The natural range of rainbow lorikeets is broad, including the northern coasts of Australia, parts of eastern Australia and South Australia, Papua New Guinea, New Caledonia, Solomon Islands, Vanuatu, Timor-Leste, and Indonesia. They have been introduced to Perth, Hong Kong, Singapore, and New Zealand, and a few vagrants have found their way to Tasmania.
As cities and suburbs grow, bird populations have winners and losers. Some birds struggle with habitat loss, while others adapt readily to urban development and a year-round food supply from suburban gardens. Rainbow lorikeets are one of the big winners. Loud, aggressive, and traveling together in large flocks, they compete for available food and nesting trees, driving out local birds. They are prodigious breeders, producing up to three broods a season. Efficient eaters, their tongues are like bristle brushes, well adapted to reach deep within native flowers to extract their preferred food: nectar and pollen. They also eat insects and seeds and they LOVE fruit. And therein lies a problem.
The rainbow lorikeet is a menace to fruit. In Perth’s suburbs in Western Australia, lorikeets feed on figs, pears, apricots, nectarines, loquats, mulberries, mangoes, passionfruit, cherries, apples, peaches, plums, and guavas. In commercial fruit-growing areas, they have decimated table grapes and a range of other fruits. The bird is considered either an agricultural pest or an unwanted organism in New Zealand, Western Australia, Northern Territory, Queensland, the Australian Capital Territory, Victoria, South Australia, and Tasmania.
New Zealand’s problems with lorikeets began in Auckland in the 1990s when a few dozen birds were deliberately (and illegally) released into the wild. Ten years later, the population had grown to 200 birds. They were successfully removed, mainly by live capture, by 2002.
Tasmania is especially concerned by new sightings and the risk to its fruit-growing industry. Rainbow lorikeets also pose a threat to native Tasmanian parrots as they compete for food and resources. The birds carry Psittacine beak and feather disease, further threatening native parrots. The Tasmanian Government noted the cautionary example of Western Australia. Fewer than 10 rainbow lorikeets had been introduced in the 1960s. By 2006, the population was estimated to be as many as 20,000 birds. Seeking to avoid Western Australia’s fate, Tasmania is considering eradication measures to keep rainbow lorikeets from getting fully established.
What do rainbow lorikeets mean for Canberra? The Canberra Ornithologists Group observed that the resident population of rainbow lorikeets is gradually spreading south. Reported sightings climbed to 7.6%, which is 17% higher than last year and three times the 30-year average. Naturalist Ian Fraser commented in an article that the numbers of rainbow lorikeets (along with another parrot, the little corella) are steadily increasing: "Most people don't notice it yet, they're still relatively restricted, but they're starting to breed in the nature reserves. They're going to be all over Canberra in the next couple of decades I think."
Birders have begun observing the pressure on local birds. The photo below shows a lorikeet driving away a pair of eastern rosellas from their nesting hollow.
I imagine my neighbor’s small fruit orchard will suffer along with the local birds. And did I mention how noisy rainbow lorikeets are? While feeding flocks are generally fewer than 50 birds, they can contain more than 1,000. Here’s what a flock of 30 sounds like. Now imagine hundreds in a swarm.