Willow emeralds were spotted last month near the Roger Mitchell Hide and in Loversall Field. They’re likely to be around until mid-autumn, but you’ll need to be keen-eyed to find one: unlike other damselflies, they spend most of their time in the trees - basking on the sunniest branches of alders and willows, where their metallic green plumage blends in well.

Even in winter, you might notice signs of their presence. Females make distinctive scars in the branches by laying eggs, which remain in the bark throughout the winter. When spring arrives, the eggs hatch and the larvae fall into the water below.

Even if you don’t manage to spot a willow emerald, you’ve still got an excellent chance of seeing some of the larger and showier dragonflies that patrol Potteric Carr’s lakes, ponds and ditches on warm sunny days. The willow emerald’s arrival means 23 species of dragonfly and damselfly have now been recorded on the reserve – five more than a couple of decades ago. 

So, why are there more of these beautiful and fascinating insects around?  It’s partly a testament to the hard work done at Potteric Carr to create a healthy environment in which they’ll thrive – dredging ponds and clearing scrub from their edges. But climate change is also playing a major part here. As the UK gets warmer and drier, some species can make their home in areas they previously would have found inhospitable.

Willow emerald damselflies are a classic example. It’s just 13 years since significant numbers first made their way to the UK from Europe (in another heatwave summer, incidentally) and settled in East Anglia. Since then, as temperatures rise, they’ve moved north and west, and experts had been predicting it was only a matter of time before they reached Potteric Carr.

It’s a trend that’s already been followed by another damselfly, the small red-eyed. This species was first recorded in the UK in 1999, and then spread spectacularly through south east England before moving north. It was first spotted at Potteric Carr three years ago, and there are now thought to be more than 100 individuals on the reserve.

This shift northwards because of climate change isn’t just limited to insects. The same phenomenon brought two bird pioneers to Potteric Carr this year. A pair of rare black-winged stilts arrived in May, delighting birdwatchers by nesting on Piper Marsh and raising four chicks. 

It’s believed to be the furthest north in the UK that these elegant waders have ever successfully bred. You’d normally expect to find them around the Mediterranean. But conservationists think they may have been displaced by very hot weather drying out their wetland habitat in Spain, or a prolonged spell of southerly winds driving them north, or a combination of the two.

The powerful forces unleashed by climate change have brought exciting new arrivals – but they’ve been bad news for other species.

Willow tits are Britain’s most threatened resident birds. Their numbers have declined by a staggering 94% since the 1970s, and Potteric Carr – where they once thrived – has just two or three territories left. They need to breed in wet woodland, and that’s being destroyed as the climate turns hotter and drier.

Potteric Carr is a wetland – a precious wildlife environment. Wander around it at the moment, though, and you’ll find many of its ponds and pools are drier than usual at this time of year. As Yorkshire has officially been declared a drought zone, there’s a danger that the same climate changes that have brought new species here could also make life harder for many of its animals in the future.