An extended stay for five transient killer whales in South Sound entered its fourth week Monday amid reports that some boaters are violating guidelines for viewing the mighty marine mammals.
“I saw a couple of boats following them last night,” Eld Inlet resident Kim Merriman said Monday. “It looked like they were herding them.”
Merriman, who has seen the five orcas several times in Eld Inlet since early September, said she also has seen boaters position themselves closer than the 100-yard distance that federal officials and conservation groups recommend boaters keep between their boats and whales.
Harassing or harming marine mammals violates the federal Marine Mammal Protection Act. Violators could be subjected to a $10,000 civil violation, a criminal penalty of $100,000 or one year in prison, according to the National Marine Fisheries Service.
NMFS has proposed turning the guidelines into rules and to expand the “no-go” distance to 200 yards, said Lynne Barre, an NMFS marine mammal specialist.
The new regulation would apply to Puget Sound resident orcas, which are listed as endangered under the federal Endangered Species Act and also protected by the Marine Mammal Protection Act, as well as the transient killer whales, which are protected by the federal marine mammal law.
Human disturbance can interfere with a killer whale’s ability to hunt, feed, communicate, socialize, rest, breed or care for its young, marine mammal scientists say.
For the marine mammal-eating transients, human disturbance could hinder their ability to echolocate and hunt their prey, said Robin Baird, a research biologist with Cascadia Research Collective in Olympia.
On Sunday, Baird and fellow researcher Brad Hanson of the federal Northwest Fisheries Science Center used a dart to place a satellite tag on the dorsal fin of one of the five South Sound transient orcas they encountered off the east side of Anderson Island.
The pack of whales includes two mothers and three offspring. The whales have been spotted feeding on harbor seals during their South Sound journey. By comparison, the Puget Sound resident population feeds on fish.
The tag transmits signals 16 hours a day and requires an orbiting satellite to be overhead and the whale to be on the surface of the water to register a reading.
Tagging of several other transient killer whales in the past year has confirmed they can travel long distances in a short time – from Oregon to southeast Alaska in a matter of weeks.
Occasionally, a family or a small group of transients will hone in on one marine area for an extended stay, including nearly a six-month visit to Hood Canal by six transient killer whales in 2005.
Merriman said the current South Sound visitors have put on quite a show in front of her Eld Inlet home, frolicking on the surface, jumping out of the water and slapping their tails.
“We’re blessed to have them here,” Merriman said.
dinsdag 22 september 2009
woensdag 16 september 2009
Killer Whales Die Without King Salmon
Some killer whale populations favor king salmon so much that the whales will actually die when numbers of this largest member of the salmon family drop, according to new research.
The study, published in the latest Royal Society Biology Letters, suggests that although killer whales may consume a variety of fish species and mammals, many are highly specialized hunters dependent on this single salmon species.
Lead author John Ford explained to Discovery News that "nutritional stress" probably leads to killer whale deaths because it can make the whales "susceptible to other factors leading to mortality, such as disease and parasitism," and possibly also more vulnerable to the "immuno-suppressive effects of PCBs" and other ocean pollutants.
Ford, a research scientist at Fisheries and Oceans Canada, and his colleagues used 25 years of demographic data from two populations of fish-eating killer whales in the northeastern Pacific Ocean, along with data on numbers of chum and Chinook salmon, commonly known as king salmon.
The data consisted of annual photo ID censuses for the whales and Pacific Salmon Commission population estimates for the fish.
The scientists determined that from 1974 to the mid 1990's, resident killer whale populations steadily grew in number at an increase of nearly 2.6 percent per year. That pattern abruptly ended in the mid 1990's, when both analyzed populations of killer whales entered a period of prolonged decline, dropping by up to 17 percent as of 2001. By 2004, the populations began to recover and show growth again.
The study, published in the latest Royal Society Biology Letters, suggests that although killer whales may consume a variety of fish species and mammals, many are highly specialized hunters dependent on this single salmon species.
Lead author John Ford explained to Discovery News that "nutritional stress" probably leads to killer whale deaths because it can make the whales "susceptible to other factors leading to mortality, such as disease and parasitism," and possibly also more vulnerable to the "immuno-suppressive effects of PCBs" and other ocean pollutants.
Ford, a research scientist at Fisheries and Oceans Canada, and his colleagues used 25 years of demographic data from two populations of fish-eating killer whales in the northeastern Pacific Ocean, along with data on numbers of chum and Chinook salmon, commonly known as king salmon.
