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Outdoor exercise delivers an estimated £2.2bn of health benefits to adults in England each year, a study suggests.

China has been building two wind turbines every hour, the International Energy Agency (IEA) has told BBC News.

Invasive species are a threat to wildlife across the globe – and invasive, predatory mammals are particularly damaging.

Our research, recently published in Proceedings of the National Academy of Sciences, shows that these predators – cats, rats and foxes, but also house mice, possums and many others – have contributed to around 60% of bird, mammal and reptile extinctions. The worst offenders are feral cats, contributing to over 60 extinctions.

So how can we stop these mammals eating away at our threatened wildlife?

Counting the cost

Our study revealed that invasive predators are implicated in 87 bird, 45 mammal and 10 reptile extinctions — 58% of these groups’ contemporary extinctions worldwide.

Invasive predators also threaten 596 species classed as vulnerable, endangered or critically endangered on the International Union for the Conservation of Nature Red List. Combined, the affected species include 400 birds, 189 mammals and 149 reptiles.

Twenty-three of the critically endangered species are classed as “possibly extinct”, so the number of extinctions above is likely to be an underestimate.

Until now, these shocking statistics have been unknown, and the heavy toll of invasive predators on native biodiversity grossly underappreciated. Species extinctions attributed to invasive predators include the Hawaiian rail (Zapornia sandwichensis) and Australia’s lesser bilby (Macrotis leucura).

Australia’s lesser bilby, now extinct. Who are the worst offenders?

We found that three canids (including the red fox and feral dogs), seven members of the weasel family or mustelids (such as stoats), five rodents, two primates, two mongooses, two marsupials and nine species from other families negatively impact threatened species. Some of these species, such as hedgehogs and brushtail possums, don’t immediately spring to mind as predators, yet they are known to prey on many threatened species.

Feral cats threaten the most species overall (430), including 63 that have become extinct. This equates to one-quarter of all bird, mammal and reptile extinctions – making the feral cat arguably the most damaging invasive species for animal biodiversity worldwide.

Five species of introduced rodent collectively threaten 420 species, including 75 extinctions. While we didn’t separate out the impacts of individual rodent species, previous work shows that black rats (Rattus rattus) threaten the greatest number of species, followed by brown rats (R. norvegicus) and Pacific rats (R. exulans).

The humble house mouse (Mus musculus) is another interesting case. Despite their small size, house mice have been recorded eating live chicks of albatrosses, petrels and shearwaters.

Other predators that threaten large numbers of species are the domestic dog (Canis familiaris), pig (Sus scrofa), small Indian mongoose (Herpestes auropunctatus), red fox (Vulpes vulpes) and stoat (Mustela erminea).

Invasive mammalian predators (clockwise from top left): feral dog, house mouse, stoat, feral pig, feral cat, brushtail possum, black rat, small Indian mongoose and red fox (centre). Clockwise from top-left: Andrey flickr CC BY 2.0 https://flic.kr/p/4M2E7y; Richard Adams flickr CC BY 2.0 https://flic.kr/p/7U19v9; Mark Kilner flickr CC BY-NC-SA 2.0 https://flic.kr/p/4D6LPe; CSIRO CC BY 3.0 http://www.scienceimage.csiro.au/image/1515; T. Doherty; Toby Hudson CC BY-SA 3.0 https://commons.wikimedia.org/wiki/File:BrushtailPossum.jpg; CSIRO CC BY 3.0 http://www.scienceimage.csiro.au/image/10564; J.M.Garg CC BY-SA 3.0 https://commons.wikimedia.org/wiki/File:Herpestes_edwardsii_at_Hyderaba.jpg; Harley Kingston CC BY 2.0 https://flic.kr/p/ceWFr7 (centre). Island species most at risk

Species found only on islands (insular endemics) account for 81% of the threatened species at risk from predators.

The isolation of many islands and a lack of natural predators mean that insular species are often naive about new predators and lack appropriate defensive responses. This makes them highly vulnerable to being eaten and in turn suffering rapid population decline or, worse, extinction. The high extinction rates of ground-dwelling birds in Hawaii and New Zealand — both of which lack native mammalian predators — are well-known examples.

Accordingly, the regions where the predators threatened the greatest number of species were all dominated by islands – Central America and the Caribbean, islands of the Pacific, the Madagascar region, New Zealand and Hawaii.

