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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.

Redflow says first ZCell residential battery storage systems to be delivered to customers next month after first shipment of batteries arrived in Australia on Sunday.

Continued technological advancements are expected to continue reducing the cost of wind energy, according to a new survey of leading wind experts.

Tesla wins contract to install 20MW/80MWh Powerpack for Southern California Edison Mira Loma Substation.

What happens when a climate science denialist gets things badly, horribly, terribly, and embarrassingly wrong.

University of Queensland to add 200kW RedFlow zinc bromine battery to its world-leading solar research facility to test how it helps renewables interact with the grid.

Originally published in the Manchester Guardian on 25 September 1916

The serpentine stones which form the shingle on the Lizard peninsula are very tempting to collect, and we have had the happy idea of using them in bowls this winter, to grow narcissi in and Roman hyacinths. A child is the pure artist in collection. He needs no apology. The mere contemplating of his hoards, laying them out in array, counting and sorting, is amply enough joy for him. But we grown-ups are compelled to seek a plea of use, and, having found it, we may indulge our childishness. It is fortunate that the use we have hit upon allows, since we cannot learn to polish the stones, of the next best way of bringing out the colours – by wetting them.

They are very varied, these pebbles; veined or mottled, or netted, or broadly banded; colours laid one over the other or side by side. The greys sometimes get very near blue, mostly lilac or indigo blue. The greens are mostly yellowish or mossy, but there is a very handsome laurel green, not often found. The reds are mostly a rich and deep Indian red, but there are found occasional delicate pink shades. I have in my hand one pebble made up of broad bands of Indian red alternating with iron grey, a sombre combination; another dark one has a background of lavender with a fine network of the same red; more beautiful is the same lavender veined with purple.

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