The data consisted of annual photo ID censuses for the whales and Pacific Salmon Commission population estimates for the fish.
The scientists determined that from 1974 to the mid 1990's, resident killer whale populations steadily grew in number at an increase of nearly 2.6 percent per year. That pattern abruptly ended in the mid 1990's, when both analyzed populations of killer whales entered a period of prolonged decline, dropping by up to 17 percent as of 2001. By 2004, the populations began to recover and show growth again.
zondag 13 september 2009
Humpback attacked by killer whales
A BADLY scarred juvenile humpback whale has washed up on to one of Perth's most popular beaches.
It is believed that it had been attacked by a pod of killer whales.
The seven-metre male, weighing up to seven tonnes, struggled and spouted spray and washed up three times on City Beach in Perth's west today.
Its struggle was compounded by the fact that the waves were breaking directly on to the shore, described as a shorebreak
The West Australian environment department's senior marine wildlife officer, Doug Coughran, said the one-year-old male had twice managed to get back out to sea after being washed up on the beach at about 7am.
But it was "wasting a lot of energy and for the first time in its life, is feeling its weight", Mr Coughran said.
He said it would probably have to be put down.
It had probably been migrating north when it was attacked by a pod of killer whales in an encounter that left it badly scarred from head to tail, he said
It was unlikely the whale would again manage to get back out to sea but any attempt to help it or euthanase it was too dangerous while the whale was struggling in a heavy shore break, Mr Coughran said.
He said while he and other onlookers were disturbed by the whale's obvious suffering, its beaching was probably a good sign since it indicated increasing humpback whale numbers off the West Australian coast.
"There have been a few beachings like this lately in and around Perth," Mr Coughran said.
"It could well mean there are greater numbers of whales out there."
It is believed that it had been attacked by a pod of killer whales.
The seven-metre male, weighing up to seven tonnes, struggled and spouted spray and washed up three times on City Beach in Perth's west today.
Its struggle was compounded by the fact that the waves were breaking directly on to the shore, described as a shorebreak
The West Australian environment department's senior marine wildlife officer, Doug Coughran, said the one-year-old male had twice managed to get back out to sea after being washed up on the beach at about 7am.
But it was "wasting a lot of energy and for the first time in its life, is feeling its weight", Mr Coughran said.
He said it would probably have to be put down.
It had probably been migrating north when it was attacked by a pod of killer whales in an encounter that left it badly scarred from head to tail, he said
It was unlikely the whale would again manage to get back out to sea but any attempt to help it or euthanase it was too dangerous while the whale was struggling in a heavy shore break, Mr Coughran said.
He said while he and other onlookers were disturbed by the whale's obvious suffering, its beaching was probably a good sign since it indicated increasing humpback whale numbers off the West Australian coast.
"There have been a few beachings like this lately in and around Perth," Mr Coughran said.
"It could well mean there are greater numbers of whales out there."
vrijdag 11 september 2009
Orcas may be continuing tour of South Sound
Five Transients: Animals likely those seen by residents last week
Five transient orcas were spotted patrolling the waters of South Sound on Thursday, according to reports compiled by Cascadia Research of Olympia.
“It’s highly likely they’re the same whales seen in Oakland Bay a week ago,” Cascadia marine mammal researcher John Calambokidis said.
He said the whale sightings came from several locations, including Eld Inlet, Dana Passage and Harstine Island. The whales also were seen in Budd Inlet as far south as Gull Harbor, Ralph Munro said.
Unlike the resident Puget Sound orcas, which feed on fish and are listed as an endangered species under the federal Endangered Species Act, the transient orcas, which roam the waters from Alaska to Mexico in small groups, eat marine mammals and aren’t listed as endangered.
Three transient orcas last were seen in South Sound near Fox Island in May, Calambokidis said.
“I’d characterize their appearance here in South Sound as periodic – every one to two years, on average,” he said.
Six transients paid an extended visit to Hood Canal from late January to late spring 2005, a world-record stay in one place, according to marine mammal biologists. That came on the heels of a two-month extended visit to Hood Canal by 11 transient killer whales in 2003.
The 2003 Hood Canal visitors included T-14, a whale present in Budd Inlet in 1976 during the controversial, and last, capture of killer whales in Puget Sound for use in aquariums.
It’s not yet known whether any of the killer whales seen in South Sound this year were among the Hood Canal visitors in 2003 or 2005, Calambokidis said.
