the orchard oriole , icterus spurius , is the smallest north american species of icterid blackbird .
the subspecies of the caribbean coast of mexico , i .
s .
fuertesi , is sometimes considered a separate species , the ochre oriole .
this species is 6.3 inches (16 cm) long and weighs 20 g .
the bill is pointed and black with some blue-gray at the base of the lower mandible (howell and webb 1995) .
the adult male of the nominate subspecies has chestnut on the underparts , shoulder , and rump , with the rest of the plumage black .
in the subspecies i .
s .
fuertesi , the chestnut is replaced with ochre (howell and webb 1995) .
the adult female and the juvenile of both subspecies have olive-green on the upper parts and yellowish on the breast and belly .
all adults have pointed bills and white wing bars .
(orchard orioles are considered to be adults after their second year .
) one-year-old males are yellow-greenish with a black bib .
the breeding habitat is semi-open areas with deciduous trees .
i .
s .
spurius breeds in spring across eastern north america from near the united states-canada border south to central mexico .
a 2009 study also found breeding in the thorn forest of baja california sur and the coast of sinaloa during the summer "monsoon"; this region had previously been thought to be only a migratory stopover (rohwer , hobson , and rohwer , 2009) .
i .
s .
fuertesi breeds from southern tamaulipas to veracruz (howell and webb 1995) .
these birds enjoy living in shaded trees within parks along lakes and streams .
the nest is a tightly woven pouch attached to a fork on a horizontal branch .
their nests tend to sit close together .
the nominate subspecies' winter range extends from the coastal lowlands of central sinaloa and southern veracruz south to northern colombia and northwestern venezuela (scharf and kren 1996) .
the ochre subspecies has been observed in winter on the pacific slope of mexico (howell and webb 1995) .
nominate orchard orioles depart from their winter habitats in march and april and arrive in their breeding habitats from late april to late may .
usually , they leave their breeding territories in late july and early august and arrive on their winter territories in mid august .
these birds are nocturnal migrants .
while in breeding season , they eat insects and spiders .
when the season changes , their diet also includes ripe fruit , which quickly passes through their digestive tract .
during the winter , their diet consists of fruit , nectar ,and insects .
when in flight , orchard orioles generally swoop close to the ground and fly at or below treetop levelduring courtship , females display themselves in 3 unique ways .
the first way is bowing their head and torso toward the male .
seesawing , the second courtship display , involves repetitively alternating lowering and raising the head and tail .
the third display is begging , which is fast-paced fluttering of wings halfway extended , followed by a high whistle .
the specific name spurius refers to the original misidentification of the male as a female baltimore oriole .
these birds are sometimes mistakenly identified as new world warblers .
