January 4th, 2010
Annual Southern Resident Killer Whale population count reported to US National Marine Fisheries Service.
The Endangered Southern Resident Killer Whale (SRKW) population increased in 2009 to 87 individuals as of December 31, 2009, a net increase of two during a year in which three resident whales are missing and five were born. Three of the new babies were born into J pod, the most frequently observed of the three pods (J, K, and L) that frequent the Pacific Northwest inland marine waters of the Salish Sea. No sooner had the census report been made to the government than another new baby killer whale appeared in J pod, this one to a twelve year old female on 3 January 2010! For the time being, that means the SRKW population is back up to 88! We are optimistic that this “baby boom” in J pod represents a comeback for the resident population that went into steep decline in the mid 1990’s. Now, their survival and continued population recovery depends upon sufficient food supplies (wild salmon, particularly Chinook) in future years in this region. The whales are traveling as far as California and Haida Gwai (Queen Charlotte Islands) searching for these nutritious fish, but they keep coming back to the Salish Sea. If the whales could talk to us, they would probably say that our effort to promote wild salmon recovery in the Pacific Northwest is good for all of us, so lets do all that we can. And, lets clean up the pollution, too, so we can all eat healthy fish.
maandag 4 januari 2010
donderdag 24 december 2009
Wildlife researchers are proposing the creation of a unique, miniature conservation zone encompassing a key feeding area for a critically endangered population of killer whales near Vancouver Island.
The international team of scientists, includingUniversity of British Columbia biologist Rob Williams and colleagues from Britain and the United States, spent four months in the summer of 2006 painstakingly monitoring the movements of a three-pod population of killer whales in waters off B.C. and Washington state that numbers just 87 individuals -- so few that every animal has been identified from distinctive markings.
The researchers found the whales were about three times more likely to feast on Chinook salmon -- their preferred meal -- in a narrow coastal strip south of Washington's San Juan Island than anywhere else in their summer range.
In an article published in the latest issue of the journal Animal Conservation, the scientists propose strict protections for this whale-dining "hot spot," arguing that the no-go zone is small enough to establish a practical system for diverting boat traffic but
large enough to guarantee the whales unfettered feeding.
"Protecting even small patches of water can provide conservation benefits, as long as we choose the spots wisely," said lead researcher Erin Ashe, a biologist at Scotland's University of St Andrews, in a summary of the study.
Ms. Ashe and Mr. Williams said a sanctuary created in 1982 at the north end of Vancouver Island-- the Robson Bight Ecological Reserve -- has successfully protected an area where killer whales in a different population gather to rub their bodies on pebbled beaches.
The proposed Marine Protected Area (MPA) near San Juan Island -- a rectangular zone measuring about two kilometres by 12 kilometres -- would be the first reserve designed specifically to prevent human disturbance of a killer whale feeding ground.
The research team noted that creating a quiet environment is particularly important because the animals' behaviour is more affected by boat traffic while hunting prey than when moving along travel corridors or engaging in other activities.
"MPAs are valuable tools for conservation, but they are not our only tool," Ms. Ashe and Mr. Williams said, emphasizing the proposed exclusion zone for boats would be set within a broader area in the U.S.-Canada boundary waters that is already designated as a conservation area for killer whales.
"A smaller conservation area that is well-placed, effectively managed and has good compliance from boaters might offer additional protection within the broader critical habitat," they said.
The researchers acknowledged that tighter restrictions on human activity in an area popular for whale-watching and recreational boating could be contentious.
"The candidate no-go zone identified in our study is currently used for ecotourism, commercial and recreational fishing, marine transportation and research, and is adjacent to international shipping lanes," they said.
"For an MPA to be successful, there has to be broad, local support, and we hope that that can be achieved here ... There will be controversy, of course, but ... there is overwhelming support for killer whale conservation in the region."
Read more: http://www.nationalpost.com/news/canada/story.html?id=2376600#ixzz0amcKvAZk
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The international team of scientists, includingUniversity of British Columbia biologist Rob Williams and colleagues from Britain and the United States, spent four months in the summer of 2006 painstakingly monitoring the movements of a three-pod population of killer whales in waters off B.C. and Washington state that numbers just 87 individuals -- so few that every animal has been identified from distinctive markings.
The researchers found the whales were about three times more likely to feast on Chinook salmon -- their preferred meal -- in a narrow coastal strip south of Washington's San Juan Island than anywhere else in their summer range.
In an article published in the latest issue of the journal Animal Conservation, the scientists propose strict protections for this whale-dining "hot spot," arguing that the no-go zone is small enough to establish a practical system for diverting boat traffic but
large enough to guarantee the whales unfettered feeding.
"Protecting even small patches of water can provide conservation benefits, as long as we choose the spots wisely," said lead researcher Erin Ashe, a biologist at Scotland's University of St Andrews, in a summary of the study.
Ms. Ashe and Mr. Williams said a sanctuary created in 1982 at the north end of Vancouver Island-- the Robson Bight Ecological Reserve -- has successfully protected an area where killer whales in a different population gather to rub their bodies on pebbled beaches.
