How Bison Are Helping Cliff Swallows Build Their Nests

Name: How Bison Are Helping Cliff Swallows Build Their Nests
Uploaded: 2020-09-02
Duration: 218000
Description: It's a partnership that's as unlikely as any: herds of bison on the move are kicking up chunks of earth. This, in turn, gives cliff swallows the valuable mud pellets they need to build their nests.

It's a partnership that's as unlikely as any: herds of bison on the move are kicking up chunks of earth. This, in turn, gives cliff swallows the valuable mud pellets they need to build their nests. (03:38)