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Salish Sea’s endangered killer whales studied amid quietest ocean in ‘3 or 4 decades’ – Globalnews.ca

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A significant drop in sea traffic brought on by the COVID-19 pandemic has created what scientists call a rare opportunity to study how quieter waters affect southern resident killer whales off the British Columbia coast.

Ocean Networks Canada, which has been monitoring noise from ships and sounds made by marine mammals such as orcas, said it believes the change will be a boon for the animals.

“The anticipation is that the quieter environment will help the killer whales in communicating, in socializing, in navigating and most importantly, in finding food,” said Richard Dewey, the organization’s associate director of science.

Read more:
‘Quieter ocean’ from COVID-19 could be a boon to endangered orcas, say researchers

A paper published last month in the Journal of the Acoustical Society of America said there has been about a 30 per cent decrease commercial shipping traffic into the Port of Vancouver from China due to COVID-19 in just the first four months of the year.

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Dewey said it’s not just commercial traffic that’s gone down — there’s also been a pause in whale watching boats, cruise ships, recreational vessels and tankers. That’s led to a noise reduction of
about 75 per cent, he said.

“What we are seeing in the Salish Sea is levels of shipping noise that haven’t been present for three or four decades,” he said.

“So we would have to go back to the 1980s before we would have heard such a quiet environment.”






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Quieter oceans a boon to whale researchers and orcas


Quieter oceans a boon to whale researchers and orcas

One of the major concerns for the endangered southern resident killer whales is that shipping noises have been increasing and almost doubling every decade, he said.

These mammals have a hearing that is similar to that of humans, and they communicate in a frequency band similar to ours, Dewey said.

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They use vocalizations to communicate within the pod, to navigate and most importantly to find their prey, he said.

“They echo-locate to find their salmon. It’s a very sophisticated sort of acoustic capability and the quieter the environment, they would have more success in finding prey.”

In the ocean, Dewey said whales use sound “continuously and all the time.”

READ MORE: Coronavirus: Less boat traffic is good news for Canada’s marine life

Their eyesight helps them see up to a distance of about five to 10 metres while using sounds helps them scope out kilometres, he said, adding that the Salish Sea is a “very murky environment.”

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Scientists believe the loud noises caused by humans increase stress hormones in orcas because they have to shout and cannot communicate over large distances, Dewey said.

He compared it to someone going into a loud club and having to pause until noise passes, to speak more loudly or give up.

He noted that unlike people in a club, orcas can’t just leave for a quieter space.






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New restrictions on boating around orcas off B.C. coast


New restrictions on boating around orcas off B.C. coast

Scientists will be using 30 hydrophones to record sounds made by the killer whales when they come into the Salish Sea, which should be any time now, Dewey said.

Hydrophones are underwater recording devices that record how loudly the whales talk when it’s noisy or if just give up.

The team is hoping this study will yield much-needed data to make policy and regulation changes to help the animals survive, he said.

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“If we see them returning and staying in their critical habitat for longer periods … if we have evidence of successful feeding on the salmon, then those are all good signs and in some sense the quieter environments can only have helped their survival,” he said.

READ MORE: Coronavirus: Canadians report increased wildlife sightings amid COVID-19 pandemic

The director of the University of British Columbia’s marine mammal research unit said that in the past, killer whales would be seen in the Salish Sea in May and June, but for the past four years they have been coming in much later, sometimes as late as September.

Andrew Trites said one of the reasons could be that there is not enough salmon, although mathematically there is enough fish for the 72 remaining southern resident killer whales.

This has left scientists wondering whether the trouble is that the whales cannot hunt because of disruption from vessels, he said.

“And there is an opportunity to see whether or not the behaviour of whales is different with fewer boats on the water and less noise.”

© 2020 The Canadian Press

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Beetle abundance attributed to forest fires – The Sudbury Star

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White-spotted sawyers can bite, but won’t if you don’t bug them

A white-spotted sawyer beetle, also known locally as a pine beetle.

Postmedia file photo

Beetle-mania seems to be gripping Sudbury lately as numerous black bugs with hard wings and long antennae make their presence known — and occasionally felt.

These insects — casually referred to as pine or longhorned beetles, but properly known as white-spotted sawyers — are capable of delivering a nip, although it’s not really their nature to go looking for a fight, according to a forest entomologist.

“It’s not that they are aggressive and attacking people,” says Taylor Scarr, research director of integrated pest management with the Great Lakes Forestry Centre in Sault Ste. Marie. 

“If you are a beetle on the side of a tree and a bird comes along to pick you off, the natural defence is to try to hold on with your feet and those strong mandibles,” he says. “So if you pick one up like a bird tries to pick them up, they grab your skin because that’s what they’re on, and to them they are on the trunk of a tree.”

Scarr says the beetles, distinguished by a white spot at the back of their necks, are native to Ontario and appear every year, but may be more conspicuous in Sudbury right now because of events that occurred a couple of years ago.