Male orcas have a life expectancy of 50 to 60 years; females have a life expectancy of 90 years.
Five transient orcas were spotted patrolling the waters of South Sound on Thursday, according to reports compiled by Cascadia Research of Olympia.
“It’s highly likely they’re the same whales seen in Oakland Bay a week ago,” Cascadia marine mammal researcher John Calambokidis said.
He said the whale sightings came from several locations, including Eld Inlet, Dana Passage and Harstine Island. The whales also were seen in Budd Inlet as far south as Gull Harbor, Ralph Munro said.
Unlike the resident Puget Sound orcas, which feed on fish and are listed as an endangered species under the federal Endangered Species Act, the transient orcas, which roam the waters from Alaska to Mexico in small groups, eat marine mammals and aren’t listed as endangered.
Three transient orcas last were seen in South Sound near Fox Island in May, Calambokidis said.
“I’d characterize their appearance here in South Sound as periodic – every one to two years, on average,” he said.
Six transients paid an extended visit to Hood Canal from late January to late spring 2005, a world-record stay in one place, according to marine mammal biologists. That came on the heels of a two-month extended visit to Hood Canal by 11 transient killer whales in 2003.
The 2003 Hood Canal visitors included T-14, a whale present in Budd Inlet in 1976 during the controversial, and last, capture of killer whales in Puget Sound for use in aquariums.
It’s not yet known whether any of the killer whales seen in South Sound this year were among the Hood Canal visitors in 2003 or 2005, Calambokidis said.
Male orcas have a life expectancy of 50 to 60 years; females have a life expectancy of 90 years.
donderdag 10 september 2009
Killer Whales Strain to "Talk" Over Ship Noise?
Killer whales raise their voices to be heard over boat noise, and the effort may be wearing the whales out as they try to find food amid dwindling numbers of salmon, new research says.
The killer whales of Puget Sound make more calls and clicks while foraging than while traveling, suggesting that such mealtime conservations are key to coordinating hunts, the work reveals
Several types of vessels, from small whale-watching boats to large cruise ships, also traverse the coastal waters off Washington State and neighboring British Columbia, Canada.
"[The killer whales'] call exchange is incredibly important … and vessel noises have the potential to mask these calls," said research leader Marla Holt of Seattle's Northwest Fisheries Science Center, which is run by the National Oceanic and Atmospheric Administration (NOAA).
Holt and colleagues' previous research had shown that some killer whales make louder calls to be heard over vessel rumblings—just as people raise their voices to talk over the din of a cocktail party.
Now the researchers think the cacophony could be causing the region's killer whales to use up more energy during hunts, even as their preferred prey, chinook salmon, are on the decline.
Killer Whales' Mysterious Drop
In Puget Sound a small group of killer whales known as the Southern Residents has been found to be particularly well-suited to eating salmon—even down to the whales' tooth size.
These animals don't eat seals or other mammals, as do the transient killer whales that migrate through the sound.
In the mid- to late 1990s the Southern Resident population mysteriously shrank by nearly 20 percent, from 97 to 88 animals. Today there are 85 individuals.
In 2005 the federal government listed the population as endangered under the U.S. Endangered Species Act.
No one knows for sure, but the cause was likely a combination of fewer salmon, exposure to toxic contaminants, and vessel noise, according to Lynne Barre of NOAA's National Marine Fisheries Service Northwest Regional Office.
Barre's agency released a recovery plan for the dwindling mammals in early 2008, with the goal of boosting the population by about 2 percent a year over 28 years
Part of that plan involves monitoring the effects of vessel traffic on killer whales.
Social Calls
Killer whales are social animals that live in tight-knit pods of about 20 to 40 individuals, and they rely on calls that are "group badges" unique to each pod, she said.
Since 2007 Holt and colleagues have been recording vessel noise with underwater hydrophones off the San Juan Islands. The team records about 3,280 feet (1,000 meters) away from a group of whales then notes the animals' behaviors—foraging, traveling, resting, or socializing—every ten minutes.
Holt, who will present the team's preliminary findings in October at the Biennial Conference on the Biology of Marine Mammal in Quebec, said that their research indicates killer whale communication is particularly important during hunting.
What's more, previous studies in birds had suggested that the animals consume more oxygen to raise their voices above ambient noise, making their metabolic rates spike and burning up stored energy, Holt said.
It's possible the same phenomenon could be occurring with killer whales, although it's too early to know for sure, she added.
