A sad end

After thousands of kilometres flown on migration flights over four years, one of the GPS-tagged Little Eagles, Y2, has been found dead. This was her flying in february 2021, two years after being fitted with a tag.

This was how Y2 was found in september this year. The exact cause of death cannot be proved, however the evidence points to her having been at least partially eaten by a feral cat if not killed by a cat. Her colour band number Y2 can be clearly read, and her GPS-tag was still attached and signalling. That was how her location was known and indicated that something was wrong as she had not been moving.

Her body was found underneath bracken, below trees where she had been roosting frequently after her return migration flight to her summer home range. 

Her tail was lying a few metres from her body, the cut off ends to the bases of the feathers indicate that they had been bitten off by a predator or scavanger, possibly a fox or a cat. A bird would not cut off the feathers, they pluck them. The head and a leg were missing, and the body had been chewed rather than crunched like a fox would do. And the body had been eaten from the back and rear, another feature of a cat kill.

Her wing feathers had also been bitten off, rather than plucked.

Y2 was fitted with her tag in November 2019 and she died in September 2023, only 470m from where she was tagged. Meanwhile, in between, she had made four migratory flights to Cape York, to the exact same area, and back to the same summer home range area in the ACT. See more details of her movements in a previous post on this webpage on 13 May 2022. She would leave in March/April each year and return in late August/September. Yet, she was an adult bird when tagged, so how many trips and kilometres did she fly in her whole life. 

A bird to remember.

Wildfire smoke reduces Little Eagle flight activity

D2, one of the featured birds, is seen here upon his release after being fitted with a GPS-transmitter.

A new paper from the Little Eagle Research Group has been published online in Emu - Austral Ornithology - 

Wildfire smoke reduces Little Eagle (Hieraaetus morphnoides) flight activity.

Stuart Rae, Renee Brawata, Claire Wimpenny, Micah Davies and Jaimie Hopkins 

see the article here 

Abstract

There have been few empirical studies of the sensitivity of birds to the effect of air pollutants. In late 2019 and early 2020 the Australian Capital Territory (ACT) and much of south-eastern Australia were affected by extreme wildfire events and smoke extended to surrounding areas. Prior to this event, GPS transmitters had been fitted to a sample of Little Eagles Hieraaetus morphnoides in the ACT as part of a study of their movement behaviour. Three of these birds carried transmitters in the breeding season during the fires and in the previous breeding season. This offered opportunistic analysis of data from both periods to test for effects of smoke on the birds’ flight behaviour. The effects of particulate matter in the air of ≤2.5 microns in diameter (PM2.5) and covariates on flight status were investigated with a binomial generalised linear model with logistic link. The birds were more likely to fly when there were low levels of PM2.5 and the odds of flying decreased as density of PM2.5 increased at a rate of 0.202% per ug/m3. None of the sample birds died during or after smoke exposure, although their respiratory system might have been affected.

Z5, one of the other subject birds, prior to release after being fitted with a transmitter.