Conversely, the continental regions of North and South America, Europe, Africa and Asia contain comparatively few species threatened by invasive predators. While Australia is a continent, it is also an island, where large numbers of native birds and mammals are threatened by cats and foxes.

Along with feral cats, red foxes have devastated native mammals in Australia. Tom Rayner Managing menacing mammals

Understanding and mitigating the impact of invasive mammal predators is essential for reducing the rate of global biodiversity loss.

Because most of the threatened species studied here live on islands, managing invasive predators on islands should be a global conservation priority. Invasive predators occur on hundreds of islands and predator control and eradication are costly exercises. Thus, it is important to prioritise island eradications based on feasibility, cost, likelihood of success and potential benefits.

On continents or large islands where eradications are difficult, other approaches are needed. This includes predator-proof fencing, top-predator restoration and conservation, lethal control, and maintenance of habitat structure.

Despite the shocking statistics we have revealed, there remain many unknowns. For example, only around 40% of reptile species have been assessed for the Red List, compared to 99% for birds and mammals. Very little is known about the impact of invasive predators on invertebrate species.

We expect that the number of species affected by invasive predators will climb as more knowledge becomes available.

This article was co-authored by Al Glen from Landcare Research, New Zealand.

Tim Doherty has received funding from Earthwatch Institute Australia, Gunduwa Regional Conservation Association, Holsworth Wildlife Research Endowment, Edith Cowan University and Deakin University. Tim is affiliated with the Society for Conservation Biology (Oceania).

Chris Dickman receives funding from the Australian Research Council, the Long Term Ecological Research Network and the Threatened Species Recovery Hub of the National Environmental Science Programme.

Dale Nimmo receives funding from the Hermon Slade Foundation, the Department of Land, Water and Planning, the Department of Parks and Wildlife, Parks Victoria, and The Australian Academy of Science. He is affiliated with the Ecological Society of Australia.

Euan Ritchie receives funding from Pozible, the Australia and Pacific Science and Hermon Slade Foundations, and the Australian Research Council. Euan Ritchie is affiliated with the Ecological Society of Australia and the Australian Mammal Society.

An era of so-called reconciliation has disguised the continuation of Harper-era land and resource grabs

By now, we all know the greatest priority of Justin Trudeau’s Liberal government is its relationship with Indigenous peoples. How could we miss the weekly reminders?

Trudeau graciously wrapping himself in ceremonial blankets. Hauling jugs of drinking water door-to-door on a northern reserve lacking portable water. Paddling the Ottawa river in his dad’s buckskin jacket and moccasins with Indigenous youth, after a sunrise ritual at dawn.

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Talk of prohibiting, preventing and countering corruption must take centre stage when signatories to the Cites treaty on regulating the international trade in wildlife meet in Johannesburg this weekend

The world is witnessing an unprecedented surge in wildlife trafficking that is stealing the irreplaceable natural wealth of countries, greatly hindering development, paralysing efforts to eradicate poverty, and undermining conservation efforts. This illicit trade in wildlife is well organised, transnational and happening across every region.

As countries prepare to meet in Johannesburgthis weekend for the 17th meeting of the Conference of the Parties to Cites (CoP17), there is increasing recognition that to curb the global surge in wildlife trafficking we must counter the corrosive corruption that enables it.

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The original Bramley apple tree and the inspiration for the mulberry bush nursery rhyme are among the 29 trees in England, Scotland, Wales and Northern Ireland that have been shortlisted by the Woodland Trust for its annual tree of the year competition.

Experts whittled down nearly 200 public nominations based on the tree’s story, how they would use the £1,000 care grant and visual appeal of the tree. Members of the public can vote for their favourite tree by country before 10 October with the winners going forward to the European tree of the year competition in early 2017.

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A quiet crisis playing out in US forests as huge numbers of trees succumb to drought, disease, insects and wildfire – much of it driven by climate change

JB Friday hacked at a rain-sodden tree with a small axe, splitting open a part of the trunk. The wood was riven with dark stripes, signs of a mysterious disease that has ravaged the US’s only rainforests – and just one of the plagues that are devastating American forests across the west.

Friday, a forest ecologist at the University of Hawaii, started getting calls from concerned landowners in Puna, which is on the eastern tip of Hawaii’s big island, in 2010. Their seemingly ubiquitous ohi’a trees were dying at an astonishing rate. The leaves would turn yellow, then brown, over just a few weeks – a startling change for an evergreen tree.

