The ocean is a vast, quiet place, right? Vast, yes; quiet, not so much.
As a researcher who studies coral reefs, I’ve floated above many and, when I listen closely, my ears are invariably filled with sounds. There might be the sound of small waves breaking on the beach and coral rubble rolling on the sand as the waves retreat. Beyond the sound of water, there is something quieter.
For some people, these faint noises sound like the snap, crackle and pop of breakfast cereal when milk hits it; for others, they are reminiscent of frying bacon.
Whatever the analogy, they are natural reef sounds, and noisy reefs are a very good thing. So good, in fact, that we might be able to use the sound of healthy coral reefs to improve the quickly increasing number of degraded ones.
For the past three decades, rising ocean temperatures have put the world’s coral reefs under a great deal of stress. Extreme events can kill large portions of a reef in a short time. For example, 29 per cent of Great Barrier Reef corals died during the the 2016 marine heatwave. It can take 15-25 years for a reef to recover from a bleaching event.
High-frequency sounds tend to be produced by invertebrates. Of these, snapping shrimps are the winners in terms of pitch and loudness. Snapping shrimps have one enlarged claw that, due to a marvel of anatomy and physics, makes an audible snap when closed rapidly.
The modest snapping shrimp. (Shutterstock)
If you had your ear next to the tiny crustacean, the sound could reach 190 decibels, louder than any jet plane taking off. Luckily, no one will ever be that close since these shrimps live deeply ensconced in coral crevices, snapping away day and night.
Why is sound important?
Most coral reef animals spend the early part of their lives as tiny larvae floating in the water. This larval period can last from a few days to several weeks, moving a few metres to hundreds of kilometres from where it was born.
For those long-distance dispersers, the ability to find a new home in the vastness of the ocean is critical. Three decades ago, scientists thought that larval fish were transported at the whim of currents; settling onto a new piece of real estate was largely a matter of chance.
Reef noise can also repel some fish larvae, perhaps because it reveals that there are too many predators or too few potential shoal mates. These species settle in places with sounds they dislike the least, rather than like the most.
The underwater soundscape is critical for a fish larva to know whether there is a coral reef nearby, and whether that reef is a good place to settle. But some species have better hearing than others, and the depth and structure of the habitat can also affect the way sounds emanate from the reef.
Can we use sound to repopulate degraded reefs?
It’s an obvious step to go from knowing that natural sounds are important for fish recruitment to using those same sounds to actively attract fish to depleted reefs.
A recent experiment tested this idea and found it promising. Twice as many fish, across all the major feeding groups, settled on coral-rubble reefs that played the sounds of healthy reefs than on similar but silent reefs. Healthy sounding reefs also attracted 50 per cent more species.
This suggests that acoustic enrichment could be a new and potentially powerful tool to help build up fish communities on unhealthy coral reefs. The authors warned it has to be used alongside interventions to tackle the causes of coral reef decline, climate change in particular.
Without these simultaneous actions, using an attractive soundtrack to invite small fish onto degraded reefs that offer little food or shelter would be false advertisement. And that never ends well for the fooled party.
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