Keep Your Distance
Holt's work adds to existing data that have already prompted NOAA to propose a new killer whale protection law that would make all boats keep at least 600 feet (200 yards) away from the animals around Washington State.
The existing law allows boats to approach as close as 300 feet (100 yards), and some research has shown this influences the whales' behavior.
"A lot of people would argue, Why focus on these vessel regulations?" Holt said. "But it's one thing we can do immediately."
But Ken Balcomb, director of the Center for Whale Research in Friday Harbor, called the proposed law a "feel-good thing."
Balcomb, who has also studied whales in the San Juan Islands, said that "my observations over 35 years [are] that [whales] don't really get disturbed by anything, much less vessels."
No Salmon, No Whales
The main concern, Balcomb said, is the decline in chinook salmon, particularly those of the Fraser River in Canada. That salmon run has declined precipitously in recent years.
Dams on rivers in the Pacific Northwest, as well as housing developments built in estuaries where young salmon take refuge, have devastated the once abundant fish.
Researchers have already seen that bad salmon years—when fewer fish make their way downriver into Puget Sound—usually become bad whale years.
"If you deny them the food, [there's] basically no point in worrying about other factors," Balcomb said.
NOAA's Barre noted that the federal whale-recovery plan also supports efforts to revive the salmon runs that reach Puget Sound.
For instance, conservationists in the region have been working to remove dams to boost salmon populations, a strategy that has been successful with Atlantic salmon on the U.S. East Coast.
But if the fish don't come back, the Southern Residents may eventually abandon Puget Sound—a sad prospect to Balcomb.
"We like to see them here," he said. "It's the icon of our healthy ecosystem."
The killer whales of Puget Sound make more calls and clicks while foraging than while traveling, suggesting that such mealtime conservations are key to coordinating hunts, the work reveals
Several types of vessels, from small whale-watching boats to large cruise ships, also traverse the coastal waters off Washington State and neighboring British Columbia, Canada.
"[The killer whales'] call exchange is incredibly important … and vessel noises have the potential to mask these calls," said research leader Marla Holt of Seattle's Northwest Fisheries Science Center, which is run by the National Oceanic and Atmospheric Administration (NOAA).
Holt and colleagues' previous research had shown that some killer whales make louder calls to be heard over vessel rumblings—just as people raise their voices to talk over the din of a cocktail party.
Now the researchers think the cacophony could be causing the region's killer whales to use up more energy during hunts, even as their preferred prey, chinook salmon, are on the decline.
Killer Whales' Mysterious Drop
In Puget Sound a small group of killer whales known as the Southern Residents has been found to be particularly well-suited to eating salmon—even down to the whales' tooth size.
These animals don't eat seals or other mammals, as do the transient killer whales that migrate through the sound.
In the mid- to late 1990s the Southern Resident population mysteriously shrank by nearly 20 percent, from 97 to 88 animals. Today there are 85 individuals.
In 2005 the federal government listed the population as endangered under the U.S. Endangered Species Act.
No one knows for sure, but the cause was likely a combination of fewer salmon, exposure to toxic contaminants, and vessel noise, according to Lynne Barre of NOAA's National Marine Fisheries Service Northwest Regional Office.
Barre's agency released a recovery plan for the dwindling mammals in early 2008, with the goal of boosting the population by about 2 percent a year over 28 years
Part of that plan involves monitoring the effects of vessel traffic on killer whales.
Social Calls
Killer whales are social animals that live in tight-knit pods of about 20 to 40 individuals, and they rely on calls that are "group badges" unique to each pod, she said.
Since 2007 Holt and colleagues have been recording vessel noise with underwater hydrophones off the San Juan Islands. The team records about 3,280 feet (1,000 meters) away from a group of whales then notes the animals' behaviors—foraging, traveling, resting, or socializing—every ten minutes.
Holt, who will present the team's preliminary findings in October at the Biennial Conference on the Biology of Marine Mammal in Quebec, said that their research indicates killer whale communication is particularly important during hunting.
What's more, previous studies in birds had suggested that the animals consume more oxygen to raise their voices above ambient noise, making their metabolic rates spike and burning up stored energy, Holt said.
It's possible the same phenomenon could be occurring with killer whales, although it's too early to know for sure, she added.
Keep Your Distance
Holt's work adds to existing data that have already prompted NOAA to propose a new killer whale protection law that would make all boats keep at least 600 feet (200 yards) away from the animals around Washington State.
The existing law allows boats to approach as close as 300 feet (100 yards), and some research has shown this influences the whales' behavior.