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Sacha Dench will follow Bewick’s swans on their annual journey from the Russian Arctic in a motorised paraglider in a bid to shed light on their decline

A British conservationist took to the skies in a motorised paraglider on Monday morning for the start of a daring 4,500-mile expedition across the Russian Arctic that will attempt to shed light on the decline of the UK’s smallest, shyest species of swan.

For the next 10 weeks, Sacha Dench, 41, will act as a “human swan” and follow the route of thousands of Bewick’s swans on their annual migration. From the tundra of Siberia she will head west and south through 11 countries including Finland, Poland and Germany to the swans’ wintering grounds in Britain and other parts of western Europe.

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A 16-year study found that we’re at a point where more CO2 won’t keep increasing plant production, but higher temperatures will decrease it

A new study by scientists at Stanford University, published in the Proceedings of the National Academy of Sciences, tested whether hotter temperatures and higher carbon dioxide levels that we’ll see post-2050 will benefit the kinds of plants that live in California grasslands. They found that carbon dioxide at higher levels than today (400 ppm) did not significantly change plant growth, while higher temperatures had a negative effect.

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Scientists will sail from the UK to the Falkland Islands to study scale of microplastic pollution on tiny zooplankton at the bottom of the food chain

Scientists will set off from the east coast of England this week to journey thousands of miles across the Atlantic to discover how bad the problem of the oceans’ tiniest creatures eating microplastics has become.

Zooplankton are essential for the marine food web right up to the fish we eat, and are known to be more likely to die and be worse at reproduction after eating the minuscule pieces of plastic.

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Government was seeking at least $120m, while Shenzhen Energy Transport Co Ltd argued reef was self-healing

The federal government has reached a $39.3m out-of-court settlement with the owners of a Chinese coal carrier that ran aground on the Great Barrier Reef in 2010.

Shenzhen Energy Transport Co Ltd and its insurer had, for six years, refused to accept responsibility for restitution after the 225m long, fully laden Shen Neng 1 ran aground 100km east of Rockhampton at Douglas Shoal.

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Allowing mangrove forests to recover naturally result in more resilient habitats that benefit both wildlife and people, say conservationists.

Tarn Hows, Lake District One of the most popular destinations in the north-west, the tarn is made more accessible by free four-wheeled Tramper buggies available from the National Trust

Bunches of crimson berries hang heavy from the rowan trees, like knuckledusters punching colour along Tarn Hows’s famously photogenic shores. I remark on this to a couple piloting battery-powered mobility scooters past the bench where I’m seated. Why haven’t birds snaffled them? “Not quite ripe enough maybe,” ventures the woman. “But flocks of fieldfares will soon arrive from Scandinavia and scoff them up.” On cue several fieldfare look-a-likes – mistle thrushes with black-speckled mustard-coloured breasts – swoop by, though they ignore the berries.

The scooter drivers disappear along the crushed stone path that guides walkers and cyclists for more than a mile and a half round the tarn. Created from three smaller tarns and landscaped in the 19th century by the industrialist James Garth Marshall, it was later sold to Beatrix Potter, who bequeathed the site with its expanding plantations of spruce, larch and pine in 1930 to the National Trust.

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Eucalyptus oils from certain gum tree species could be refined to make high energy jet fuel, an ANU study has found.

The average margin for a rooftop solar installation in the United States market is 40 per cent. In Australia, some installers are struggle to get into double figures. Consumers aren't complaining though.

South Australia electricity price falls; Infigen Energy gives up 30%; why biggest gas pipeline operator is no saint; and the big questions over Victoria renewable energy target.

Event Reminder - Our Climate & Energy Dilemma

Scientists are hoping to stop cane toad migration across Australia by creating a dry zone south of Broome.

Sun Brilliance wants its solar plant to become a visitor complex for weddings, parties ... and a nice cuppa tea. Now, why didn't coal fired power stations think of that?

The second-noisiest animal in the ocean, the snapping shrimp. Dr Tullio Rossi, CC BY-SA

Despite appearances, the oceans are far from silent places. If you dunk your head underwater you’ll hear a cacophony of sounds from wildlife great and small, crashing waves, and even rain. And it’s louder still for creatures attuned to these sounds.

