Thursday, February 3, 2011

The Living Ghosts of Twitches Past

A pre-Christmas visit to Rottnest Island appeared to confirm the rumours were true – the Indian Peafowl control program may well have removed the last peahen from the island [1]. Long-time island residents confirmed that, to the best of their knowledge, the two adult male peacocks currently hanging around the Thompson Bay settlement are the last remnants of this historic population.

Peacock memories, Rottnest 1994.......OK, laugh at the hair if you must!

According to Saunders & de Rebeira’s ‘Birds of Rottnest Island’ (1993), this famous feral population was established sometime between 1910 and 1915, and quickly became naturalised. In the early days the birds ranged further west around the salt lakes, but in recent decades their stronghold has been the Melaleuca woodlands around the Kingstown Barracks. Increasingly though, the population had become ‘urbanised’ and taken to foraging for scraps around the Thompson Bay settlement, causing destruction of gardens and scaring small children with food. It would be fair to say the current territorial range of the two remaining peacocks is centred on the Rottnest Bakery! (which, like the peafowl population, now trades somewhat on past glories).  Since 1992, the Rottnest Island Authority has been reducing the population by trapping and removing peahen and chicks from the settlement area, and this seems to have reached its inevitable conclusion in late 2009 [1].

This will no doubt pose many conundrums to twitchers and purist listers – do they tick these undoubtedly ‘wild’-born peacocks, or are they deemed un-tickable as ‘living ghosts’ of a now-extinct feral colony? Even if an unlikely guerrilla female is spotted, is this population now too small and controlled to be self-sustaining? If the RIA change their mind and reintroduce peahen - after all, peacocks do feature prominently on their promotional website! - how long before they can be ticked again?

Contrast this situation with the equally-famous Mute Swans of Northam, which are also now effectively ‘un-tickable’ due to the concerted efforts of the Shire and its ‘Swan Warden’ to artificially preserve this dwindling colony. Though this colony dates back to the early 1900s, breeding success has dwindled in recent decades and is now supported through a fenced nesting area and a “new breeding program” [2] – read imported birds. Though the swans are again freely gracing the Avon after a prolonged absence, it’s anyone guess whether these are imported newcomers or inbred, sterile originals. When inevitably ruled an unsustainable feral population (though by whom, well, that’s a topic for a much longer and more contentious blog!), Northam’s Mute Swans may end up protected by WA State law, despite the official Australian bird list denying their very existence – another living ghost of twitches past.

Mute Swan at Northam.

Incidentally, that other famous feral on Rotto, the Common Pheasant, is as common as ever. Being mostly granivorous, they tend to stay near fresh water sources at the eastern end of the island. Heath in the Kingston Barracks / Bickley Swamp area, the cemetery, the western end of the golf course, or around the northern and western shores of Lake Baghdad are good places to try at the moment, but they are usually not difficult to find. The RIA estimates their population at around 200 birds, and though not yet controlling them, is “investigating the impacts of exotic species on natural flora and fauna” [1] – pheasants have been observed eating native snails on the island [3] – so watch this space.

Male Common Pheasant on Rottnest Island.

[3] Farmer W.A. (1961) Pheasants feeding on snails at Rottnest I. Western Australian Naturalist 8(2), 50-51.

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