HOW many butterflies are there in Hampshire?

That is the question Sir David Attenborough wants people to help him answer by taking part in a mass survey.

He is urging the public to take part in this year’s Big Butterfly Count, which runs until August 7.

But the legendary broadcaster and naturalist is warning that this year’s slow spring and soggy summer could pose a risk to the common butterflies found across Hampshire and the Isle of Wight.

Cold, wet weather can have a disastrous effect on butterfly numbers as the conditions reduce their opportunity to feed and mate.

This year butterflies have endured a slow start to spring with cold conditions experienced during March and April.

Despite a few warm weeks in May, June was a washout for many parts of the UK with sightings of butterflies down on previous years.

This year’s soggy weather follows on from last year’s colder than average summer, meaning a sustained spell of warm and dry weather is much needed to help our common butterfly species mount a recovery.

The Big Butterfly Count is the world’s largest butterfly survey, which encourages people to spot and record 18 species of common butterflies and two day-flying moths during three weeks of high summer.

It can be done in any green space, but people are also being invited to take part at a number of free public butterfly events.

Butterfly Conservation president Sir David said: “During my lifetime I have seen first-hand how the UK’s once plentiful butterflies have dwindled and diminished, with some species even becoming extinct. This is a gloomy outlook but not one that is set in stone. We must make sure these losses are halted and reversed, but in order to achieve this we first need to find out as much information about our butterflies as possible.”

More than three-quarters of the UK’s butterflies have declined in the past 40 years with some common species, such as the small tortoiseshell, suffering significant slumps.

The Big Butterfly Count, now in its seventh year, helps Butterfly Conservation find out how common species are faring and how to best protect them in the future.

More than 50,000 people took part last year, counting around 600,000 butterflies.

To take part all people have to do is find a sunny spot and spend 15 minutes counting the butterflies they see and then submit sightings online at bigbutterflycount.org or via the free Big Butterfly Count app.