The proposed Marine Protected Area (MPA) near San Juan Island -- a rectangular zone measuring about two kilometres by 12 kilometres -- would be the first reserve designed specifically to prevent human disturbance of a killer whale feeding ground.
The research team noted that creating a quiet environment is particularly important because the animals' behaviour is more affected by boat traffic while hunting prey than when moving along travel corridors or engaging in other activities.
"MPAs are valuable tools for conservation, but they are not our only tool," Ms. Ashe and Mr. Williams said, emphasizing the proposed exclusion zone for boats would be set within a broader area in the U.S.-Canada boundary waters that is already designated as a conservation area for killer whales.
"A smaller conservation area that is well-placed, effectively managed and has good compliance from boaters might offer additional protection within the broader critical habitat," they said.
The researchers acknowledged that tighter restrictions on human activity in an area popular for whale-watching and recreational boating could be contentious.
"The candidate no-go zone identified in our study is currently used for ecotourism, commercial and recreational fishing, marine transportation and research, and is adjacent to international shipping lanes," they said.
"For an MPA to be successful, there has to be broad, local support, and we hope that that can be achieved here ... There will be controversy, of course, but ... there is overwhelming support for killer whale conservation in the region."
Read more: http://www.nationalpost.com/news/canada/story.html?id=2376600#ixzz0amcKvAZk
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donderdag 17 december 2009
Killer whales 'body-slam' dolphins in Australia attack
Australian surfers told of their horror as they watched a pod of killer whales attack a large group of dolphins, throwing them into the air and leaping to catch them.
Jamie Kidney said he was surfing off southern Australia's Eyre Peninsula with his friend Anton Storey when the ocean erupted into a seething mass of white water and "all hell broke loose".
"(It was) just chaos, you saw monstrous amounts of white water and then dolphins go flying up in the air, a killer whale would jump out of the water, grab it and body-slam it," Kidney told state radio.
"We look up out the back and these killer whales are just ramming dolphins out of the water and grabbing them, and this just kept going on and on and on, it was unreal," added Storey.
The pair estimated there were up to 100 dolphins under attack, and Kidney said the whales appeared to be toying with the mammals for fun before killing and eating them.
South Australian biologist Cath Kemper said it was "on the unusual side" to see killer whales attack dolphins so close to shore.
"They might have come in initially to look for snapper and maybe there were some dolphins around," Kemper told AFP.
"We've certainly had other reports of killer whales attacking seals and things but not necessarily dolphins.
Sometimes called "wolves of the sea", killer whales are top-order predators that eat anything from squid to larger marine mammals, she added.
Jamie Kidney said he was surfing off southern Australia's Eyre Peninsula with his friend Anton Storey when the ocean erupted into a seething mass of white water and "all hell broke loose".
"(It was) just chaos, you saw monstrous amounts of white water and then dolphins go flying up in the air, a killer whale would jump out of the water, grab it and body-slam it," Kidney told state radio.
"We look up out the back and these killer whales are just ramming dolphins out of the water and grabbing them, and this just kept going on and on and on, it was unreal," added Storey.
The pair estimated there were up to 100 dolphins under attack, and Kidney said the whales appeared to be toying with the mammals for fun before killing and eating them.
South Australian biologist Cath Kemper said it was "on the unusual side" to see killer whales attack dolphins so close to shore.
"They might have come in initially to look for snapper and maybe there were some dolphins around," Kemper told AFP.
"We've certainly had other reports of killer whales attacking seals and things but not necessarily dolphins.
Sometimes called "wolves of the sea", killer whales are top-order predators that eat anything from squid to larger marine mammals, she added.
donderdag 10 december 2009
Gray-colored transient killer whale spotted
On December 10, 2009 Capt Jim Maya, a whale watch operator from San Juan Island, photographed this white/gray colored transient killer whale. While nobody knows for sure why this whale is colored this way, grey and albino killer whales have been reported before.
In the 1970's, an albino orca in a Canadian aquarium was diagnosed with Chediak-Higashi syndrome and this syndrome could be the reason for the lack of coloration seen in the transient photographed by Capt. Jim on December 10th. Chediak-Higashi syndrome damages the immune system, increasing an animal's susceptibility to viral and bacterial infections. More specifically, it is an inherited genetic mutation that reduces the ability of white blood cells to destroy infectious agents such as bacteria. This mutation also reduces skin pigmentation, resulting in full or partial albinism. Chediak-Higashi syndrome has also been reported in humans, mice and cattle.
Genetic, infectious, parasitic and toxic diseases can impact the recovery of endangered species like the southern resident killer whales and SeaDoc has been working with other experts around the region to study and monitor diseases in killer whales. We thank Capt. Jim of Maya Westside Charters on San Juan Island for these photographs.
