Another wet summer has meant a “dreadful” year for butterflies, according to a conservation expert.

Matthew Oates, of the National Trust, said that rain and wind this year and last had harmed many species. although others, including the cabbage white, had had a good summer.

Mr Oates has been surveying British butterflies for a series being broadcast this week on BBC One, on The One Show. “Butterflies are very fragile and succumb to heavy rain and strong winds. Next year’s butterflies are out as baby caterpillars, and it may well be that very heavy rain washes off eggs and in particular young caterpillars – or they get diseases,” he said. “The last two summers have been blighted by rain and wind that seriously affected their fortunes. Some species have managed to overcome the odds. Overall, it has been a dreadful year, probably the worst in my 45-year experience.” He said that many species were under threat, and efforts to create hospitable habitats were hampered by unseasonable spring and summer weather.

A gale early last month and subsequent deluges damaged the high brown fritillary. The bad year for the swallowtail butterfly was probably caused by the wet July last year killing young caterpillars. The purple emperor butterfly had a good start but the strong winds in July seriously depleted its numbers.

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