What is the title of the work You mentioned?

p.s. If You have the link of the www from where the pdf of the publication can be downloaded, please let me know about it.

Thank you!

The European Grassland Butterfly Indicator: 1990…-2011 can be found here:

http://www.eea.europa.eu/publications/the-european-grassland-butterfly-indicator-19902011

for the department of Côtes d'Armor, an inventory was conducted in 1912 by Oberthur. In 2003, the network of naturalists showed a loss of 25% of species.

If you have some references and/or internet link for this kind of inventory, I would be very interested. Thank you.

Here you can find some information about the trends of butterflies in Europe:

http://www.nature.com/nclimate/journal/v2/n2/full/nclimate1347.html