In the 1970's, an albino orca in a Canadian aquarium was diagnosed with Chediak-Higashi syndrome and this syndrome could be the reason for the lack of coloration seen in the transient photographed by Capt. Jim on December 10th. Chediak-Higashi syndrome damages the immune system, increasing an animal's susceptibility to viral and bacterial infections. More specifically, it is an inherited genetic mutation that reduces the ability of white blood cells to destroy infectious agents such as bacteria. This mutation also reduces skin pigmentation, resulting in full or partial albinism. Chediak-Higashi syndrome has also been reported in humans, mice and cattle.
Genetic, infectious, parasitic and toxic diseases can impact the recovery of endangered species like the southern resident killer whales and SeaDoc has been working with other experts around the region to study and monitor diseases in killer whales. We thank Capt. Jim of Maya Westside Charters on San Juan Island for these photographs.
zaterdag 28 november 2009
Killer whales attack and eat sharks
Several populations of skilled orcas around the world have learned how to overcome sharks using a combination of superior brain power and brute force.
The Great White and Mako are just two of at least nine species of shark known to be eaten by some orca families.
Populations of orcas in territories across the globe - including New Zealand, Papua New Guinea and the Farallon Islands off America's west coast - have devised a number of strategies for tackling sharks.
But to make sure they don't end up seriously injured when attacking such dangerous prey, the orcas spend years perfecting the various techniques and watching more experienced adults demonstrate how to do it properly.
"The most impressive strategy is the 'karate chop'," said expert Dr Ingrid Visser, 43, who has studied orca behaviour for 17 years.
"The orca will use its tail to drive the shark to the surface. They don't even touch it. Using an up-thrust of its tail it creates a vortex which pushes the shark up on they current they create with their movements.
"Once the shark is at the surface, the killer whale pivots and lifts its tail out of the water and comes down on top of it like a karate chop."
The orca then grasps the shark and turns it upside down - suggesting that they may somehow understand shark biology.
When sharks are quickly flipped upside down, they enter a paralysed state known as 'tonic immobility'.
"It's not that the orca understands the physiology of the shark," said Dr Visser, from Tutukaka, North Island, New Zealand.. "But it does demonstrate that they understand the behavioural consequences of what will happen if they take a certain action.
"You don't need to understand how a car works in order to drive it. All you need to know is the individual behaviours that make the car go.
"In the same way, it seems the orcas that can do this have learned that if they turn the shark upside down, they don't fight back. They simply manipulate that to their advantage."
Other methods observed by scientists and witnesses include 'corralling', where groups of orcas circle a lone shark and ram it or stealthily approach the shark from directly below and catch it off guard by attacking its underbelly.
"They always eventually turn the shark upside down," added Dr Visser. "At that point the shark cannot fight back, it has been a successful hunt and they can feed.
"We don't think that the orcas are specifically making a decision to go out and hunt shark. The marine world can be a difficult place to find food. When there is an opportunity, an orca will take it."
Dr Visser is a leading orca researcher and has pioneered several discoveries in orca behaviour. She was the first to record orcas hunting hammerhead and thresher sharks.
See and read more about this incredible behaviour in the December issue of BBC Wildlife Magazine.
The Great White and Mako are just two of at least nine species of shark known to be eaten by some orca families.
Populations of orcas in territories across the globe - including New Zealand, Papua New Guinea and the Farallon Islands off America's west coast - have devised a number of strategies for tackling sharks.
But to make sure they don't end up seriously injured when attacking such dangerous prey, the orcas spend years perfecting the various techniques and watching more experienced adults demonstrate how to do it properly.
"The most impressive strategy is the 'karate chop'," said expert Dr Ingrid Visser, 43, who has studied orca behaviour for 17 years.
"The orca will use its tail to drive the shark to the surface. They don't even touch it. Using an up-thrust of its tail it creates a vortex which pushes the shark up on they current they create with their movements.
"Once the shark is at the surface, the killer whale pivots and lifts its tail out of the water and comes down on top of it like a karate chop."
The orca then grasps the shark and turns it upside down - suggesting that they may somehow understand shark biology.
When sharks are quickly flipped upside down, they enter a paralysed state known as 'tonic immobility'.
"It's not that the orca understands the physiology of the shark," said Dr Visser, from Tutukaka, North Island, New Zealand.. "But it does demonstrate that they understand the behavioural consequences of what will happen if they take a certain action.
"You don't need to understand how a car works in order to drive it. All you need to know is the individual behaviours that make the car go.
"In the same way, it seems the orcas that can do this have learned that if they turn the shark upside down, they don't fight back. They simply manipulate that to their advantage."
Other methods observed by scientists and witnesses include 'corralling', where groups of orcas circle a lone shark and ram it or stealthily approach the shark from directly below and catch it off guard by attacking its underbelly.
"They always eventually turn the shark upside down," added Dr Visser. "At that point the shark cannot fight back, it has been a successful hunt and they can feed.
"We don't think that the orcas are specifically making a decision to go out and hunt shark. The marine world can be a difficult place to find food. When there is an opportunity, an orca will take it."
Dr Visser is a leading orca researcher and has pioneered several discoveries in orca behaviour. She was the first to record orcas hunting hammerhead and thresher sharks.
See and read more about this incredible behaviour in the December issue of BBC Wildlife Magazine.
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