Numbers of dragonfly species are increasing across Britain and Ireland, and experts warn this is largely due to climate change.
A new report by the British Dragonfly Society (BDS) found that more than 40% of resident and regular migrant species have increased since 1970.
Just 11% of species have declined.
Other species have spread north into areas such as Ireland and Scotland, the report found.
The researchers warn that the statistics show the impact of climate change: dragonflies are a tropical group of insects, and benefit from rising temperatures.
Dave Smallshire, co-editor of the report told the BBC: "The increase in many species, if not all, we can put down to a combination of climate warming and more or better wetland habitats such as an increase in the number of ponds, lakes, gravel-pits and reservoirs in recent decades.
"The overwhelming message is that global climate change – and in the case of Britain and Ireland – significant climate warming is likely to have had an overriding effect on many of these changes.”
The emperor dragonfly has shown the largest increase.
Found mainly in England and south Wales until the 1990s, the species crossed the Irish Sea in 2000, before spreading rapidly through Ireland.
It has also spread northwards in England and Wales, reaching Scotland in 2003.
The researchers also say that several new species have colonised Britain including small red-eyed damselfly, willow emerald damselfly and southern migrant hawker.
The researchers wrote: "This increased rate of immigration and colonisation by species with a more southern distribution in Europe is unprecedented in modern times and clearly shows how our climate is changing to one more commonly found on the continent."
The State of Dragonflies 2021 report covers a 50-year period from 1970 to 2019 and is based on more than 1.4 million dragonfly records from 17,000 recorders.
The boom in dragonfly numbers comes against a broader background of declining insect numbers.
A report in 2019 found that 40% of insect species are declining, with a third endangered, according to a global scientific review of research.
Researchers in Europe became aware of how serious the decline in insect numbers was in 2011 – and say that since then it has ‘got worse’.
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