The Guardian

A police insider has told the Guardian that the killers of Wayne Lotter may have been following him

Police believe Wayne Lotter’s killer may have followed and targeted the conservationist when he was shot on Wednesday, according to inside sources.

Lotter was stopped and then fatally shot while travelling by taxi from Dar es Salaam airport to a hotel. He had been working in Tanzania for many years, exposing and jailing wildlife poachers and traffickers, and he had received a number of death threats. Tanzania’s director for criminal investigation, Robert Boaz, said a murder investigation was underway.

Brown bears fishing, a rare white moose, and a puma found in a São Paulo office block are among our images from the natural world this week

Clouds cool the planet by reflecting solar energy back to space and also trap heat and radiate it back to Earth. In a Yale Environment 360 interview, physicist Kate Marvel discusses the double-edged effect clouds have on rising temperatures

Clouds perform an important function in cooling the planet as they reflect solar energy back into space. Yet clouds also intensify warming by trapping the planet’s heat and radiating it back to Earth. As fossil fuel emissions continue to warm the planet, how will this dual role played by clouds change, and will clouds ultimately exacerbate or moderate global warming?

Kate Marvel, a physicist at Columbia University and a researcher at Nasa’s Goddard Institute for Space Studies, is investigating the mysteries of clouds and climate change. In an interview with Yale Environment 360, she discusses what is known about the behaviour of clouds in a warming world (they are migrating more toward the poles), why strict controls need to be imposed on geoengineering experiments with clouds, and why she is confident that science and human ingenuity will ultimately overcome the challenge of climate change.

Lib Dem leader Vince Cable questions UK’s commitment to environmental projects after GIB sale to Australian bank Macquarie

The government is facing renewed criticism after pushing through the “disastrous” sale of the Green Investment Bank (GIB) to the Australian bank Macquarie, as fresh concerns are raised over its commitment to environmental projects.

A consortium led by Macquarie agreed to buy the GIB, which was established in 2012 by the coalition government to fund green infrastructure projects such as windfarms and a waste and bioenergy power plant. The consortium also includes Macquarie’s in-house infrastructure fund and the Universities Superannuation Scheme, a pension fund for British higher education institutions.

Minninglow, Derbyshire The Y Not festival site is still a mess, but a walk along the High Peak Trail underlines the resilience of nature

At the top of Gratton Dale, turning into Mouldridge Lane, the familiar white-walled pasture had been transformed. Diggers and tractors swarmed across the fields, beeping frantically. Grass had been churned up everywhere, and serried ranks of portable loos leaned like wearied soldiers. I was baffled. Was this some sort of war re-enactment?

Then I saw the word TONY spelled out in giant letters in the middle of the busiest field, only the Y was drooping and the N was the wrong way round.

From elephant shrew to Tibetan antelope and the two towers of Antarctica, here are the best wildlife and nature photographs from this year’s competition

State mines minister rejects two applications at reserves west of Cape Tribulation which campaigners say should set a precedent

The “archaic” practice of mining rivers in north Queensland is making a mockery of Australia’s key policy to protect the Great Barrier Reef, wasting multimillion-dollar efforts to cut runoff pollution, its opponents say.

“Instream” mining in Queensland, the only state still allowing the excavation of rivers for gold, tin and silver, is unleashing torrents of fine sediment in one of the reef’s largest catchments.

Wayne Lotter had received numerous death threats while battling international ivory-trafficking networks

The head of an animal conservation NGO who had received numerous death threats has been shot and killed by an unknown gunman in Tanzania.

Wayne Lotter, 51, was shot on Wednesday evening in the Masaki district of the city of Dar es Salaam. The wildlife conservationist was being driven from the airport to his hotel when his taxi was stopped by another vehicle. Two men, one armed with a gun opened his car door and shot him.

Elusive and endangered white-letter hairstreak discovered in a field in the Scottish borders could become the 34th species to live and breed in the country

Scotland has a new species of butterfly: the elusive and endangered white-letter hairstreak has been discovered in a field in Berwickshire, 100 metres from the English border.

Qualified graduates are struggling to find paid jobs and many give up to pursue a different career. The result is a net loss for conservation work, reports Mongabay

Nika Levikov swore she would never work as a waitress again. But, today — with a master’s degree in conservation science from Imperial College London — she’s taking orders, delivering drinks, and cleaning tables to support herself.

Supermarkets selling out-of-date produce and apps that identify food at risk of being binned are part of an ambitious plan to slash the nation’s food waste

“They might not taste quite the same,” says Naeeh Ahmed, 37, holding up for inspection a pack of Old El Paso soft tacos. The tower of boxes in front of him are three weeks past their best before date but Ahmed, operations manager at the Best Før supermarket in Oslo, says they’ll stay on display for a good few weeks yet. The same goes for the chocolate biscuits precariously piled up in the display – four weeks past their best before date – and the packs of Tassimo coffee pods that should have been sold in April. But all the prices reflect the product’s age: half-price for the tacos, two-thirds off the biscuits and, at 30 kroner (£3.66) for 32 pods, the coffee is also less than half its regular price.

