0 the orchard oriole , icterus spurius , is the smallest north american species of icterid blackbird .
1   the subspecies of the caribbean coast of mexico , i .
2  s .
3  fuertesi , is sometimes considered a separate species , the ochre oriole .
4 this species is 6.3 inches (16 cm) long and weighs 20 g .
5   the bill is pointed and black with some blue-gray at the base of the lower mandible (howell and webb 1995) .
6  the adult male of the nominate subspecies has chestnut on the underparts , shoulder , and rump , with the rest of the plumage black .
7  in the subspecies i .
8  s .
9  fuertesi , the chestnut is replaced with ochre (howell and webb 1995) .
10    the adult female and the juvenile of both subspecies have olive-green on the upper parts and yellowish on the breast and belly .
11  all adults have pointed bills and white wing bars .
12  (orchard orioles are considered to be adults after their second year .
13 ) one-year-old males are yellow-greenish with a black bib .
14 the breeding habitat is semi-open areas with deciduous trees .
15  i .
16  s .
17  spurius breeds in spring across eastern north america from near the united states-canada border south to central mexico .
18   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) .
19  i .
20  s .
21  fuertesi breeds from southern tamaulipas to veracruz (howell and webb 1995) .
22  these birds enjoy living in shaded trees within parks along lakes and streams .
23  the nest is a tightly woven pouch attached to a fork on a horizontal branch .
24  their nests tend to sit close together .
25  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) .
26   the ochre subspecies has been observed in winter on the pacific slope of mexico (howell and webb 1995) .
27 nominate orchard orioles depart from their winter habitats in march and april and arrive in their breeding habitats from late april to late may .
28  usually , they leave their breeding territories in late july and early august and arrive on their winter territories in mid august .
29  these birds are nocturnal migrants .
30 while in breeding season , they eat insects and spiders .
31  when the season changes , their diet also includes ripe fruit , which quickly passes through their digestive tract .
32  during the winter , their diet consists of fruit , nectar ,and insects .
33 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 .
34  the first way is bowing their head and torso toward the male .
35  seesawing , the second courtship display , involves repetitively alternating lowering and raising the head and tail .
36  the third display is begging , which is fast-paced fluttering of wings halfway extended , followed by a high whistle .
37 the specific name spurius refers to the original misidentification of the male as a female baltimore oriole .
38  these birds are sometimes mistakenly identified as new world warblers .
