The slender-billed grackle is an extinct species of grackle in the Icteridae family of birds. The species was closely related to the western clade of the great-tailed grackle, from which it diverged quite recently, around 1.2 million years ago. It weighed 2.5 oz to 5 oz.
Region
Central Mexico
Typical Environment
Historically confined to freshwater marshes, lake margins, and canal systems around the Valley of Mexico, including Lake Texcoco and Xochimilco. It frequented dense stands of reeds and bulrush, as well as adjacent agricultural plots and village edges. The species used emergent vegetation for nesting and roosting and foraged along muddy shorelines and shallow waters.
Altitude Range
2000–2500 m
Climate Zone
Highland
Ease of Keeping
Beginner friendly: 1/5
The slender-billed grackle was endemic to the marshes of the Valley of Mexico and went extinct in the early 20th century after extensive drainage of lakes and wetland loss. It was closely related to the western clade of the great-tailed grackle, diverging roughly 1.2 million years ago. Its notably narrow, elongated bill and preference for reedbeds set it apart from its relatives.
Male by José Mariano Mociño
Female
Temperament
social and noisy
Flight Pattern
strong flier with steady wingbeats and fanned tail
Social Behavior
Formed flocks outside the breeding season and gathered in communal reedbed roosts. Nested in colonies among dense emergent vegetation; males likely displayed prominently from exposed perches. Pairs tended to nest near water, using reeds and grasses to build cup nests.
Migratory Pattern
Resident
Song Description
Vocalizations were a mix of sharp whistles, creaks, and metallic chatters typical of grackles. Males produced varied, loud calls during display and at communal roosts.
Plumage
Males glossy with iridescent black-purple sheen; females and immatures duller brown with lighter underparts. Overall sleek build with a distinctly narrow, elongated bill and long tail typical of grackles.
Diet
An opportunistic omnivore, feeding on aquatic and terrestrial insects, snails, and other invertebrates. It also took grains and seeds, including maize, and likely scavenged small amounts of human food waste. Foraged by probing mud, gleaning from vegetation, and picking items from the water surface.
Preferred Environment
Favored the edges of lakes, canals, and marshes with abundant reeds and shallow water. It also foraged in nearby agricultural fields and along village margins where food was accessible.
