The world of butterflies is full of remarkable with often unknown facts and details. Worldwide, even today the butterflies are inadequately represented on the International Union for Conservation of Nature (IUCN) Red list of Threatened Species. There are 20,000 described species out of which only 978 are assessed and of these assessed species 18% (173) are listed as threatened (WWF 2020).
The WWF Living Planet Report 2020 focusing on European butterflies, the 2020 Butterfly Living Planet Index shows a decline of 49% between 1990 and 2017 for the 17 grassland butterfly species from 16 European countries. The decline is largely been caused by agricultural intensification and the loss of grasslands according to the report.
About the butterflies in rest of the world, the LPR 2020 reports numbers declining at 2% per year with 33% reduction in numbers between 1996 and 2006 from the regular butterfly counts in Ohio, USA. The report also states that ongoing assessment of extinction risk of the swallowtails in the family Papilionidae, so far shows 14% of the 36 birdwing butterfly species in the world are threatened with extinction.
Source | WWF (2020) Living Planet Report 2020 - Bending the curve of biodiversity loss.
Almond, R.E.A., Grooten M. and Petersen, T. (Eds). WWF, Gland, Switzerland.
In Pics | The National Butterfly of Bhutan, Ludlowi’s Bhutan Glory (𝐵ℎ𝑢𝑡𝑎𝑛𝑖𝑡𝑖𝑠 𝑙𝑢𝑑𝑙𝑜𝑤𝑖 Gabriel 1942) | Since its first discovery in 1933-1934 from eastern Bhutan, no records were made for nearly a century. It was rediscovered in 2009 (after 75 years) from the same place,Tashiyangtse. In 2012 the species was reported form west Kemang District, western Arnunchal Pradesh, India. And, in August 2020 it was reported from Bumthang. This species is listed as endangered on the IUCN Red List of Threatened Species.
