There are 36 known species of butterfly in north Wales
Britain's best known naturalist Sir David Attenborough is urging residents of north Wales to get involved in Save Our Butterflies Week from 25 July to 1 August.
And Wales' own TV wildlife expert Iolo Williams will be visiting Colwyn Bay to lend his support to the campaign.
Sir David, who's president of charity Butterfly Conservation, is urging people to count the butterflies in their gardens to help build up a picture of which are flourishing and which are not.
"Butterflies are extraordinary, heart-lifting creatures - visions of beauty and visions of summer," he said.
"Butterflies in profusion tell us all is well with nature. When they decline it's a warning that other wildlife will soon be heading the same way.
"So with the Big Butterfly Count we'll be doing more than just counting butterflies - we'll be taking the pulse of nature. "
Iolo Williams will be attending a free event at Wynn Gardens, Colwyn Bay, on Sunday 25 July.
Iolo will be at Wynn Gardens, Colwyn Bay on Sunday 25 July, 2-4pm
"Iolo's always been great at supporting us," said Jan Miller, a volunteer for Butterfly Conservation who designed the special plant bed in Wynn Gardens to attract more butterflies to the area.
And with seven out of every ten butterflies in the UK under threat, Jan thinks we can all do our bit to help save the species.
"Their decline is mainly due to the loss of habitat," she explained. "Intensive farming and lots of building work since the war means wild flowers have been squeezed out. All the Tarmac in towns is like a desert to the butterflies.
"So it's important for people in towns to have butterfly-friendly plants in their gardens to provide a stepping-stone for them through the concrete jungle."
She and Iolo will be on hand to suggest plants that will attract butterflies to you garden.
"What's really been lost in the countryside is wild flowers," said Jan. "They're a great food source for caterpillars.
"Birds-foot trefoil, like a miniature yellow sweet pea, is great for the larvae of the common blue butterfly, which isn't so common anymore. Or there's red and white clover which you could let grow on your lawn,
"Some are so pretty, and you can grow them in a border or a pot."
Garden flowers provide nectar and Jan emphasises the importance of having something in bloom throughout the summer, so the butterflies have a constant source of food.
Numbers of one rare butterfly have quadrupled at the charity's Ruthin reserve
"Everyone knows about buddleia which flower late in the summer, but you also need some honesty or the Bowles Mauve wallflower which flower in spring," she said.
With Iolo's help, Jan hopes to dispel many people's belief that insects are nasty, bighting creepy crawlies they don't want around.
"We want to get people to be a bit more tolerant of insects because they're an important part of the food chain. Birds rely on caterpillars to feed the chicks - it all has a knock-on effect."
To take part in the butterfly count go to the
Butterfly Conservation website
"You can print off a colour ID chart of all the butterflies and log in what species you've spotted locally," said Jan, who's included more detailed diagrams of butterflies in her book, Gardening for Butterflies, Bees and other Beneficial Insects.
"The drawings are full of arrows to show you which features to look out for when they fly by. Once you've figured that out, you'll be able to spot the differences and appreciate them much more."