“Adults lay their eggs under the bark of recently dead or dying trees, and the grubs tunnel in there and come out two years afterwards,” he said. “So what we’re seeing now in the Sudbury area, I think, is all the beetles that have come out of trees that were killed in the Temagami and Parry Sound fires two years ago.”


A white-spotted sawyer beetle travels along the edge of a garage on St. Raphael Street in Sudbury.

Jim Moodie/Sudbury Star

He says beetles can travel a couple hundred kilometres to find a new food source, and those that emerged from the burnt-over areas would be quite plentiful, as the fires created a lot of good beetle habitat.

Sudburians might also be more aware of the beetles this year simply because “people are at home more” due to COVID-19, he suggests. “So they are seeing more.”

The adult beetles are about three-quarters of an inch long, sometimes as long as an inch, with antennae that can be three times as long as their bodies.

At this time of year the adults would be mating and dining on the bark of twigs in preparation for egg-laying.

“Before they lay their eggs, they do what is called maturation feeding, so they feed on the twigs of conifer trees,” says Scarr. “They need to feed on live twigs to mature the eggs.”

The bugs are awkward flyers, he notes, as they have two sets of wings. “They have hard wings that cover the abdomen and underneath that are the membraneous wings they actually fly with, so for that beetle to fly they have to lift the hard wings,” he says. “They’re cumbersome and it takes a lot of energy to fly, but they can certainly do it.”

Females have a more mottled appearance than the males, but “both have a single white spot at the base of the hard wings on the back, behind the head.”

People will sometimes confuse a female sawyer with an invasive Asian beetle, says Scarr, as both have long antennae and speckled backs, but the invader is “a bigger, more robust insect, with white markings that are much sharper.”

In China, the Asian beetle is sometimes called a “starry sky beetle,” he says, for its constellation of white spots.

Scarr says the intruder can hitchhike on wooden pallets and has been documented twice in Ontario — in the Toronto/Vaughn area in 2003, and a decade later in the Toronto/Mississauga area — but in both cases the Canadian Food Inspection Agency launched an aggressive eradication program and just last week announced that this strategy has proven successful.

Ontarians are still urged to keep an eye out for the foreign critters, however, as they can wreak much more havoc on local tree species.

“It’s a very serious pest because it likes hardwoods, and unlike the white-spotted sawyer beetle, it can attack and kill healthy trees,” says Scarr. “It has a real preference for maples, so if it were to get out and spread, it would devastate not only the hardwood industry but the maple syrup industry.”

Examples of the invasive beetle have been found recently in South Carolina, and it’s taken root in a few other U.S. states, as well as Europe, he notes.

Our homegrown sawyer beetle, meanwhile, is feared in Europe and Asia, as it carries a parasitic worm that can cause a wilt disease in their trees.


Tyler Cobb, curator of invertebrate zoology at the Royal Alberta Museum, holds a white-spotted sawyer beetle.

Larry Wong/Postmedia file photo

Here in Ontario, however, the sawyer doesn’t pose a big problem, although crews working in wildfire zones are not too keen on them. “They can drop down your shirt or coveralls while fighting a forest fire and be quite a nuisance,” notes Scarr.

In rare cases, they can also create an unpleasant shock for a homeowner who utilized air-dried lumber to frame their building.

“If the wood isn’t kiln-treated, sometimes the grubs will survive,” says Scarr. “I’ve had five or six reports where, three to four years after someone built their home, they had the beetles come out through the drywall.”

They can also be a problem at times for lumber companies if they infest trees intended for sawmills.

For the most part, though, the beetles are simply going about their business in the bush, contributing to regeneration by hastening the decomposition process.

“If a forest fire kills the trees, they can’t stand up forever and occupy the site,” says Scarr. “So the beetles come in and start to chew on the trees; fungi and other insects invade them; and eventually they rot and fall down and get replaced by something else.”

They also provide food to birds and other critters. Pileated woodpeckers, especially, seem to have a good nose — or more to the point, ear — for the grubs.

“They can hear them when they are inside a tree, just like we can, making a chewing noise,” the forest pest expert says.

The species in fact got its name for the grinding racket its teeth can make, like that of a saw passing through wood. (Sawyer, by the way, is pronounced like Tom Sawyer, the famous Mark Twain character.)

While many find the wood borers unappealing, Scarr encourages residents to try to “ignore them,” or at least tolerate them, as it won’t be long before they are done their mating and egg laying, at which point the adults begin to die off.

“You usually seem them around this time, in June and early July, but later in the summer you might just see the odd one,” he says.

In the meantime, “they don’t harm anything,” he says. “They’re just a natural part of the ecosystem.”

Anyone who has experienced the sensation of mandibles on skin may, of course, protest that “harm” is indeed something that can be inflicted by a sawyer beetle.

But even this isn’t apt to happen too often, Scarr maintains.