It would be hard to find cheaper food in Oslo than that sold at Best Før. They flog the stuff that no one else has been able to get rid off. Products whose season has passed, or which have been overproduced, have been arriving at this small store since October last year when the mainstream Lentusgruppen supermarket chain heeded the call of the Norwegian government and decided to take food waste seriously. They established an offshoot in Oslo, the first of its kind in the city, selling the stuff other stores and suppliers throw away. It’s all up front – the shop looks like any other, but a large sign informs customers of the slightly different nature of the food down their aisles and in the chillers, which includes chicken fillets frozen a couple of days before going off.

The Ride of the Falling Rain on the Hebridean island of Islay has no entry fee, route card or medals, but its laidback, friendly vibe keeps riders coming back despite the weather

The Ride of the Falling Rain is an annual cycling event on the Hebridean island of Islay that proudly describes itself as “anti-sportive”.

Held on the first Sunday in August, there is no entry fee, no feed stations, no timing chips and no medal or certificate at the end. Yet in its 14-year history, it has attracted a hard core of regulars who travel from all over the UK.

Prof John Underhill argues that geology is fundamental but has been forgotten in assessments of UK’s shale gas capability

Fracking for oil and gas in the UK may produce much less fuel – and profits – than has been mooted, according to research based on seismic imaging of the country’s underlying geology.

Most of the areas in which deposits of onshore “unconventional” gas and oil are likely to be found were affected by tectonic activity along the Atlantic plate about 55m years ago.

Daddry Shield, Weardale The architecture of the flower choreographs the insects’ movements, making pollination likely

The footpath to St John’s Chapel, through hay meadows long since cut, follows the south bank of the Wear. Today the water was shallow and clear. But after heavy rain in the upper dale the river becomes a torrent and it has eroded small terraces so stony and steep they are never cut at hay time. These places are refuges for a late-summer flora of Campanula rotundifolia, harebells as blue as the sky overhead.

It’s a place to sit among the flowers on an afternoon when summer seems to be slipping past too quickly.

The sudden collapse of a 200-year-old oak in Madeira, killing 13 and injuring many others (Report, 16 August), is a salutary warning to the tree protesters of Sheffield (Report, 16 August). Local authorities and other custodians of parklands and highways have a duty to ensure that trees do not endanger the public when they deteriorate through age or disease. Inspecting trees is a specialist task best carried out by trained professionals. Doubtless Sheffield city council has been doing just that. If a tree collapsed on the protesters or damaged their properties they would be protesting against the council, and more likely suing them, for failing to safeguard them. The hapless council is damned if it does and damned if it doesn’t take action.
Paul Faupel
Somersham, Cambridgeshire

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Three wildlife rangers at DRC’s Virunga national park were killed this week in an ambush by Mai Mai rebels, bringing this year’s fatalities to eight

Three rangers have been killed and another is missing after an attack by violent militia in Virunga national park in the Democratic Republic of the Congo, bringing the number of fatalities in the park this year to eight.

The park rangers, Charles Paluku Syaira, Jonas Paluku Malyani and Pacifique Musubao Fikirini were murdered on the morning of Monday 14 August during a routine patrol around the park, which is home to critically endangered mountain gorilla.

Exclusive: Nearly 12m barbecues in the UK likely to over-cater with food ranging from salads to burger rolls ending up in bins

It’s symbolised by dismal burgers and carbonised sausages served on paper plates with a splatter of ketchup. Yet with the great British summer well under way, Britons are this month set to throw away a staggering £428m worth of barbecue food, research reveals.

In August the nation will brave the changeable weather to enjoy nearly 12m barbecues, with people on average either hosting or attending at least two of the seasonal gatherings. The new research from supermarket chain Sainsbury’s shows that hosts typically over-cater to impress friends and family, with more than half (49.2%) putting on a larger than necessary spread.

Behavioural evidence suggests marine organisms are not just ingesting microplastics by accident but actively seeking them out as food

Fish may be actively seeking out plastic debris in the oceans as the tiny pieces appear to smell similar to their natural prey, new research suggests.

The fish confuse plastic for an edible substance because microplastics in the oceans pick up a covering of biological material, such as algae, that mimics the smell of food, according to the study published on Wednesday in the journal Proceedings of the Royal Society B.

Kennards House, Cornwall At the agricultural show white-coated exhibitors vie for prizes as the heavy horses are hitched and cocks crow in the poultry tent

After noting the whereabouts of their parked cars relative to the windblown hedgerow trees, visitors converge on the entrance to Launceston’s one-day agricultural show.

Cloud shrouds Kit Hill to the south but Caradon, Kilmar Tor and Hawk’s Tor on Bodmin Moor, as well as nearby wind turbines, are silhouetted against an increasing expanse of blue sky.

Sierra Leonean emergency services and aid agencies are working to find victims of the heavy mudslides and flooding which devastated areas around the country’s capital Freetown on Monday. Thousands of people are still missing

• Sierra Leone’s deadly mudslide: thousands missing as search continues