It's not quite an orca baby boom, but the latest birth of a calf, L114 — that's how science-types like to name subjects — is cause for optimism for whale researchers here.
There now have been five orca babies born in the past year in this group, which spends much of its time in the San Juans and Puget Sound.
"I wouldn't yet call it a boom, but it's exciting because every new calf born is an indication that this endangered population may be on the road to recovery," says Lynne Barre, marine-mammal specialist with National Oceanic and Atmospheric Administration Fisheries.
L114 would bring the southern resident killer-whale population to 89. It had declined to 81 in 2001, a drop of 17 percent from its high of 98 in 1995.
The new baby and mom (L77) were first reported Sunday afternoon off southern Vancouver Island by the Center for Whale Research in Friday Harbor.
Dave Ellifrit, a research assistant at the center, went out on an 18-foot inflatable motorboat, along with the center's director, Ken Balcomb, to where 11 of the whales had been spotted.
Ellifrit said he took some 300 photos of the baby whale.
By now, 20 years into whale spotting, Ellifrit says he's quite good at telling the whales apart by their dorsal fin and "saddle patches," the gray area behind the dorsal fin.
"It comes with practice, lots of pictures and seeing lots of them," he says of spotting individual whales.
He has not gotten tired of mingling with the whales. "They're the coolest things around. They're really beautiful animals," he says. "And you get to watch calves grow up, and have their own calves. You get hooked on it."
The newest baby whale still has fetal folds. Barre says having fetal folds means that while the baby was inside the mom, it was so big that its tail was folded.
A baby orca pops out at about 440 pounds and eight feet in length, Barre says.
The gestation period is 17 months, so, understandably, females give birth only every four or five years, the researcher says.
"It takes a considerable amount of maternal investment to have the pregnancy and to nurse the calf," Barre says. "It takes time to get back into condition."
Female orcas have somewhat similar patterns to humans. Females can start reproduction at age 15, be able to get pregnant until around age 40, and can live up to 80 or 90 years, Barre says.
Males don't live as long; their bodies call it quits at age 60 or 70.
The offspring stay with their moms their entire lives.
The male J1, for example, who's about 60 years old, still is with mom, J2, who is nearly 100, Barre says.
dinsdag 23 februari 2010
donderdag 4 februari 2010
Whales use 'Killer' technique for hunting fish
Scientists on Shetland believe they may have discovered a previously-unobserved technique being used by killer whales to catch herring.
Researchers from Aberdeen and St Andrews Universities recorded the whales emitting a low-pitched noise which caused the fish to bunch up.
The mammals then stun the fish with their tails before eating them.
The scientists said this behaviour has not been seen anywhere else in the world.
The findings have come to light in the BBC2 series "Simon King's Shetland Diaries".
Whale researcher, Dr Volker Deecke, demonstrated how his team used underwater microphones to record unusual sounds made by killer whales.
They included a low-pitched noise that the researchers believe caused the herring to bunch up in a tight shoal.
The whales then slap the shoal with their tails to stun the fish before killing and feeding on them.
It is only a theory at this stage and studies will resume in the summer, but the evidence is described as compelling, even though this behaviour hasn't been seen before in any orcas anywhere else in the world.
The use of a herding call was first described from Iceland by research colleagues of Dr Deecke.
However, it was believed that this hunting technique was confined to Iceland, as other killer whale populations feeding on herring did not appear to use it.
Acoustic research
Scientists said the fact that the herding call had been recorded in the waters around Shetland suggested that the large groups of killer whales seen feeding offshore are part of the Icelandic herring-feeding population.
Volker Deecke said: "It illustrates the value of doing acoustic research when trying to determine the population identity of killer whale populations.
"Even a short recording of sounds can answer questions that could take years of work using other methods such as photographic identification of individuals".
Simon King said: "There is something about the beast from the deep rising up. It is just amazing.
"These are sentient animals, with complex family structures, but being so close you really get the sense that there is so much more to these creatures than we currently know".
The research was funded by the Carnegie Trust for the Universities of Scotland with additional support from Scottish Natural Heritage and SEERAD.
Researchers from Aberdeen and St Andrews Universities recorded the whales emitting a low-pitched noise which caused the fish to bunch up.
The mammals then stun the fish with their tails before eating them.
The scientists said this behaviour has not been seen anywhere else in the world.
The findings have come to light in the BBC2 series "Simon King's Shetland Diaries".
Whale researcher, Dr Volker Deecke, demonstrated how his team used underwater microphones to record unusual sounds made by killer whales.
They included a low-pitched noise that the researchers believe caused the herring to bunch up in a tight shoal.
The whales then slap the shoal with their tails to stun the fish before killing and feeding on them.
It is only a theory at this stage and studies will resume in the summer, but the evidence is described as compelling, even though this behaviour hasn't been seen before in any orcas anywhere else in the world.
The use of a herding call was first described from Iceland by research colleagues of Dr Deecke.
However, it was believed that this hunting technique was confined to Iceland, as other killer whale populations feeding on herring did not appear to use it.
Acoustic research
Scientists said the fact that the herding call had been recorded in the waters around Shetland suggested that the large groups of killer whales seen feeding offshore are part of the Icelandic herring-feeding population.
Volker Deecke said: "It illustrates the value of doing acoustic research when trying to determine the population identity of killer whale populations.
"Even a short recording of sounds can answer questions that could take years of work using other methods such as photographic identification of individuals".
Simon King said: "There is something about the beast from the deep rising up. It is just amazing.
"These are sentient animals, with complex family structures, but being so close you really get the sense that there is so much more to these creatures than we currently know".
The research was funded by the Carnegie Trust for the Universities of Scotland with additional support from Scottish Natural Heritage and SEERAD.
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