A single fink. I stop for the call’s repeat. Instead, the confirmation that a chaffinch has joined the dawn chorus comes with a brief trill culminating in a wheezy flourish. The song is a little like the bird itself: a common thing that’s riven with significance. For the chaffinch is first among finches. With its chinking call, it named itself into Old English as finc – or finch – a name that extended to other species. Centuries later, the poet Gerard Manley Hopkins was surely thinking only of chaffinches when he praised “finches’ wings” in his paean to ordinary contrasts, Pied Beauty.

And here they are, those diagnostic bars of white flashing against the coverts’ black, as the chaffinch lands on a twig in front of me. Sunrise intensifies all his colours: the slate-blue head, the rust breast, the olive rump. His gleaming blue-black bill opens and a wisp of breath pulses from his gape as he sings.

Walking here a few weeks ago, I heard a chaffinch – possibly this very one – sing the trickle of notes that marks the incomplete song of a first-year bird. I’m reminded of the pioneering research of the evolutionary biologist Peter Marler. Working initially on chaffinches in the 1950s, he showed that birdsong is shaped by learning and memory. Songbirds have an innate capacity to produce a version of their species’ song, but they are influenced by the types of songs they hear around them, and youngsters fine-tune their efforts to those of their elders. These cultural aspects of birdsong give rise to local dialects.

There’s another chaffinch singing in the distance. The songs of the two birds sound quite different, but, as their voices become more strident, “my” chaffinch slides his rendition closer to that of his rival’s. This could be a signal that he’s up for any contest. He tilts his head. The other chaffinch has switched to finks. My bird responds with warning huits. As the intruder emerges into view, both birds fall silent. Fluttering their wings and flicking their tails, they bob their face-off up and down the branches. Finally, they leap at each other and tumble through the air before swerving in opposite directions to vanish into the trees.

A friendly if slightly tuneless chirp is the most ubiquitous birdsong in British gardens with the house sparrow topping the Big Garden Birdwatch charts for the 21st consecutive year, according to the annual RSPB survey.

Blue tits, starlings, wood pigeons and blackbirds were the next most-sighted birds by more than 600,000 participants in the world’s largest wildlife garden survey.

The long-running citizen science project provides conservationists with invaluable data on how common species are faring. Although an average of four house sparrows were spotted in every garden when the survey was conducted in January, the number recorded has declined by nearly 60% since the survey began in 1979.

The starling, the third most seen bird this year, is on the UK red list of most threatened breeding bird species because of a sharp decline in its breeding population since the 1960s. It remains a popular visitor in winter, when birds arrive from northern Europe, but gardens and house roofs may be an increasingly important refuge for this declining species.

Gardens are an important habitat for many birds, covering an estimated 4,330 sq km in the UK, an area larger than the county of Somerset.

Beccy Speight, the chief executive of the RSPB, said: “Last year’s State of Nature report laid out a grim picture, finding that there’s been no let-up in the decline of our wildlife over recent decades, with one in six species at risk of being lost from Great Britain.

“However, with seven out of eight households lucky enough to have access to a garden, it is the place where many of us can make a positive difference to the ongoing nature crisis. Gardens and community green spaces can both give a crucial lifeline for struggling species by providing a huge patchwork of potential homes for nature.”

The US midwest typically spends the start of spring emerging from snow. But this year, after a warm winter left landscapes parched, the region instead was primed to burn. Hundreds of blazes ignited in recent months in states more accustomed to dealing with just dozens for this time of year, as extreme fire behavior defied seasonal norms.

Experts say the unusually early and active fire season was a symptom of El Niño, a climate pattern characterized by warmer surface temperatures in the Pacific Ocean that was predicted to supercharge global heating and extreme weather. But the climate crisis turned up the dial, and helped create conditions in the midwest where winter temperature records were not only broken – they were smashed.

“This was the strangest winter I have ever seen,” Stephen Marien, a predictive services fire meteorologist who works for the National Parks Service, said. Marien, a federal scientist based in Minnesota, added that he expected the season to trend warmer due to El Niño, but it was still shocking to see temperatures climb above 60F (16C) during the typically frigid months. For Marien it was a clear sign that “climate change has added fuel to the fire”.

The midwest – defined by the US census as Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota and Wisconsin – includes a range of landscapes, including grasslands, plains and forests, but the warmer weather had widespread impact.

The balmy start to the year left the region with a larger window for higher-risk fire conditions, which tend to peak in early spring after the snow melts but before trees and grasses “green up”. Vegetation that is normally hidden beneath the berms of snow was instead exposed to the sun weeks early and dried quickly. That unleashed unseasonal drought conditions and set the stage for the type of blazes that prove harder to contain.

In Minnesota, the agency responsible for coordinating fire suppression efforts said in a Facebook post that vegetation had dried out “roughly six weeks earlier than normal” and that firefighters in the state had already responded to 50 significant blazes in early March.

While the fires have mostly been small and numerous rather than catastrophic, they contributed to an early jump in burn totals across the country. More than 1.7m acres have already burned in the US, a number more than triple the 10-year average for this time of year, according to the National Interagency Fire Center (NIFC).

