Orca ‘apocalypse’: half of killer whales doomed to die from pollution

September 27, 2018

At least half of the world’s killer whale populations are doomed to extinction due to toxic and persistent pollution of the oceans, according to a major new study.

Although the poisonous chemicals, PCBs, have been banned for decades, they are still leaking into the seas. They become concentrated up the food chain; as a result, killer whales, the top predators, are the most contaminated animals on the planet. Worse, their fat-rich milk passes on very high doses to their newborn calves.

PCB concentrations found in killer whales can be 100 times safe levels and severely damage reproductive organs, cause cancer and damage the immune system. The new research analysed the prospects for killer whale populations over the next century and found those offshore from industrialised nations could vanish as soon as 30-50 years.

Among those most at risk are the UK’s last pod, where a recent death revealed one of the highest PCB levels ever recorded. Others off Gibraltar, Japan and Brazil and in the north-east Pacific are also in great danger. Killer whales are one of the most widespread mammals on earth but have already been lost in the North Sea, around Spain and many other places.

“It is like a killer whale apocalypse,” said Paul Jepson at the Zoological Society of London, part of the international research team behind the new study. “Even in a pristine condition they are very slow to reproduce.” Healthy killer whales take 20 years to reach peak sexual maturity and 18 months to gestate a calf.

PCBs were used around the world since the 1930s in electrical components, plastics and paints but their toxicity has been known for 50 years. They were banned by nations in the 1970s and 1980s but 80% of the 1m tonnes produced have yet to be destroyed and are still leaking into the seas from landfills and other sources.

The international Stockholm Convention on Persistent Organic Pollutants came into force in 2004 to tackle the issue, but Jepson said the clean-up is way behind schedule. “I think the Stockholm Convention is failing,” he said. “The only area where I am optimistic is the US. They alone produced 50% of all PCBs, but they have been getting PCB levels down consistently for decades. All we have done in Europe is ban them and then hope they go away.”

The researchers said PCBs are just one pollutant found in killer whales, with “a long list of additional known and as yet unmeasured contaminants present”. Further problems for killer whales include the loss of key prey species such as tuna and sharks to overfishing and also growing underwater noise pollution.

The new research, published in the journal Science, examined PCB contamination in 351 killer whales, the largest analysis yet. The scientists then took existing data on how PCBs affect calf survival and immune systems in whales and used this to model how populations will fare in the future. “Populations of Japan, Brazil, Northeast Pacific, Strait of Gibraltar, and the United Kingdom are all tending toward complete collapse,” they concluded.

Lucy Babey, deputy director at conservation group Orca, said: “Our abysmal failures to control chemical pollution ending up in our oceans has caused a killer whale catastrophe on an epic scale. It is essential that requirements to dispose safely of PCBs under the Stockholm Convention are made legally binding at the next meeting in May 2019 to help stop this scandal.” Scientists have previously found “extraordinary” levels of toxic pollution even in the 10km-deep Mariana trench in the Pacific Ocean.

“This new study is a global red alert on the state of our oceans,” said Jennifer Lonsdale, chair of the Wildlife and Countryside Link’s whales group. “If the UK government wants its [proposed] Environment Act to be world-leading, it must set ambitious targets on PCB disposal and protect against further chemical pollution of our waters.”

The research shows that killer whale populations in the high north, off Norway, Iceland, Canada and the Faroes, are far less contaminated due to their distance from major PCB sources. ”The only thing that gives me hope about killer whales in the longer term is, yes, we are going to lose populations all over the industrialised areas, but there are populations that are doing reasonably well in the Arctic,” said Jepson.

If a global clean-up, which would take decades, can be achieved, these populations could eventually repopulate empty regions, he said, noting that killer whales are very intelligent, have strong family bonds and hunt in packs. “It is an incredibly adaptive species – they have been able to [live] from the Arctic to the Antarctic and everywhere in between.”

He praised the billion-dollar “superfund” clean-ups in the US, such as in the Hudson River and Puget Sound, where the polluter has paid most of the costs: “The US is going way beyond the Stockholm Convention because they know how toxic PCBs are.”

Source: The Guardian.com

Killer whale appears in Oslo’s harbour

April 13, 2018

Norway is known, and often criticized internationally, for its annual whale hunt. This week a killer whale seemed to be seeking refuge, with an unusual appearance in Oslo’s inner harbour.

The Oslo fjord is far from the hunting grounds for the sperm whales that Norwegian whaling boats go after in waters off the northern coast. The Oslo area isn’t known for whales of any kind, but some skateboarders enjoying one of the capital’s first spring days got a surprise.

