. In 2002, I went back and everything had changed."
The carpets of crustaceans were frayed — and, in some places, gone.
Scientists first thought that the gray whale population, which had been hunted nearly to extinction in the 1930s, had simply grown too large for its primary food source and eaten more than nature could provide. Such overgrazing was thought to have been responsible for the mass die-off in 1999 and 2000 that saw the population drop from 26,600 to about 17,400.
Now scientists suspect that the climatic changes in the Bering Sea played a role in the population plunge by reducing the whale's primary food: amphipods that appear to be affected by warming temperatures and vanishing sea ice.
These amphipods grow in tubes on sandy or muddy seafloors and cannot move around like many sea creatures. They count on bits of algae to come to them, or at least close enough so they can use their antennae to pull the food into their mouths.
One source is a confetti that rains down from shaggy mats of algae that grow on the underside of ice sheets at the ocean's surface. Another is brought by ocean currents, carrying a soupy mix of algae or plankton.
Both sources have diminished or been cut off as the northern Bering Sea has undergone a shift from a seasonally ice-dominated region to more of an open ocean dotted with thin ice that is quickly broken up by storms. And the basin's waters have warmed enough to allow new types of fish to migrate north, gobbling up the amphipods or competing with them for food.
Whales are not the only animals struggling to adapt to these rapid changes. Researchers have also noticed dramatic declines in other species that feed on the bottom, such as walruses and sea ducks.
Federal scientists believe the gray whale population is holding steady at 18,000, although they are working on an updated estimate.
The population had been growing steadily until 1998, the year of a warm El Niño now seen as a turning point for the Bering Sea's amphipod beds. Since then, the annual tally of calves has fluctuated. This year's was one of the lowest since the federal government began keeping track in 1994.
"The gray whales don't seem as robust as they once were," said Perryman, a National Marine Fisheries Service scientist in charge of the annual count of gray whale cows and calves.
He and his crew keep watch 12 hours a day from March to June tallying each gray whale that passes by the Piedras Blancas Lighthouse near San Simeon's Hearst Castle on California's Central Coast. Perryman believes that the number of calves plunges when whales do not get enough to eat.
The loss of Bering Sea feeding grounds is responsible for another trend: An increasing number of whales don't bother heading that far north. Some stop at Alaska's Kodiak Island. Others don't get even that far and spend summers near British Columbia's Vancouver Island or off the Oregon coast. Smaller groups remain off California, feeding on shrimp in kelp beds or anything else they can scrounge.
"These animals are feeding on things that scientists haven't observed in modern times," said Bruce Mate, director of the Marine Mammal Institute at Oregon State University. "They are beginning to become more diverse in their diet because they have to."
But switching food could expose them to parasites that contribute to their emaciated condition, scientists say.
It's possible, Swartz and other researchers said, that their scrawniness is merely a temporary condition as the whales learn to adapt to a rapidly changing Arctic.
"Gray whales are good at switching prey," Swartz said. "They need to find new places to feed, because the ocean is changing on them. I hope we are watching a transition rather than a serious problem."
--
ken.weiss@latimes.com
Gray whales are skinnier, and scientists suspect Arctic warming is the reason why
By Kenneth R. Weiss
Times Staff Writer
July 6, 2007
SAN SIMEON, CALIF. — A female gray whale labored up the coast, the bony ridge of a shoulder blade protruding from what should be the smooth, plump roundness of healthy blubber.
"That female looks a little skinny," said federal biologist Wayne Perryman, peering through his binoculars. "You can see her scapula sticking out. Yeah, she's a skinny girl."
Scientists from Mexico to the Pacific Northwest are reporting an unusually high number of scrawny whales this year for the first time since malnourishment and disease claimed a third of the gray whale population in 1999 and 2000.
So far this year, scientists haven't seen a decline in numbers, and they are not sure what's causing the whales to be so thin. But they suspect it may be the same thing that triggered the die-off eight years ago: rapid warming of Arctic waters where the whales feed. Whales depend on cocktail-shrimp-size crustaceans to bulk up for their long southerly migration. As Arctic ice recedes, fat-rich crustaceans that flourished on the Bering Sea floor are becoming scarce.
Skinny whales were first spotted this year in the protected waters of San Ignacio Lagoon in Baja California, where gray whales spend the winter breeding and nursing their calves before returning every summer to the Arctic.
That's where a team led by Steven Swartz of the National Marine Fisheries Service in Silver Spring, Md., and Jorge Urban of the Autonomous University of Baja California Sur noticed that about 10% looked more bony than blubbery, a telltale sign of malnutrition.
Instead of making steady progress during their long migrations, the whales have been stopping often to eat along the way.
