Tennessee Warbler

Look for

A small, plain olive-green warbler — clean white underparts, no wing bars, thin pointed bill, white supercilium (eyebrow stripe), grayish head. Deceptively subtle — more like a vireo than most warblers.

Size: ~4.75" — tiny, smaller than a sparrow.

Listen for

• Song: a loud, staccato three-part "tsip-tsip-tsip... swit-swit-swit... chew-chew-chew-chew" — mechanical, staccato, accelerating.

Where in Memphis

Migration only. Tennessee Warblers pass through in late April–early May and mid-September–early October. They breed in the boreal forest of Canada, winter in Central America — they do not breed in Tennessee.

• Overton Park Old Forest
• Meeman-Shelby, Wolf River
• Shelby Farms woodland edges

Behavior

• Canopy gleaners — work branches and leaf clusters 20–60 ft up.
• Nectar drinkers in winter — important pollinators of tropical flowers in Mexico and Central America.
• Among the most abundant warblers passing through Memphis in May.

Story

The misleading name

Alexander Wilson collected the first specimen near Nashville on the Cumberland River in 1811 — on migration, not a breeding bird. He named it Tennessee Warbler, and the name stuck even though no Tennessee Warblers breed in Tennessee.

Classic example of collection-site nomenclature creating permanent confusion. (See also: Magnolia Warbler.)

The spruce-budworm connection

Their populations boom and bust with outbreaks of spruce budworm in the Canadian boreal forest. A boom year for budworms = a bumper year of Tennessee Warblers passing through Memphis.

The Memphis spring list

Every mid-May Overton Park birder finds several Tennessee Warblers mixed with American Redstarts, Magnolia Warblers, and Chestnut-sided Warblers. The song is often the first ID — look is hard, song is unmistakable.

Fun facts

• They winter in shade-coffee plantations — a major conservation argument for buying shade-grown coffee.
• A Tennessee Warbler weighs about 9 grams — less than two nickels.
• They migrate across the Gulf of Mexico at night, nonstop.
• Oldest known wild Tennessee Warbler: 7+ years.