“Somebody yelled ‘there’s a seal’,” Nikolay Næss told state broadcaster NRK on Friday, He and friends were skating near the piers along Rådhusplassen (the plaza in front of City Hall) when a killer whale not only came into view but flapped its tail and blew a bit in the water alongside the jetty.

“It swam slowly and showed off in a way,” Næss told NRK. “I’ve never experienced anything like it.” He said around 15 to 20 people saw it, and he shared a video with NRK (external link, in Norwegian).

Tore Haug, a researcher at Havforskningsinstituttet in Tromsø, said killer whales are common off the sea coast but not inside the Oslo Fjord. “They mostly eat herring, but also mackerel, seal and other fish,” Haug told NRK, adding as a joke: “I don’t know what it found in the harbour basin, and it’s a bit early to go after people who are out swimming.”

He noted that killer whales also normally travel in pods and are seldom alone: “There may have been more whales that folks didn’t see.”

Source: News in English.no

Surfers in Norway have close call with pod of orcas

September 25, 2017

Surfers participating at the Lofoten Masters surf competition in Norway had an extremely close call with a pod of hungry orcas over the weekend.

During the semifinals, three orcas rushed towards the shore where a group of surfers were.

One of the surfers reported being as close as 50 centimetres from one of the whales.

According to marine biologists at Norwegian Orca Survey, the orcas were on the hunt.

“Based on the group size and behaviour, we have no doubt saying that these orcas were searching for seal prey,” they said.

One whale can be seen charging full speed at a surfer before it veers off.

“Fortunately, orcas use echolocation to better investigate their habitat and prey. It is likely that the charging orca realized, at the very last second, that the surfer was not a seal and took a sharp turn and moved away,” said Norwegian Orca Survey.

The surf competition organizers said none of the surfers or the orcas was injured.

To see the article and watch the VIDEO of the encounter visit the source at Global News.ca

Community Comes Together to Rescue 5 Wild Orcas Who Were Stuck in Shallow Waters for 19 Days

An incredible orca rescue was carried out recently by Norwegian Orca Survey in a bay off of Brønnøysund, on the central coast of Norway. It is believed the animals were trapped in the bay for as long as nineteen days, but, fortunately, that is not the case anymore.

Before the operation, the team of rescuers spent a couple of days closely investigating the group of orcas. The rescue proved to be a big undertaking in which took part 30 boats, 16 kayaks, and more than 60 people! The ships followed the animals at a safe distance in order to help them find their way out of the bay.

The cooperation and collective effort had wonderful results. After five hours, the orcas finally passed the shallow strait and swam out into the open waters.

As Norwegian Orca Survey wrote on their Facebook page, this fantastic operation not only enabled the team to rescue the lives of five orcas but was also “an incredible human experience.” The team also thanks the local community of the area for their support and for taking part in the efforts to save the orcas.

To learn more about Norwegian Orca Survey, click here.

Source: One Green Planet.org

Divers record underwater encounter with killer whales off Norway

January 25, 2017

A diver off the coast of Norway captured video footage of an unusual underwater encounter, with a pod of killer whales.

The video, posted to Instagram by user bobcatlisa, shows the diver and her companions scuba diving off Tromso, Norway, when they encounter the whales.

The black and white whales swim in a group past the humans, not appearing to notice them.

The orcas do not appear bothered when one of the human dives swims in for a closer look.

To see the VIDEO visit the source upi.com

Menopause Mystery: Why Do Female Killer Whales Experience The Change Of Life?

January 12, 2017

Menopause is a mystery to evolutionary biologists, but new insights could come from a long-term study of killer whales.

In these whales, the explanation may lie in a combination of conflict and cooperation between older and younger females, according to a report published Thursday in the journal Current Biology.

Killer whales are one of only three species known to have menopause — the others are pilot whales and humans. Researchers have long wondered why it was that these few species evolved to have females that spend so much of their lives unable to have babies.

Killer whales start reproducing around age 15, but stop having calves in their 30s or 40s, even though they can live for around a century.

A team led by behavioral ecologist Darren Croft of the University of Exeter decided to search for answers with the help of an unusual long-term study of killer whales in the Pacific Northwest. There, since the 1970s, researchers have carefully collected information on the births and deaths of individual whales that live in family groups.

Contained within the data is an intriguing clue about why female whales may stop reproducing later in life.

When older females reproduce at the same time as their daughters, who live alongside them, the calves of the older mothers are nearly twice as likely to die in the first 15 years of life. But when older mothers had calves in the absence of a reproducing daughter, their calves did just fine.

“It’s not that older mothers are bad mothers, that they’re not able to raise their calves as younger mothers,” says Croft. “It’s that when they enter into this competition with their daughters, they lose out and their calves are more likely to die.”

The competition may center on access to food, says Croft, because there’s good reason to believe older females feel more pressure to share their precious fish with the others around them.

