Is the Ibis the next Rainbow Lorikeet or Cane Toad?
The Rainbow Lorikeet (Trichoglossus haematodus) is regarded as either a pest of agriculture or an unwanted organism in New Zealand, Western Australia, Northern Territory, Queensland, the Australian Capital Territory, Victoria, Tasmania and South Australia. On the east coast it inhabits rainforests, coastal bush and woodland areas. In Western Australia, the Rainbow Lorikeet is a declared pest.
It appears that when they were first released in Perth, there were no fewer than 10 birds and no action was taken to remove them. The Rainbow Lorikeets became established as a feral species in Perth in the late 1960s, but it wasn’t until the 1980s the population began to expand rapidly.
The Department of Agriculture and Food (DAFWA) indicate that they are excessively noisy, damage fruit, foul outdoor areas and vehicles with their droppings and compete with other species, especially for nesting sites. DAFWA reports that they will feed on grapes, ?gs, pears, apricots, nectarines, loquats, mulberries, mangoes, passionfruit, cherries, apples, peaches, plums and guavas in Perth suburbs and are causing significant damage to table grapes in the Swan Valley and fruit crops in the hills orchards.
Had the relevant state government agencies dealt with this problem when we had a small number of birds, then the solution would have been relatively easy and inexpensive. It is probably true to say that we will never get rid of Rainbow Lorikeets in Perth, and as the problem continues to get worst, additional resources will need to be taken from other conservation programs and directed at reducing their numbers. Early action would have saved the people of Western Australia significant costs and a variety of negative impacts.
The same could also be said for the Cane Toad (Rhinella marina). We knew 30 years ago the Cane Toad would eventually get to Western Australia and would have a very significant impact on the native fauna in the Kimberley. In 2003, Graham contacted senior staff in the DAFWA and DPaW asking what action was being taken to stop Cane Toads from entering Western Australia. The DAFWA employee indicated that as they don’t impact on stock or crops then it was not its problem, and the DPaW employee indicated that as there was no solution DPaW was not going to do anything, as there was nothing it could do.
It was not until the Kununurra Community organised a two day workshop in May 2005 on stopping the Cane Toad, that the State Government and DPaW were forced to act. Multiple speakers at this workshop discussed potential solutions to the problem, talked about what had occurred in Queensland and the Northern Territory and the potential impact that Cane Toads would have on the Western Australian fauna. The Western Australian government eventually responded with a publicity campaign hoping to stop the early incursions into Western Australia and provided funds for organisations in Kununurra to collect and kill toads near the WA border with the Northern Territory. As was predicted at the workshop, unless there was a serious commitment to funding the appropriate research then Cane Toads would invade the Kimberley and possibly move south into the Pilbara.
Like the Rainbow Lorikeet, had an appropriate investment be made into research and appropriate plans put in place to stop the Cane Toad 20 years ago, then perhaps they would now not be in the Kimberley and about to invade the Pilbara.
Is the Australian White Ibis (Threskiornis molucca; also known as the Sacred Ibis or White Ibis) the next Rainbow Lorikeet or Cane Toad. The Australian White Ibis appears to have progressively moved south and into urban areas. For example, they were in low abundance in the Sydney area in the 1940s but their numbers increased in the 1950s (Martin et al. 2010), similarly the Ibis population grew rapidly on the Gold Coast in Queensland between 1995 and 1998. As an example, Martin et al. (2010) reported they increased from a peak of 4,200 in 2006 to 8,900 in 2008 in the Sydney urban area. Ibis are considered a pest species in urban areas along the east coast as they pose a threat to aircraft safety, scavenge food at waste-management facilities and compete with other native species for food and habitat (Martin et al. 2007). Across Australia they are often referred to as ‘bin chickens’ due to their propensity to occur in waste management and landfill areas.
Epstein et al. (2006) reported that the Australian White Ibis are hosts of zoonotic and livestock pathogens such as Salmonella spp., Newcastle disease virus, avian influenza virus, and flaviviruses in Australia, and there is a potential for these diseases to be transmitted to humans.
Ten years ago there were a few Australian White Ibis around wetlands in Perth and some areas in the south-west; however, we can never recall seeing them foraging in residential gardens in the suburbs, but this is now a common sight. Around swamps and wetlands Ibis feed mainly on aquatic invertebrates, but will also take frogs and small fish, and in the south-west they are known to feed on the dung beetle and its larvae.
In recent years we have seen a significant change with large numbers now foraging in land fill and rubbish tip sites. There is a large population of Australian White Ibis at the City of Stirling rubbish disposal site in Balcatta, the Southern Metropolitan Regional Council’s Regional Resource Recovery Centre in Canning Vale, and the Henderson Waste Recovery Centre in Cockburn to name but a few.
So are we going to do something about the problem now, or will we wait until they are totally out-of-hand and there is evidence of people getting sick due to diseases being transmitted by this species before something is done. Being a reasonably large bird that congregates at a few locations means that management can be effective and relatively cheap, but the costs and problems will only increase if we continue to procrastinate.
Has anyone else experienced large numbers of these birds causing problems around Perth?
Images – top and bottom: Ibis at waste management facilities
References
Epstein, J. H., J. McKee, P. Shaw, V. Hicks, G. Micalizzi, P. Daszak, A. M. Kilpatrick, and G. Kaufman. 2006. The Australian White Ibis (Threskiornis molucca) as a Reservoir of Zoonotic and Livestock Pathogens. EcoHealth 3:290-298.
Martin, J., K. French, and R. Major. 2010. Population and breeding trends of an urban coloniser: the Australian white ibis. Wildlife Research 37:230-239.
Martin, J. M., K. French, and R. E. Major. 2007. The pest status of Australian white ibis (Threskiornis molucca) in urban situations and the effectiveness of egg-oil in reproductive control. Wildlife Research 34:319.
Comments
One Response to “Is the Ibis the next Rainbow Lorikeet or Cane Toad?”
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Geez, I couldn’t disagree more. From an ecological perspective, these Ibis have moved to the Perth Metro area through natural means, I.e. migratory flight. Likely following landscape changes and perhaps loss of their more recent historical habitats. They are simply very well adapted to living in the environments humans have recently created (fragmented wetlands, irrigated lawns and parkland, waste disposal sites). If we apply the same logic (obvious size, causing mess, displacing Perth native birds) to one of our iconic species – the red tailed black cockatoo – would you still advocate for “active management”?
How many animal species are vectors for disease? Salmonella, avian influenza etc aren’t exactly very specific to the white Ibis. To me, it sounds like the reason you don’t like them is because they are very obvious and you associate them with rubbish and disease. Your rational for exterminating this species would not stack up if applied broadly to other Australian or exotic fauna. Perhaps instead of looking for an easy scapegoat (Australian White Ibis are often considered ugly and dirty due to their size and habit of scavenging, does this make them intrinsically bad?) consider what the real causes of your various problems are, they inevitably lead back to recent (last 100 years)human actions. Ibis are a symptom of human induced environmental changes, not the problem.
Cane Toads were introduced by humans, they are responsible for a small fraction of the loss of native animals that recent human actions have caused in northern Australia (there is also mounting evidence that many of our native animals are adapting to their presence and able to co-exist as well). They are also obvious and ugly. Still the impacts can hardly be compared with the Ibis.