Biodiversity Day
The United Nations has proclaimed May 22 The International Day for Biological Diversity (IDB) to increase understanding and awareness of biodiversity issues.
This is part of the UN Decade of Biodiversity - from 2011-2020, with the target "By 2020, at the latest, people are aware of the values of biodiversity and the steps they can take to conserve and use it sustainably."
List of past Biodiversity Day themes: International Day for Biological Diversity - 22 May (cbd.int)