“I’ve handled lots and I have never been bitten,” he says. “You just have to grab them behind the head.”

jmoodie@postmedia.com

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New cadence : Going viral: Why Canadian sparrows have changed their tune – RTL Today

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Members of a Canadian sparrow species famous for their jaunty signature song are changing their tune, a curious example of a “viral phenomenon” in the animal kingdom, a study showed Thursday.

Bird enthusiasts first recorded the white-throated sparrow’s original song, with its distinctive triplet hook, in the 1950s.

Canadians even invented lyrics to accompany the ditty: “Oh my sweet, Ca-na-da, Ca-na-da, Ca-na-da.”

But starting from the late 20th century, biologists began noticing that members of the species in western Canada were innovating.

Instead of a triplet, the new song ended in a doublet and a new syncopation pattern. The new ending sounded like “Ca-na, Ca-na, Ca-na.”

Over the course of the next two decades, this new cadence became a big hit, moving eastward and conquering Alberta, then Ontario. It began entering Quebec last year.

It’s now the dominant version across more than 2,000 miles (3,000 kilometers) of territory, in an extremely rare example of the total replacement of historic bird dialect by another.

Scientist Ken Otter at the University of Northern British Columbia, and his colleague Scott Ramsay from Wilfrid Laurier University, described the dizzying pace of this transformation in the journal Current Biology.

“What we’re seeing is like somebody moving from Quebec to Paris, and all the people around them saying, ‘Wow, that’s a cool accent’ and start adopting a Quebec accent,” Otter told AFP.

Their work was based on 1,785 recordings between 2000 and 2019, the majority made by them but with contributions from citizen-scientists, who posted the files on specialist sites like xeno-canto.org.

In the western province of Alberta, about half of the recorded songs ended with the triplet in 2004; ten years later, all the males had adopted the doublet.

In 2015, half of western Canada had converted to the doublet version, and by last year, the new song had been well established on the western tip of eastern Quebec province.

At this rate, the historic triplet version may soon exist only in tape recordings.

– Bird influencers –

The males of the species sing to mark their territory, and their songs all share a common structure. Usually, if a variation appears, it remains regional and doesn’t make headway in neighboring territories.

The study represents the first time scientists have been able to show this kind spread at huge geographic scale, said Otter.

So how did it happen?

Probably in the same way that children return from summer camp humming new tunes: songbirds from different parts of Canada winter in the same parts of the United States, then return to their own homes in spring.

The researchers verified this theory by tagging a few of the birds.

So it was that in the plains of Texas and Kansas, the new song’s first adopters from western Canada — avian influencers, if you will — popularized the trend among their eastern brethren.

Previous work has shown that young birds can pick up a foreign song after listening to a recording.

But to truly understand why the males were willing to abandon the old song that had once served them well, the scientists have to rely on theories.

Otter believes it may be because females were more attracted to the new song, so young males rushed to adopt it.

“There seems to be some advantage to adding novel elements into your song that make the song, not necessarily more attractive, but increases people’s attention to it,” said Otter.

Going back to the human example, it would be akin to “if all the French women in Paris thought that a Quebec accent sounded much more interesting than a Parisian accent, and so everybody starts adopting a Quebec accent.”

The hypothesis remains unverified.

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Longhorn beetles spotted around Greater Sudbury – CBC.ca

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With summer officially underway in the region, you’re likely spending more time outside. But with that extra time outdoors, you’re likely to be sharing it with a few insects.

Recently in Sudbury, large bugs have been spotted in people’s yards. In particular, a black bug about the length of a toonie with long legs and a large antennae has been seen by many.

That bug is actually a long-horn beetle, according to entomologist and coordinator for Earthcare Sudbury Initiatives with the City of Greater Sudbury, Jennifer Babin-Fenske. 

“We do have several species of them,” she said. “Some are brown, some are black and some have different white markings.”

Babin-Fenske says that beetle is considered a “sun-loving” insect.”

“The females will lay their eggs on really hot summer days,” she said.

She adds they not only like the heat, but they’re also attracted to weakened or dead trees.

“They lay their eggs in the tree and then the larva eat their way around the wood,” she said.

“But they can be in there for about two years. Then when they emerge as adults, they still have the whole summer to kind of be adults. The life cycle for the adults is usually July and August.”

Jennifer Babin-Fenske is an entomologist and the coordinator of Earth Care at the City of Greater Sudbury. (Erik White/CBC )

But why is the antennae on the bug so big? Babin-Fenske says that has to do with finding a mate.

“For a lot of males, the antennae are longer,” she said. “For a lot of insects, the antennae for males helps them sense the pheromones of the females.”

Babin-Fenske adds the insects have “huge jaws” to chew through wood.

“They can give a bit of a bite,” she cautioned. “But if you don’t bother them, they won’t bother you.”

Morning North host Markus Schwabe noticed a few large black bugs in his backyard recently. Plenty of social media posts refer to the same bugs. Being the curious person he is, Markus contacted someone who has a special interest in insects. That’s Jennifer Babin-Fenske, the coordinator for Earthcare Sudbury Initiatives. 6:40

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