Lucy's warbler (''Leiothlypis luciae'') is a small New World warbler found in

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

. This species ranges includes

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural list of regions of the United States, region of the United States that includes Arizona and New Mexico, along with adjacen ...

and northwestern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. It is one of only two warblers to nest in cavities.

Description

Lucy's warbler is the smallest species of New World warbler. It measures from in length and can weigh from , thus being slightly smaller even than the warblers formerly placed in the genus ''

Parula ''Parula'' was formerly a small genus of New World warblers which breed in North America, North and South America. In 10th edition of Systema Naturae, 1758, Carl Linnaeus, Linnaeus classified the northern parula as a titmouse, tit, ''Parus ameri ...

''. Among standard measurements, the wing chord is , the

tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...

is , the bill is and the tarsus is . It is rather undistinguished compared to other wood-warblers, being perhaps the palest species in its family. Its head and upperparts are pale gray, while the underparts are whitish. It has a white eyering and a small, pointed bill. Both genders have a rufous rump, a diagnostic field mark. Adult males also have a small rusty patch on their crown. Juveniles are paler, with a tawny rump and buffy wingbars. Lucy's warbler is closely related to Virginia's warbler, Nashville warbler and Colima warbler. The common name and binomial of this species commemorate Lucy Hunter Baird, daughter of ornithologist

Spencer Fullerton Baird Spencer Fullerton Baird (; February 3, 1823 – August 19, 1887) was an American naturalist, ornithologist, ichthyologist, Herpetology, herpetologist, and museum curator. Baird was the first curator to be named at the Smithsonian Institution. He ...

. Lucy's warblers inhabit

riparian A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a ripar ...

mesquite Mesquite is a common name for some plants in the genera ''Neltuma'' and '' Strombocarpa'', which contain over 50 species of spiny, deep-rooted leguminous shrubs and small trees. They are native to dry areas in the Americas. Until 2022, these ge ...

and brushy country of the

and northwestern

. It can nest in the driest vegetated stretches of the Sonora Desert and nest in possibly the driest habitats of any New World warbler.

Life history

Lucy's is the only warbler besides

prothonotary A prothonotary is the "principal clerk of a court," from Late Latin, L.L. ''prothonotarius'' (Wiktionary:circa, c. 400), from Greek ''protonotarios'' "first scribe," originally the chief of the college of recorders of the court of the Byzantine E ...

to nest in cavities. It uses natural cavities in cactus or trees or holes excavated by

woodpecker Woodpeckers are part of the bird family (biology), family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme ...

s or verdin in prior years. Unlike the prothonotary, Lucy's warbler has been known to utilize man-made nest boxes, even using a hollowed-out gourd. If using a woodpecker hole, the warbler may fill the cavity almost entirely with debris and put the nest on top so the small birds can see outside of it. This species nests in some of the densest aggregations of any warbler, with as many as 12 pairs per ha (5 pairs per acre). The birds

migrate Migration, migratory, or migrate may refer to: Human migration * Human migration, physical movement by humans from one region to another ** International migration, when peoples cross state boundaries and stay in the host state for some minimum le ...

to western Mexico in winter.Robbins, C., B. Bruun, H. Zim. 1996. ''Birds of North America''. New York: Western Publishing Company. These strictly

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores we ...

birds forage actively, looking for the

caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder ...

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

s, and

leafhopper Leafhopper is the common name for any species from the family (biology), family Cicadellidae: based on the type genus ''Cicadella''. These minute insects, colloquially known as hoppers, are plant feeders that suck plant sap from grass, shrubs, or ...

s that compose much of their diet. When they capture a caterpillar, they shake it vigorously and skin off the prickly hairs on the back before consumption. Habitat loss is the main threat to this species, with riparian habitats in its range being developed extensively. To a lesser extent,

brown-headed cowbird The brown-headed cowbird (''Molothrus ater'') is a small, obligate brood parasitic icterid native to temperate and subtropical North America. It is a permanent resident in the southern parts of its range; northern birds migrate to the souther ...

parasitism Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

is also threatening this species. Populations are diminishing throughout its breeding range.

References

External links

Lucy's warbler photo gallery
VIREO {{Taxonbar, from=Q27075892 Leiothlypis Native birds of the Western United States Fauna of the Chihuahuan Desert Fauna of the Sonoran Desert Fauna of the Lower Colorado River Valley Lucy's warbler Lucy's warbler