Although influenced by several different cultures, Javanese hold roots in East Indian mythology and lore. The Iban of Borneo, who migrated from China to Indonesia, believe Sengalang Burong is the origin of creation and lives throughout the forests of Java. Accepted translation of Sengalang Burong in English means the bird chief or bird god, aptly fitting Iban religious beliefs as all birds being the manifestation of the spirit son of Burong. Further tracing the lore we find that Sengalang himself manifests as a white and brown hawk. Interestingly, Javanese Wood Owls currently living on the island are also white and brown, with hawk-like features.
In the late 1920's naturalist Dr. Ernest Bartels entered part of the forest locals claimed he should not go based on spiritual beliefs. He ended up having a close encounter with a giant bird as it flew over his head and later referenced what happened, calling this bird an Ahool, after the unique howling sound it let out while passing by. Ivan Sanderson confirmed later, by Bartels' account and an encounter of his own, that it must be a new species. Both visitors claimed local residents of the island knew of very large flying creatures in the rain forest, but generally elected to stay away themselves. Since large species of Earless owls exist in the Javanese forest, it both aids and hinders Bartels' case at the same time.
It's quite possible an unknown subspecies exists with gray fur and very rarely witnessed, and on the other hand, researchers might believe based on details of Bartels' encounters that he simply confronted one of the Earless owl species; Possibly a specimen with melatonin deficiency causing feathers to lose pigment. A plausible explanation for both Ernest and Ivan's events could very well be mistaken identity, and a very close encounter as described might result in the Ahool-type noise heard due to a Doppler effect from a territorial protective Earless owl. There is of course a third possibility, that Ernest and Ivan may have encountered the bird god Sengalang Burong, and the very reason locals would not enter those parts of the forest.
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