"A lot of people would argue, Why focus on these vessel regulations?" Holt said. "But it's one thing we can do immediately."
But Ken Balcomb, director of the Center for Whale Research in Friday Harbor, called the proposed law a "feel-good thing."
Balcomb, who has also studied whales in the San Juan Islands, said that "my observations over 35 years [are] that [whales] don't really get disturbed by anything, much less vessels."
No Salmon, No Whales
The main concern, Balcomb said, is the decline in chinook salmon, particularly those of the Fraser River in Canada. That salmon run has declined precipitously in recent years.
Dams on rivers in the Pacific Northwest, as well as housing developments built in estuaries where young salmon take refuge, have devastated the once abundant fish.
Researchers have already seen that bad salmon years—when fewer fish make their way downriver into Puget Sound—usually become bad whale years.
"If you deny them the food, [there's] basically no point in worrying about other factors," Balcomb said.
NOAA's Barre noted that the federal whale-recovery plan also supports efforts to revive the salmon runs that reach Puget Sound.
For instance, conservationists in the region have been working to remove dams to boost salmon populations, a strategy that has been successful with Atlantic salmon on the U.S. East Coast.
But if the fish don't come back, the Southern Residents may eventually abandon Puget Sound—a sad prospect to Balcomb.
"We like to see them here," he said. "It's the icon of our healthy ecosystem."
dinsdag 1 september 2009
Dead or perhaps stranded killer whale calf sought
On Sunday, August 30th a private boater broadcast a report over the marine radio, Channel 16, that they had discovered what appeared to be a killer whale calf floating off of Lawrence Point near Orcas Island. The observer stated that the placenta was still attached to the carcass.
The Friday Harbor sheriff's office heard the broadcast and passed the information on to the San Juan County Marine Mammal Stranding Network. A fishing tender also picked up the information and notified the Network's Coordinator, Amy Traxler.
"The captain of the vessel called Traxler of The Whale Museum at home on Sunday morning, saying they had received the coordinates of the (supposed) carcass and were almost at that location," says Traxler. "He offered to look for the carcass and proceeded to do so for over an hour in pea soup fog with no luck." Traxler also searched the area for several hours Sunday afternoon but found nothing.
Even though the Network does receive periodic calls of dead whales, they usually turn out to be porpoise. Last year, however, a killer whale calf did wash up in Open Bay on Henry Island. Unfortunately, it wasn't reported until several days later and the carcass was too decomposed to get much information out of it. DNA tests did determine that it was an aborted fetus from a member of the Southern Resident Community.
"Retrieving carcasses of killer whales is rare and invaluable," said Joe Gaydos, Chief Scientist at the SeaDoc Society and the Network's veterinarian. "Only approximately 10% of the carcasses from Southern Resident killer whales are ever found which makes it difficult for us to determine the role that disease could be playing in slowing the recovery of this population."
If anyone finds this carcass, please call the Stranding Network immediately at 1-800-562-8832 and leave a message. Traxler also recommends if the carcass is found floating to tie a fender or some object to the carcass to make it easier to find.
The Friday Harbor sheriff's office heard the broadcast and passed the information on to the San Juan County Marine Mammal Stranding Network. A fishing tender also picked up the information and notified the Network's Coordinator, Amy Traxler.
"The captain of the vessel called Traxler of The Whale Museum at home on Sunday morning, saying they had received the coordinates of the (supposed) carcass and were almost at that location," says Traxler. "He offered to look for the carcass and proceeded to do so for over an hour in pea soup fog with no luck." Traxler also searched the area for several hours Sunday afternoon but found nothing.
Even though the Network does receive periodic calls of dead whales, they usually turn out to be porpoise. Last year, however, a killer whale calf did wash up in Open Bay on Henry Island. Unfortunately, it wasn't reported until several days later and the carcass was too decomposed to get much information out of it. DNA tests did determine that it was an aborted fetus from a member of the Southern Resident Community.
"Retrieving carcasses of killer whales is rare and invaluable," said Joe Gaydos, Chief Scientist at the SeaDoc Society and the Network's veterinarian. "Only approximately 10% of the carcasses from Southern Resident killer whales are ever found which makes it difficult for us to determine the role that disease could be playing in slowing the recovery of this population."
If anyone finds this carcass, please call the Stranding Network immediately at 1-800-562-8832 and leave a message. Traxler also recommends if the carcass is found floating to tie a fender or some object to the carcass to make it easier to find.
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