For over a century, the Audubon's Warbler (of the West) and the (of the East) were thought to be two completely different species.
The Audubon’s warbler carries a secret in its DNA. While most warblers must fly to the tropics to find insects in winter, the Yellow-rumped warbler has evolved to digest (like bayberry and juniper). This allows it to stay much further north than its cousins, making it one of the first signs of spring for many birders. The "Family Tree" Twist audubon's warbler
In 1973, scientists discovered a "hybrid zone" in the Canadian Rockies where these two birds were meeting and having healthy, fertile offspring. This led to a dramatic scientific "lumping." They were stripped of their species status and merged into one: the —affectionately known by birders as the " butterbutt " for the bright yellow patch on its tail. 🧬 A Remarkable Survival Strategy For over a century, the Audubon's Warbler (of