These numbers were driven in large part by the explosion of fires across Texas and Oklahoma, including the Smokehouse Creek fire that burned more than a million acres in cattle country and left tens of thousands of livestock dead. The fires in the midwest, though small by comparison, laid siege to landscapes and communities where the means needed to battle big blazes are limited. The early onset of fire season is a troubling trend.

“We’re not really having fire seasons any more. We’re just having fire years,” Ben Bohall, public information officer for the Nebraska forest service, told KCUR, an NPR affiliate in Kansas City, adding that resources, as a result, were strained.

In Nebraska, a fire in late February scorched more than 71,000 acres (29,000 hectares) in just 24 hours destroying several buildings including two homes. In March, three people were injured when several fires blew across roughly 3,000 acres in Minnesota.

The dangers continued in April. Fueled by drought and heat, a prescribed burn reportedly escaped control in Kansas this week, prompting evacuation notices and road closures. It is one of three active fires burning in the state, which have collectively charred roughly 15,000 acres. The danger is far from over.

“Calendar-wise it might seem like we are getting late into spring, but our fire season is still here in Kansas,” Chip Rebin, a meteorologist of the Kansas forest service, said in a broadcast update posted on Thursday. Temperatures are expected to soar in the coming week – potentially reaching 90F – with winds gusting at 40mph (65km/h) creating suppression complications and a high chance that contained fires will rekindle. “That’s a bad scenario,” he added, noting heat 20 degrees higher than normal “will rapidly dry out fuels”.

Fires burn differently in the region than those in California or other parts of the west, Marien said, and are typically snuffed out within the day. But intensifying fire conditions have created burns that are harder to contain. The local volunteer firefighters and state departments who battle these blazes can be quickly overwhelmed and may require outside resources, including aircraft, especially when embers are more difficult to extinguish.

“When you get longer-term droughts all the fuels on the ground can keep burning for quite a while,” he said, adding, “and that doesn’t happen often over here.”

While a spate of storms offered a reprieve in the northern states in recent weeks and the promise of rains returning in the coming months has cooled some of the dangers across the region in the short term, many states in the midwest are still experiencing dry conditions, which could worsen as the weather warms. The latest federal forecasts also show above normal temperatures are likely across much of the plains and Mississippi valley.

“It is the time of year when they are coming into their main wet season,” Andrew Hoell, a Noaa research meteorologist, said. But if those rains fail to appear, “you can fall into a drought and you can get some fires pretty quickly”.

As the climate crisis sets the stage for more extreme conditions, with climbing temperatures, sharper swings between wet and dry, and a thirsty atmosphere that evaporates moisture faster, the conditions that fueled these winter fires may arise more often.

“There’s no doubt that this is part of a trend,” Hoell said. “This part of the world is warming and it is warming during the winter time.” The extremes seen in the last season were boosted due to El Niño, so a repeat performance isn’t necessarily expected every winter. “But the background warming is there,” Hoell added, “and it’s here to stay.”

The people have spoken and the choice of Guardian readers for the final nominee for UK invertebrate of the year is resounding: all hail Lumbricus terrestris, the common earthworm.

The common earthworm – also known as the lob worm, dew worm, nightcrawler and, in Germany, the rain worm – is the soil-maker. Without its labours, we would struggle to feed ourselves.

Worms can bring 40 tonnes of soil to the surface per hectare a year in Britain. They are the engineers of an ecosystem that may be as diverse as the Amazon rainforest. Their diggings aerate soil and they pull fallen leaves and other organic matter into the earth and recycle them. Worms make soils less prone to flooding in winter and less baking hard in summer, they boost microbial activity and, of course, support plant growth.

But #VoteWorm is to celebrate majesty and dignity too. These are gorgeous creatures, many shades of pink, stretching out to 35cm long, and coiling and gliding – never “slithering”, as the pestilent centipede put it in James and the Giant Peach – through the earth.

The worm’s backers know this well. Lily, aged four, nominates the earthworm “because they help make compost to help our garden grow, they feel very soft and when they have got mud on them they are like a wiggly piece of string”.

We think the myopic adult world is blind to the brilliance of worms but they have long had influential advocates from Cleopatra and Charles Darwin to George Monbiot.

Today, Guardian-reading soil scientists and horticulturalists make a powerful case to Vote Worm but so, too, does Gill from North Wales, who has been earthworm-phobic since she was Lily’s age. “Much gratitude for all the thrashing ones, the little thready ones, the slimy ones, the knotted ones, the ones with ‘saddles’, the blue-tinged ones, even the enormous ones stretching terrifyingly across my drive when the ground is sodden,” she writes. “Thank you all, for what you do.”

Take heed of Trevor Lawson from Amersham. Not only are earthworms critically important, he argues, they are “the best symbol of everything that matters about being an invertebrate in our anthropocentric worldview – vulnerable, crushable, rarely considered, even despised for their apparent blind ignorance, and yet through sheer force of numbers and extraordinary evolutionary adaptation, they are capable of shaping the entire world around us as we, in our own wilful ignorance, stumble blindly on.”

#VoteWorm’s last word goes to reader Jacqui from Wiltshire who says: “200 words for this hero?! Really! Give the worm a gong!”

• At midnight on Friday 12 April, voting will open to decide the Guardian’s UK invertebrate of the year with the winner to be announced on Monday 15 April.