Study Documents Extinction of 610 Bird Species, Ecological Impacts

A flock of Common Teal fly across a wetland on a winter day on the outskirts of Srinagar January 22, 2018. REUTERS/Danish Ismail/File Photo
A flock of Common Teal fly across a wetland on a winter day on the outskirts of Srinagar January 22, 2018. REUTERS/Danish Ismail/File Photo
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Study Documents Extinction of 610 Bird Species, Ecological Impacts

A flock of Common Teal fly across a wetland on a winter day on the outskirts of Srinagar January 22, 2018. REUTERS/Danish Ismail/File Photo
A flock of Common Teal fly across a wetland on a winter day on the outskirts of Srinagar January 22, 2018. REUTERS/Danish Ismail/File Photo

The Dodo, the famous flightless bird that inhabited the Indian Ocean island of Mauritius, is a case study in extinction caused by humans. The Dodo, finely adapted to its isolated ecosystem but unprepared for the arrival of people, was first encountered by Dutch sailors in 1598. Hunting, habitat destruction and the introduction of non-native species doomed it in under 80 years.

It is hardly alone. New research has documented the extinction of 610 bird species over the past 130,000 years, coinciding with the global spread of our species Homo sapiens, an avian crisis that has only accelerated in recent years and decades. For instance, the Kauaʻi ʻōʻō, a Hawaiian songbird, was declared extinct just last year.

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The researchers also revealed the ecological consequences, as the disappearance of avian species erases functions they serve in innumerable ecosystems, Reuters reported.

"Birds undertake a number of really important ecosystem functions, many of which we depend on, such as the dispersal of seeds, the consumption of insects, the recycling of dead material - for example, vultures - and pollination. If we lose species, then we lose these functions," said ecologist Tom Matthews of the University of Birmingham in England, lead author of the study published this week in the journal Science, opens new tab.

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"A good example of this is on the islands of Mauritius and Hawaii, where all or almost all the native frugivores - birds that eat fruit - have gone extinct," Matthews said.

The Dodo and Kauaʻi ʻōʻō, believed to have had fruit as part of their diets, were among those.

"Frugivory is an important function, as in eating the fruits and then moving around, birds will disperse the seeds of the plants the fruits belong to," Matthews said.

This can precipitate "secondary knock-on extinctions," Matthews said, with Mauritius now having many threatened tree species.

Most of the documented extinctions occurred on islands. Habitat loss can have huge effects given the isolation and reduced area involved, while the introduction of animals such as rats, cats and mice can have substantial impacts given the evolution of flightlessness among many island-endemic birds that left them unable to escape new predators, Matthews said.

Human hunting was a big extinction driver in the past and remains problematic in certain regions. Capturing birds for the songbird trade is a big issue, particularly in Southeast Asia, Matthews said.

Certain regions and species had more specific factors involved. For example, avian malaria, introduced by people, has triggered large numbers of extinctions in Hawaii - particularly among the endemic Hawaiian honeycreepers - where the birds possessed no natural immunity.

"The big unknown going forward is the role of anthropogenic climate change as a driver," Matthews said.

Some wondrous birds have been lost.

The large flightless elephant birds endemic to Madagascar vanished after people arrived, including Aepyornis maximus, possibly the largest bird that ever existed, about 10 feet (3 meters) tall. The flightless moa birds endemic to New Zealand, including the South Island giant moa that rivaled the elephant birds in size, similarly disappeared after humans colonized the islands.

North America's migratory passenger pigeon numbered in the billions, but was hunted into oblivion.

The 610 species combined represented 3 billion years of unique evolutionary history, the researchers said, with each lost species like chopping off a branch from the tree of life.

The number 610 is "likely a large underestimate" of avian extinctions, Matthews said, because of a paucity of data from some locales and the fact some lost species may not have left behind skeletal remains to be found. Regardless of the true number, Matthews said, "the vast majority of extinctions over the last 50,000 years are attributable to human actions."

About 11,000 bird species now exist, occupying a dizzying array of ecological niches. The researchers projected future extinctions of more than 1,000 species over the next two centuries.

