Conservationists have produced a league table to show the winners and losers amongst Wales' butterfly population.
Numbers of the marsh fritillary butterfly have declined
Species which have suffered the biggest decline, such as the high brown and pearl-bordered fritillaries, are those which rely on particular habitats.
However, more common and mobile butterflies like the red admiral have seen numbers rise by 30% in 25 years.
The nine-year survey involving thousands of volunteers followed up a similar one ending in the early 1980s.
Butterfly Conservation Wales said it was working on projects to protect habitats and save the rarest species.
It points to the Mynydd Mawr Marsh Fritillary Project at Cross Hands in Carmarthenshire, which helps landowners to sensitively manage their wet meadows for the butterfly.
The five-year project, supported by the Countryside Council for Wales, also involves graziers, contractors and volunteers.
WINNERS AND LOSERS
Painted lady (+31%)
Red admiral (+30%)
Marsh fritillary (-32%)
Pearl-bordered fritillary (-77%)
High brown fritillary (-82%)
Source: Butterfly Conservation, figures for 1995-2004 survey, compared to 1970-1982
Russel Hobson, senior conservation officer for Butterfly Conservation Wales said: "We've seen some progress in Wales in the marsh fritillary, which seems in terminal decline in England, but we have only two sites for the high brown and nine for the pearl-bordered Fritillary.
"We have active conservation at all these sites."
"At our Eyarth Rocks nature reserve in Denbighshire they have spent four hard winters managing scrub and as a result have seen numbers of the pearl-bordered fritillary reach their highest numbers in 30 years," he added.
The charity said butterflies were key indicators of the health of the environment.
But it would like to see the assembly government set up schemes for farmers to help them manage habitats for butterflies, as well as birds and bats.
The research for Wales is taken from the charity's new report, State of Butterflies in Britain and Ireland, which was compiled from data gathered by thousands of volunteer recorders and conservationists at more than 500 sites.
Mr Hobson said: "This has been a huge effort, we had 1.4m recordings in 2000-2002 alone and it's still ongoing and we still need people to take part."