The Sri Lanka Jungle-fowl (Gallus lafayetii) is of the same genus as the domestic chicken, Gallus gallus domesticus. As you may know, the ancestral species of the domestic chicken is the Red jungle-fowl, from India and SE Asia. It may have occurred further West than now, historically (at the time of domestication). Gallus lafayetii is closely related to Gallus gallus, both species having a similar appearance in male and female forms. The hen is a drab looking, elongate bird, more dissimilar to domestic hens than the rooster (given that domestic hens are larger, selectively bred for their body/egg size). The call of Gallus lafayetii is distinctive compared to Gallus gallus, the latter having a call that sounds like a wild form of a farm chicken, however, the Sri Lankan form does produce a respectable, crowing, kruk-kruk (described by earlier writers as "George joyce"), that is somewhat distinctive from Gallus gallus' "cock-a-doodle-doo". Males and females live in close proximity and thy often form small flocks. Chicks look more like the hen. Hens also have yellow eyes compared to cocks that have white eyes. They are typically very shy but have very chicken behaviour. Very attractive birds, these were filmed at Sinharaja forest and given the rooster was watching me, it remained wary. The squirrel in some of the images is a Layard's squirrel. The female makes a few appearances.
I think the bloodline of this chicken is quite safe. It should first be pointed out that yes, this chicken does hybridise with the domestic, to produce viable young, however the junglefowl does retain a certain integrity with its call and habits and I doubt it's genetic identity is threatened that much. On the other hand, the bloodline of the red junglefowl is probably severely compromised in places, but this is not the red junglefowl.
Pothila 5 months ago