スミソニアン博物館さんのインスタグラム写真 - (スミソニアン博物館Instagram)「Did you know a dragonfly is an indicator species? Indicator species offer clues about specific conditions and changes in an environment. Scientists use them to diagnose problems such as disease outbreaks, pollution, and habitat loss or fragmentation. ⁣ ⁣ Dragonflies indicate the presence of freshwater. Their absence often points to signs that a body of water has excessive nutrients, such as a byproduct of agricultural runoff, or is contaminated with pesticides.⁣ ⁣ You can play a role in protecting dragonflies and their freshwater homes by volunteering with local wetland support groups, minimizing pesticide use, and reducing your carbon footprint by walking, biking and utilizing public transit when possible.⁣ ⁣ Make sure to follow us at @smithsoniangardens so you can keep up with everything going on in our gardens and landscapes!」5月21日 20時29分