That’s because, in killer whales, females mate with males from other groups but then rejoin their families. That means when a new calf is born, its father is not around, and females start their lives in a situation where their relatedness to the group is rather low.

As a female grows older and starts having calves that stay with her, however, she develops more kinship ties to those around her. “It may be that older females are more likely to share, and younger females are less likely to share food,” says Croft. That would mean younger females would have more resources to lavish on their own calves.

It’s clear that in these whales, older females play an important role in the survival of not just their own calves, but all of the family members they live with. “If an old female dies, her son’s risk of dying in the year following her death is over eight times higher than if his mother was still alive,” says Croft, “and these are adult sons, these are not juveniles, these are 30-year-old, fully grown males.”

The idea that older females safeguard and enhance their genetic legacy by protecting and providing for their children and grandchildren has been an influential explanation for why menopause evolved. It’s known as the Grandmother hypothesis, and was developed by anthropologists who studied hunter-gatherer cultures.

But Croft thinks that alone isn’t enough to account for menopause, because other long-lived, social species, like elephants, have older females that help their group but continue to bear young until the end of life. “Just the fact that these old females can store information and share that with the group and increase their survival doesn’t explain why they stop reproducing,” says Croft.

Proponents of the Grandmother hypothesis, however, may not be so convinced that intrafamilial conflict plays an important role.

Anthropologist Kristen Hawkes, at the University of Utah, says the killer whales are fascinating, but that they’re hard to study. “They’re doing all kinds of stuff where you can’t see it, and even to get demographic data is just so tricky, because they’re all underwater and they’re long-lived,” she says.

She points to one recent study on food-sharing in killer whales that found older females share fish with their older adult sons, perhaps to maximize the males’ ability to sire more babies.

If that’s the case, she says, “it’s not the older females and younger females in competition, it’s the older females contributing to the enormous success of their sons, and then those baby whales are all born somewhere else. They’re not competing, because their moms are elsewhere.”

Source: npr.org


September 28, 2016

Three decades of research has confirmed one thing about the appetites of Norway’s killer whales: they love Atlantic herring. The orcas here feed almost exclusively on the small, silver fish – but new drone footage proves that some rogue groups prefer a mammalian meal. Not only do the members of these unique pods hunt seals, but they also share them with each other.

This stunning footage was captured by researchers at the Norwegian Orca Survey (NOS), who are in the midst of a lengthy study that aims to crack open the habits of the region’s seal-eaters.

To be clear, orcas in other parts of the world – namely a population known as the “Transients” or “Bigg’s” in the Pacific – do eat mammals, but in Norway, this behaviour was observed for the first time only in 2014. “We finally got to capture [it],” the team wrote on Facebook. “To our knowledge, such images by drone are unique and may be a first worldwide.”

The NOS team has been watching this particular group for three years, and the emergence of drones has made that effort significantly easier. Unlike noisy research boats, the sky-high tech goes largely unnoticed by passing whales, but drones also have another leg-up on traditional, manned vessels: polarized lenses allow them to see what human eyes cannot.

“Drones enable observations of activities that may occur within the first meters below the surface, yet completely out of the observers’ sight,” write NOS researchers Eve Jourdain and Richard Karoliussen in a guest blog at ZME Science.

This is exactly what happened during the seal hunt. After a typical coastline cruise, the team noticed that the largest male in the orca group had begun to show behaviour associated with hunting (sharp turns, explosive breaths and highly arched dives), but the researchers realised what was going on only when the drone picked up the seal’s presence in the water.

“The five killer whales were persistently circling it, leaving it with no chance to escape towards the haul-outs nearby,” the researchers explain. “For a few minutes, the sea surface remained quiet. The seal may have escaped to the bottom where cavities and rocks offer hiding places. Yet killer whales are skilled top predators able to cooperatively search and handle all prey types and, eventually, the group came up back to the surface with the prey: dead.”

Then came the second surprise: the orcas proceeded to take turns at the carcass. “Food-sharing has been previously highlighted in other killer whale populations,” explain Karoliussen and Jourdain. Among fish-eating killer whales, for example, it’s common for a mother orca to hold salmon in her mouth while her calf has its fill.

Why share food? When each member of the group is fed and healthy, the pod improves its chances of landing prey, producing healthy offspring and defending each other from predators. It’s a common strategy among many terrestrial pack animals, but seeing it play out among orcas is a treat made possible by new drone technology.

“The oldest female of the group could be seen leading the [seal] carcass towards the surface and taking the first bites out,” recalls the team. “She then deliberately dropped the carcass, leaving an opportunity for the rest of the group to join the feast.” The spectacle went on for 15 minutes, during which time, five members of the pod fed from the carcass.

Source: Earth Touch News.com