Speedy Animal Control, San Diego CA

Specieswatch: Wild deer release millions of tonnes of methane a year

Scientists find ruminants emit more of greenhouse gas individually than cows, although total contribution tiny compared with domesticated livestock

When cows belch and fart they release methane, which is warming the planet, but how does this compare with the digestive gases emitted by wild animals? A new study shows that deer add the greatest amount of methane to the atmosphere, but compared with domesticated livestock their total contribution is minuscule.

Methane is a potent greenhouse gas, which has been rising rapidly in recent years, but it is hard to pin down exactly where it is coming from. Like domesticated cows, wild ruminants such as deer, moose and llamas rely on bacteria to help them break down the fibrous plants they eat, releasing methane as they go. To understand how much methane wild ruminants release, Theresia Yazbeck, from the Max Planck Institute for Biogeochemistry in Jena, Germany, and colleagues used recent estimates of global wild animal populations and combined these with methane emission estimates based on body mass and diet.

Invertebrate of Year Q&A: discuss our countdown with Patrick Barkham

This week, we launched our third annual vote to honour nature’s unsung heroes. The Guardian’s natural history writer – and woodlouse fanboy – Patrick Barkham will be here from 4pm BST (11am EDT) to discuss this year’s poll and why we must celebrate the spineless

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What do the tardigrade and the earthworm have in common? They are, of course, the two previous winners of the Guardian’s Invertebrate of the Year poll. An annual contest that pits some of the the natural world’s finest species against each other in celebration – and to remind ourselves why beetles, slugs, worms and moths and others play a critical role in the planet’s infrastructure.

Contenders to take the tardigrade’s crown this year include the common woodlouse and the immortal jellyfish. We’ll be revealing the rest of the shortlist over the next few days.

As the Guardian’s natural history writer, Patrick is one of the UK’s foremost nature writers and has written books about badgers, moths and his lifelong love of the outdoor world. His recent reporting has looked at rewilding projects, the homing habits of swifts and people pretending to be otters.

Calls to ban ‘toxic’ pet flea treatments that harm UK wildlife and environment

Over-the-counter treatments for cats and dogs contain chemicals that are banned in pesticides and pollute waterways

Over-the-counter flea treatment for cats and dogs should be banned as millions of hazardous chemicals are unnecessarily applied to UK pets each year, a parliamentary report has concluded.

Cats and dogs are widely treated with topical, or “spot on”, treatments that include insecticides to prevent fleas. Vets often recommend regular treatments as a preventive measure, even when the animals do not have fleas.

It’s Invertebrate of the Year again! Every day from 3-12 August, we will be profiling one of the thousands of amazing invertebrates that our readers have nominated, and when you have heard about all of them, we will open the voting so you can choose your favourites. Don’t hesitate to get in touch with thoughts and ideas. Email us at environment.desk@theguardian.com with Invertebrate in the subject line.

Country diary: A beetle with a prehensile anus? Thanks to local wildlife recorders, I know one lives here | Gwyneth Lewis

Troedyraur, Ceredigion: Let’s sing the praises of this network of volunteers who move slowly and look hard, gathering vital wildlife data – and finding fantastic species

Even before we start a Wildwatch recording morning, Carys May of the West Wales Biodiversity Information Centre has made two identifications: an intimidating dark giant horsefly (Tabanus sudeticus) with huge eyes close together and a notch-horned cleg or horsefly (Haematopota pluvialis), which bit me.

As we walk through Pencoedtop, a former conifer plantation now being restored to moorland (rhos in Welsh), Carys moves slowly and looks hard. She spots a mining bee, one that can only be identified under a microscope. This one doesn’t collect pollen neatly in its leg baskets, but exits flowers covered in powder, which the female seals into her nest with her eggs. In a bank of brambles, Carys points out several marmalade hoverflies (Episyrphus balteatus), which look like slim wasps. These pollinators migrate at great heights from the continent. She says that, if in doubt, the county hoverfly recorder, like a kind of naturalist archangel, is quick to respond to queries.

Penguins and dolphins among nearly 400 Australian species under threat from bird flu as ‘true extent of disaster’ revealed

Assessment of more than 2,000 native species warns nearly one in five at high risk of deadly H5N1, including parrots, fur seals and quolls

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Almost 400 native Australian bird and mammal species have been assessed as being at a high risk – or worse – from the deadly H5N1 bird flu virus, a federal government assessment has revealed.

Some of Australia’s most beloved animals – including species of penguins, fur seals, quolls, dolphins, more than 300 birds and the Tasmanian devil – are considered at least high risk from the virus, meaning they could suffer “severe reduction in population size or viability” or worse if it reached them.

Campaign warns of perils UK waters can pose for dogs and owners

Dogs Trust points to hundreds of incidents over recent years, some involving deaths of pets or people

With its gentle rippling water, tall purple flowers and rustling trees, Earlswood Lakes near Solihull in the West Midlands seems the perfect spot for dogs to paddle. But their owners have been warned that the otherwise idyllic open water could prove perilous to pets.

“We’ve had all this hot weather and millions of families are now spending time around open bodies of water, and it’s easy to not realise the dangers,” said Emma-Jane Thomas, rehoming manager at Dogs Trust Kenilworth during a walk around Earlswood.