Ticking Off Eagle Nests

The time of year for Wailitj / Wedge-tailed Eagle (Aquila audax) ringing is upon us again, with most nests having quite large eaglets that are the perfect age for fitting with colour rings. Having just returned from my arid zone eagle research site at Matuwa last week, I was ready to carry on 'eagling' in the Perth Hills over the weekend and visited an amazing eyrie to ring/band the chick with my beautiful friend Dani on Sunday morning.

This eaglet 6-week old eaglet's eyrie was framed beautifully by the nest tree's limbs.

The eagle nest was located high in a live but very old and partially hollow Powderbark (Eucalyptus accedens) tree, which made the climb a nerve-racking but spectacular experience. I scaled the main trunk using ropes, then tied a safety line around the huge limb that I followed out towards the nest, inching my way along and trying not to pay too much attention to the multiple entrances to its hollow cavities, all covered in chew-marks from prospecting activities by local parrots.

This Powderbark tree has been growing in the landscape for several centuries.

I reached the young Wedge-tail and admired his view across the beautifully forested surrounds, before lifting him gently into a handling bag and lowering him safely to the ground below. Dani took him into the shade where we both worked quietly to weigh, measure and fit the two types of rings/bands. Having the bird so close allowed me to notice a small Kangaroo Tick (Amblyomma triguttatum) at the edge of its eye.

A kangaroo tick is visible just below the eaglets brow, smaller than the ever-present bush fly in the centre.

While ticks are perfectly good climbers and probably capable of ascending into the canopy on their own, I suspect this parasite may have been transported into the eagles' eyrie 'on board' a Yonga / Western Grey Kangaroo (Macropus fuliginosus) joey, common food for eagles nesting in the Perth Hills. Once the joey had been eaten, the tick probably went crawling for an alternative host, with the eagle chick being the nearest new victim. I chose not to remove this parasite as I know that these animals do drop off eventually, and risking damage to such an important part of such a young bird's body was not worth it.

Ringing and processing complete, it was great to place the eaglet back on its lofty nest and take in more off the amazing view. Now onto the next nest!