"So even if you don't care about the moral and ethical concerns regarding the loss of species, these extinctions are important for other reasons, such as the loss of species that helped the environment to function effectively," Matthews added.

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Smog Sickness: India’s Capital Struggles as Pollution Surges

An Indian man rides a bike to commute amid heavy smog near New Delhi, India, 05 November 2024. (EPA)
An Indian man rides a bike to commute amid heavy smog near New Delhi, India, 05 November 2024. (EPA)
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Smog Sickness: India’s Capital Struggles as Pollution Surges

An Indian man rides a bike to commute amid heavy smog near New Delhi, India, 05 November 2024. (EPA)
An Indian man rides a bike to commute amid heavy smog near New Delhi, India, 05 November 2024. (EPA)

The toxic smog season in India's capital has just begun, but those unable to escape cancer-causing poisonous fumes say the hazardous impact on health is already taking its toll.

New Delhi regularly ranks among the world's most polluted capitals, with a melange of factory and vehicle emissions exacerbated by agricultural fires blanketing the city each winter, stretching from mid-October until at least January.

Cooler temperatures and slow-moving winds trap deadly pollutants, suffocating the megacity of 30 million people in putrid fumes.

Factory worker Balram Kumar returns home exhausted from work, but then is up all night coughing.

"I am barely able to sleep all night," Kumar, 24, told AFP as he waited outside a special pollution clinic, set up at the government-run Ram Manohar Lohia hospital.

"My chest hurts every time I cough. I have been taking medicines but there is no relief," said Kumar.

He pointed dejectedly to an X-ray of his chest.

"My cough is just not going," he said.

- Thousands of deaths -

On Tuesday, the level of PM2.5 particles -- the smallest and most harmful, which can enter the bloodstream -- topped 278 micrograms per cubic meter, according to monitoring firm IQAir.

That is 18 times the daily maximum recommended by the World Health Organization.

On the worst days, levels can shoot up as high as 30 times the daily maximum.

Piecemeal government efforts to mitigate the smog, such as a public campaign encouraging drivers to turn off their engines at traffic lights, have failed to make an impact.

A study in the Lancet medical journal attributed 1.67 million premature deaths to air pollution in the world's most populous country in 2019.

Air pollution in Delhi has worsened after a fireworks ban was widely flouted for raucous celebrations last week for the Hindu festival of lights, Diwali.

The cracker frenzy turned Delhi's winter skies dull grey.

Doctor Amit Suri, who heads the pollution clinic, said there is usually a surge of 20-25 percent in the number of patients turning up with respiratory issues after the festival.

This year, it is the same story.

"Most of the patients are coming with complaints of dry cough, throat irritation, running of eyes and some of them are also having skin rashes," Suri told AFP.

The hospital provides treatment and medicine free of cost.

None of its patients can afford private healthcare, and many cannot buy an air purifier for their homes.

The WHO says that air pollution can trigger strokes, heart disease, lung cancer and other respiratory diseases.

- 'How will I survive?' -

A study published in the Lancet Planetary Health journal in July said more than seven percent of all deaths in 10 of India's biggest cities were linked to air pollution.

Delhi was the worst offender, with 12,000 annual deaths linked to air pollution -- or 11.5 percent of the total.

India's Supreme Court last month ruled that clean air was a fundamental human right, ordering both the central government and state-level authorities to take action.

But critics say arguments between rival politicians heading neighboring states -- as well as between central and state-level authorities -- have compounded the problem.

"We need to create awareness," said Doctor Ajay Shukla, the hospital's medical superintendent. "The problem is getting bigger by the day."

On the worst days, Shukla said, it is like chain-smoking cigarettes.

Doctors have been counselling the patients and providing a list of what to do to alleviate the health issues.

The main advice is to try and stay indoors, shut doors and windows, and wear anti-pollution masks while outside.

But Kanshi Ram, a 65-year-old daily wage laborer visiting the clinic, said he did not know what he should do to ease his nagging cough, which has kept him off work this week.

"Doctors are asking me not to go out and breathe the polluted air," Ram, who earns 500 rupees ($6) for each day that he works.

"But how will I survive if I don't go out?" he added. "I feel so helpless."