what is its behaviour?
Generally territorial and monogamous.
White-bellied sea eagle
The white-bellied sea eagle is generally territorial; some birds form permanent pairs that inhabit territories throughout the year, while others are nomadic. The species is monogamous,
what is white-bellied sea eagle? A large diurnal  bird of prey.
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White-bellied sea eagle [SEP] Behaviour
The white-bellied sea eagle is generally territorial; some birds form permanent pairs that inhabit territories throughout the year, while others are nomadic. The species is monogamous, with pairs remaining together until one bird dies, after which the surviving bird quickly seeks a new mate. This can lead to some nest sites being continuously occupied for many years (one site in Mallacoota was occupied for over fifty years). Immature birds are generally dispersive, with many moving over away from the area they were raised. One juvenile raised in Cowell, South Australia was reported away at Fraser Island in Queensland. A study of the species in Jervis Bay showed increases in the numbers of immature and subadult birds in autumn, although it was unclear whether these were locally fledged or (as was considered more likely) an influx of young birds born and raised elsewhere in Australia.