SOME of the country’s most widespread ladybird species have suffered significant declines in the past two decades, the first atlas of the insect showed.

The new publication maps all 47 different ladybirds in Britain and Ireland, and reveals that in the UK more than a fifth — 10 species — have been decreasing in the past 20 years.

They include the widespread 14-spot and 10-spot ladybirds,and rarer species such as the hieroglyphic ladybird.

And, since the arrival in the UK in 2004 of the invasive Asian harlequin ladybird which came from the continent where it was being used to control pests, the two-spot has also been in decline.

Harlequins compete for food and prey on the larvae of other, smaller species such as the two-spot. The harlequin ladybird population has exploded since its arrival and there are now 25,676 records of its presence across the country. The figure puts it only second to the most commonly recorded species, the seven-spot ladybird (pictured), which has 27,000 records in Britain and Ireland in data stretching over the last century. Experts believe the arrival of species such as the harlequin are among the reasons for declines in numbers, along with changes to habitat and, potentially, changes in the climate.

Dr Helen Roy, from the Centre for Ecology and Hydrology (CEH) and one of the authors of the atlas, the result of a six-year research project, said: “What’s quite striking is that in the same way as butterflies and moths have seen very common species going into decline, we’re seeing the same happen with ladybirds.

“They are telling us there are changes going up through the food chain. Ladybirds can be used as indicators of wider changes in our environment.”

Dr Roy said the atlas showed five species were increaseing with those such as the orange ladybird, potentially benefiting from a warmer climate.