Report on the 2015 nesting of the White-bellied Sea-Eagles

There has been a Sea-Eagle nest in the Newington Nature Reserve at Sydney Olympic Park by the Parramatta River for many years, with a succession of eagle pairs renovating the nest in the breeding season. There are few early records of successful breeding however and several eagles have been found dead. Following the death of a pair of breeding eagles in 2004, necropsy and chemical analysis of tissues was undertaken in order to determine the cause of death. Further study was recommended. Their success or failure appears to be closely linked with environmental conditions, particularly the accumulated persistent organic pesticides in Homebush Bay and the Parramatta River.

As in previous years since 2009, the breeding relationships, behaviour and diet of the White- bellied Sea-Eagles were studied using video CCTV cameras and by limited physical observation during daylight hours, from the time of nest renovation to fledging. In early 2015 a new Research Proposal was submitted and all approvals gained.

In 2014, a new nest (Nest 3) was built in an Ironbark tree some 100 metres from the nest used in 2013 (Nest 2). However, after some apparent disturbance the eagles returned to Nest 2. In 2015, they began renovations on Nest 3 in May, bringing sticks to build up the rails, or edges, of the nest and fresh leaves to line it. As previously observed, both eagles assisted in the construction stage.

Over all these years of observations, though initially there was no night time footage, there seems to be a definite trend for delayed incubation between the first egg laid and the second. The time between laying of the two eggs varied from three to five days when we were able to observe the lay. Eagles may exhibit "obligate siblicide", in which the larger chick invariably kills its smaller sibling; we have not observed this in our study.

The first egg SE-15 was laid - 26 June 2015, 11:55pm.
The second egg SE-16 was laid - 30 June 2015, 05:43am.