Little Eagle Migration News
On this World Migratory Bird Day we would like to
share an insight gained from the tracking study of Little Eagles that breed in
the Australian Capital Territory area.
Part of the Little Eagle Research Group’s aims is to
study the birds’ movement ecology. This has been done by fitting a sample of
birds with GPS-tracking devices. The study is not yet complete, all the data
have not yet been retrieved as there are still birds carrying them. However,
preliminary data show that several of the Little Eagles have returned to the same
overwintering areas they went to on migration in previous years. Here we give
one example, that of a female, Y2, whose migration was featured on this
website on 20 September 2020.
This is Y2, the adult female Little Eagle who has repeatedly travelled to the same part of Cape York on migration. She is seen here hunting from
a perch in a tree on the edge of the southern suburbs of the ACT. This
photograph was taken between her journeys
The previous report showed a map of her route north to
and south back from Cape York over the winter of 2020.
A copy of Y2’s route migration in 2020 as previously
shown.
In winter 2021, Y2 followed a very similar route
north, and took more or less the same route south. In 2020, she flew farther to
the east on the return journey. She took 14 days for her flight on the 2020
southerly flight and 15 days in 2021, travelling at an average of 130 km per day
and roosting at night.
Y2’s return flight south in 2021.
The area in Cape York where Y2 has overwintered. The south-eastern edge of the Gulf of Carpentaria is in the top left of the image.
The zone in the above map that is marked in orange is where Y2 spent winter in 2020, 6388 km2. The zone marked in purple was where she spent her time in winter 2021, 5366 km2. The blue area is 82% of the 2021 area that was within the 2020 area, 4388 km2.
In the ACT, the main foods eaten by Little Eagles are
rabbits and birds, with a smaller proportion of lizards. There are no rabbits
in Cape York. The habitat in the wintering area is savannah where they probably
mostly hunt for birds, or lizards and small mammals.
The latest news as of this week: Y2 has flown north again to the same area for a third winter.
The route followed by by Y2 this year was similar to those in the previous two years.
In 2020 she left the ACT on 14 March and took 10 days to reach her overwintering area, in 2021 she left on 26 March and took 9 days. In 2022 she left on 16 April, and took longer, 18 days. It is possible that weather might influence the timing or the birds' migration and further analysis of this is ongoing.
World Migratory Bird Day is an annual awareness-raising campaign highlighting the need for the conservation of migratory birds and their habitats. It is a global outreach and is an effective tool to help raise global awareness of the threats faced by migratory birds, their ecological importance, and the need for international cooperation to conserve them. This is a United Nations Environment Programme.
