ムナジロホロホロチョウ 対 Eastern Crested Guineafowl

The most reliable field mark to separate these two is the presence of a distinctive black crest on the head of the Eastern Crested Guineafowl, which is completely absent in the White-breasted Guineafowl. In addition, the Eastern Crested Guineafowl shows a densely white-spotted blackish plumage, while the White-breasted Guineafowl is mostly black with a contrasting white breast and lacks spots. Both species are similar in overall shape and terrestrial habits, but the head and breast pattern are the quickest ways to distinguish them, even at a distance. Juvenile/immature wing patterns are not described as diagnostic for either species in the available notes.

1. Crest presence: Eastern Crested Guineafowl always shows a prominent black crest of curly feathers on the crown; White-breasted Guineafowl has a bare, red head with no crest. This is the fastest and most reliable field mark at any age or season.
2. Breast color: White-breasted Guineafowl has a sharply defined white breast contrasting with the rest of its black plumage. Eastern Crested Guineafowl lacks a white breast; its underparts are spotted like the rest of the body.
3. Body spotting: Eastern Crested Guineafowl is densely covered in small white spots over a blackish background, visible even at a distance. White-breasted Guineafowl is plain black except for the white breast—no spots on the body.
4. Head color: White-breasted Guineafowl has a small, bare, red head; Eastern Crested Guineafowl's head is mostly black with the crest and may show less bare skin.
5. Tail: Both species have long, black tails, but this is not a strong separator.
6. Bill and feet: White-breasted Guineafowl has a greenish-brown bill and greyish feet, but these are subtle and rarely diagnostic in the field.
7. Size: Eastern Crested Guineafowl is slightly larger and bulkier, but size overlap is considerable and not reliable for single birds.
8. Sexes: Both species are sexually similar; female White-breasted Guineafowl is only slightly smaller than the male.
9. Juvenile/immature plumage: No distinctive age-specific marks are described for either species, so do not rely on immature wing or flight patterns for separation.
10. Flight vs. perched: Both are terrestrial and rarely fly, but when flushed, the crest and spotted plumage of Eastern Crested Guineafowl remain visible; White-breasted Guineafowl's white breast may flash in flight.
11. Habitat: If in East African open forests, woodlands, or forest-savanna mosaics, Eastern Crested Guineafowl is more likely, but habitat is not diagnostic alone.
12. Range: Eastern Crested Guineafowl is restricted to East Africa (Somalia to Tanzania and nearby islands); White-breasted Guineafowl is not described in detail but is not native to this range.
13. Common pitfalls: Do not confuse the white breast (only in White-breasted) with the white spots (only in Eastern Crested). The presence or absence of a crest is the quickest check.
14. Crest confusion: Be aware that the term "crested" is sometimes misapplied to other guineafowl species, but only Eastern Crested Guineafowl in this pair has the true black crest.
15. Group context: Both species may be seen in small flocks, but this does not aid separation.

Eastern Crested Guineafowl is slightly larger, with a total length of about 50 cm and a weight range of 721–1,543 g [wikipedia], compared to the White-breasted Guineafowl at up to 45 cm [wikipedia]. The difference is subtle in the field, but the Crested is generally bulkier and longer. Sexes are similar in both, though female White-breasted Guineafowl are a bit smaller than males.

• Juvenile/immature wing pattern: No age-specific upperwing or flight pattern differences are described for either species in the sources.
• Adults: White-breasted Guineafowl is mostly black with a striking white breast, a small bare red head, and a long black tail. The Eastern Crested Guineafowl is blackish overall but densely covered in small white spots, and has a prominent black crest of curly feathers on the head. The breast is not white and blends with the rest of the spotted plumage. Bill and feet are greenish-brown and greyish, respectively, in White-breasted Guineafowl, but these are subtle in the field. Both sexes look similar in each species.

Both species are terrestrial and spend most of their time on the ground. No major behavioral differences are highlighted in the available notes that would help with identification in the field.

White-breasted Guineafowl is not described in detail for habitat in the notes, but the Eastern Crested Guineafowl is found in East Africa, inhabiting open forests, woodlands, and forest-savanna mosaics [wikipedia]. If seen in these habitats in Somalia to Tanzania and nearby islands, Eastern Crested is more likely. Habitat alone is not diagnostic where ranges overlap or are uncertain.