スミソニアン国立動物園さんのインスタグラム写真 - (スミソニアン国立動物園Instagram)「🐺 Aaarrrooo! DYK a gray wolf’s howl can be heard by other wolves from 7 miles away?👂 Howling stimulates a hunt and can be used as a long-distance territorial expression. 🐺 You don’t have to travel that far to learn more about these canines! Check them out in @ZooGuardians and establish your own pack today! 📱#ZooGuardians is free to download from both the Google Play and Apple App Store.」10月20日 5時46分