They have been seen straining mysid shrimp from kelp beds off California and British Columbia, sucking up mouthfuls of sand in Santa Barbara Harbor and skimming surface waters for krill-like crustaceans all along the West Coast.
Such opportunistic feeding has its risks. Switching to new food can expose the whales to harmful parasites as well as other hazards. There have been at least two fatal accidents this spring near San Francisco's Golden Gate Bridge. Gray whales, surfacing to breathe after dining on seafloor snacks, have been ripped apart by propellers on cargo vessels.
To find food, some gray whales have been expending more energy by extending their 5,000-mile northerly migration beyond the Bering Strait into the Chukchi and Beaufort seas north of Alaska.
It used to be a rare occurrence to see gray whales off Barrow, Alaska, said Craig George, a North Slope Borough wildlife biologist since the 1970s. In recent years they have become summertime regulars, churning up mud plumes along the shoreline in search of food.
Their arrival has become an annoyance and even a navigational hazard for local Inupiat (Eskimo) subsistence hunters, who have permits to hunt bowhead whales but not grays. "A few people have been running skiffs along the coast and have hit them," George said. "During fall bowhead whale hunting season, they see a blow and divert off course — only to find it's a gray whale."
Historically, the eastern Pacific gray whales congregated every summer in the shallows of the Chirikov Basin, a place in the north Bering Sea known for its vast seafloor carpets of crustaceans called amphipods. The whales sucked in great mouthfuls, straining out the sand and mud, packing on the pounds in the few months before their long annual journey to Baja and back.
"You could practically walk across the gray whales in the Chirikov Basin in the 1980s," said Sue Moore, a former director of the National Marine Mammal Laboratory in Seattle who has conducted aerial surveys. "They were stacked up to the horizon. In 2002, I went back and everything had changed."
The carpets of crustaceans were frayed — and, in some places, gone.
Scientists first thought that the gray whale population, which had been hunted nearly to extinction in the 1930s, had simply grown too large for its primary food source and eaten more than nature could provide. Such overgrazing was thought to have been responsible for the mass die-off in 1999 and 2000 that saw the population drop from 26,600 to about 17,400.
Now scientists suspect that the climatic changes in the Bering Sea played a role in the population plunge by reducing the whale's primary food: amphipods that appear to be affected by warming temperatures and vanishing sea ice.
These amphipods grow in tubes on sandy or muddy seafloors and cannot move around like many sea creatures. They count on bits of algae to come to them, or at least close enough so they can use their antennae to pull the food into their mouths.
One source is a confetti that rains down from shaggy mats of algae that grow on the underside of ice sheets at the ocean's surface. Another is brought by ocean currents, carrying a soupy mix of algae or plankton.
Both sources have diminished or been cut off as the northern Bering Sea has undergone a shift from a seasonally ice-dominated region to more of an open ocean dotted with thin ice that is quickly broken up by storms. And the basin's waters have warmed enough to allow new types of fish to migrate north, gobbling up the amphipods or competing with them for food.
Whales are not the only animals struggling to adapt to these rapid changes. Researchers have also noticed dramatic declines in other species that feed on the bottom, such as walruses and sea ducks.
Federal scientists believe the gray whale population is holding steady at 18,000, although they are working on an updated estimate.
The population had been growing steadily until 1998, the year of a warm El Niño now seen as a turning point for the Bering Sea's amphipod beds. Since then, the annual tally of calves has fluctuated. This year's was one of the lowest since the federal government began keeping track in 1994.
"The gray whales don't seem as robust as they once were," said Perryman, a National Marine Fisheries Service scientist in charge of the annual count of gray whale cows and calves.
He and his crew keep watch 12 hours a day from March to June tallying each gray whale that passes by the Piedras Blancas Lighthouse near San Simeon's Hearst Castle on California's Central Coast. Perryman believes that the number of calves plunges when whales do not get enough to eat.
The loss of Bering Sea feeding grounds is responsible for another trend: An increasing number of whales don't bother heading that far north. Some stop at Alaska's Kodiak Island. Others don't get even that far and spend summers near British Columbia's Vancouver Island or off the Oregon coast. Smaller groups remain off California, feeding on shrimp in kelp beds or anything else they can scrounge.
"These animals are feeding on things that scientists haven't observed in modern times," said Bruce Mate, director of the Marine Mammal Institute at Oregon State University. "They are beginning to become more diverse in their diet because they have to."
But switching food could expose them to parasites that contribute to their emaciated condition, scientists say.
It's possible, Swartz and other researchers said, that their scrawniness is merely a temporary condition as the whales learn to adapt to a rapidly changing Arctic.
"Gray whales are good at switching prey," Swartz said. "They need to find new places to feed, because the ocean is changing on them. I hope we are watching a transition rather than a serious problem."
--
ken.weiss@latimes.com
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