However, humans are changing these ocean soundscapes. Our recent research showed that changes caused by people, from ocean acidification to pollution, are silencing the seas' natural noises. (We’re also filling the oceans with human noise).

This is bad news for the species that depend on these noises to find their way.

Ocean soundscapes

All over the world you can hear a lively crackling sound made by thousands of snapping shrimp that live along coastlines.

These common shrimp, often referred to as pistol shrimp, have a large claw that they can close with such force that a cavitation bubble is formed. As this bubble implodes on itself a loud snap is created – like a pistol shot – which can be heard over long distances.

In fact, snapping shrimp are the loudest marine invertebrates, and second only to the noisest marine animals, which are sperm whales! Snapping shrimp are found all over the world, including in coral reefs, kelp forests, seagrass beds and mangroves.

Other types of animals create ocean noise too. Urchins and parrotfish make clearly audible chomping sounds as they scrape algae off rocks. Many fish are frequent and loud talkers and make an array of sounds such as chirps, burps, whistles, knocks and so on. They use these to mark out their territory, during fights and to locate mates.

These biological sounds, together with those from rain, crashing waves and seismic activities, form the so-called underwater soundscape.

Learn more about marine soundscapes watching this video.

Sounds that are emitted from temperate and tropical reefs are loud and quite constant. As such these sounds form a reliable source of information for animals, particularly for navigation.

Most animals in the sea let go of their fertilised eggs without providing any parental care. As these eggs hatch, small babies (larvae) are dispersed by ocean currents. Growing up away from coastal areas provides a safer place with fewer predators.

However, after growing for a few weeks or months in the open ocean, it is time for these young animals to return to the coast to find a home. How do they find their way in the vast and uniform open ocean? Sounds and odours from coastal habitats are key cues that allow marine animals to find their new homes and replenish adult populations.

Going quiet

Humans are increasingly dominating the physical and chemical environment. We are altering the carbon cycle through the burning of fossil fuels and the nitrogen cycle by extracting vast amounts of nitrogen for food production and releasing it as waste. Large amounts of this carbon and nitrogen liberation end up in the ocean.

About one-third of the carbon dioxide that humans emit into the atmosphere dissolves in the ocean, leading to increased seawater acidity (or ocean acidification). This is an obvious problem for animals that produce a calcium carbonate shell or skeleton (such as corals, some plankton, and snails). Remarkably, ocean acidification also alters the behaviour of many animals by messing up their brain functioning.

Earlier studies (see also here) have shown that ocean acidification can change the response of fish larvae to settlement habitat sounds by deterring them rather than attracting them.

Learn more about the effects of ocean acidification on fish behaviour watching this animation video.

Two of our recent studies (see also here) showed that ocean acidification not only affects sound reception, but also the sounds that ocean ecosystems produce. If we don’t reduce greenhouse gas emissions, rocky reefs could be much quieter in 2100 than now. And snapping shrimps are the reason.

Coastal discharge of nutrients from sewage plants and catchment runoff also degrades kelp forests and seagrass beds. These coasts are more silent than their healthy counterparts.

In many parts of the world, kelp forests, seagrass beds and coral reefs have been replaced by carpets of turf-forming or mat-forming algae. These weedy types of algae have much lower diversity of species and provide less shelter and feeding opportunities for shrimps and other noisy animals.

Degraded habitat means fewer animals, which means less noise. For larvae that use sound as a navigational cue, this means that fewer larvae will be able to successfully locate their home. And fewer returning larvae means less replenishment of fish stocks.

The effects of ocean acidification on fish orientation and soundscapes. Dr Tullio Rossi Options for restoration

Climate change and ocean acidification act at global scales and are difficult to stop in the short term. In contrast, nutrient pollution is a local stressor, which makes it more manageable.

Various options exist for local communities to reduce nutrient pollution of coastal areas. These include improved sewage treatment, restoration of coastal vegetation (such as mangroves) and swamps that extract sediment and nutrients from stormwater runoff, and decreasing the use of rivers as outlets for polluted waters.

Reducing the impacts of nutrient pollution on coastal ecosystems makes these systems more robust and provides them with increased resilience to cope with the impacts of ocean warming and acidification.

Ivan Nagelkerken receives funding from The Australian Research Council.

Sean Connell receives funding from The Australian Research Council.

Tullio Rossi owns the YouTube channel where the linked videos are hosted.