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Tasmania |
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The state of Tasmania covers an area of over 68,000 square kilometres (about a quarter of the area of New Zealand).
Tasmania contains Australia’s largest tracts of cool temperate rainforest, which grows mainly in the north west and west of the island, and in patches in the north east highlands. Many species of this flora are derived from Gondwana, as is the flora of New Zealand. The dominant species is Beech (Nothofagus cunninghamii), and includes some other species similar to those occurring in New Zealand such as Manuka (Leptospermum scoparium) and Tree ferns (Dicksonia species). The east of Tasmania is largely covered by dry sclerophyll eucalypt forest, although substantial parts of the lowland areas have been greatly modified for agriculture.
Nectar eating Parrots in Tasmania
No nectar eating parrots live in the cool temperate rainforests of western Tasmania.
Only two nectar eating parrots- the Swift Parrot and the Musk Lorikeet - live in the
sclerophyll forest of eastern Tasmania.
The Swift Parrot visits Tasmania to feed and breed in Bluegum trees in the east, including wet eucalpyt forest, but does not breed in the rain forest. It overwinters on the Australian mainland where it feeds on winter flowering eucalypts.
The Musk Lorikeet (possibly a Tasmanian subspecies) is a permanent resident of Tasmania, breeding in the dry sclerophyll forest of the east. It does not occur in wetter sclerophyll forests, or in the cool temperate rain forest due to lack of suitable nectar and pollen resource. The Musk Lorikeet has similar food requirements to the Rainbow Lorikeet, but occurs only in the cooler climates of south-east Australia.
The Little Lorikeet and the Purple Crowned Lorikeet both live on the coast of Victoria close to Tasmania. The Little Lorikeet has been recorded a few times in Tasmania, but has never bred there. The Purple Crowned Lorikeet appears to have been never recorded in Tasmania (HANZAB).
Competition with other Nectar Eating Species
The two nectar eating species of parrot in Tasmania, the Musk Lorikeet and the Swift Parrot, within their range, co-exist in mutual competition with the following parrots and honeyeaters, all of which overlap in food requirements (nectar) or nest sites (suitable nest holes) with them.
Parrots: Resource Overlap
6 Species other parrot nest sites
Honeyeaters: Resource
Overlap
Yellow Wattlebird nectar
Little Wattlebird
nectar
Crescent Honeyeater nectar
New Holland Honeyeater nectar
Tawny-crowned Honeyeater nectar
Eastern Spinebill
nectar
Raymond Brereton, an officer of the Tasmanian Parks and Wildlife Service considers that the finer bills of honeyeaters enables them to access a far greater variety of nectar bearing flowers than lorikeets. He is also considers from observations in Victoria that where lorikeets and honeyeaters have increased in urban areas, the smaller honeyeaters and other small insectivorous birds are subject to increased competition from the larger more aggressive honeyeaters, not from lorikeets.
In Tasmania, the Swift Parrot and the Musk Lorikeet do not compete with the following
four Honeyeaters, three of which have from long adaptation to Tasmania’s forests
become almost exclusively insectivorous:
Noisy Miner (range eastern Tasmania, south east Australia)
Strong-billed Honeyeater (range Tasmania, Bass Strait Islands only)
Black-headed Honeyeater (range Tasmania, Bass Strait Islands only)
Yellow-throated Honeyeater (range Tasmania, Bass Strait Islands only)
Migratory Parrot Species In Tasmania
Two species of small parrot, the Orange-bellied Parrot and the Swift Parrot, regularly migrate between Tasmania and the Australian mainland. The Orange-bellied Parrot uses King Island in the Bass Straight as a staging point, while the Swift Parrot flies directly between the mainland and Tasmania. Both birds are smaller than the Rainbow Lorikeet, which may be expected to fly faster and further.
The Rainbow Lorikeet In Tasmania
Up to 1998, Rainbow Lorikeets (and Little Lorikeets and Purple Crowned Lorikeets) had never managed to colonise Tasmania. Since small parrots visit Tasmania each year, the Rainbow Lorikeet must have had many chances in the past. Occasional sightings (3 since 1960) have been made indicating that Rainbow Lorikeets have managed to make the trip across from the mainland, but no breeding has ever been recorded.
Since November 1998 a group of 12 birds presumably from the mainland has been seen at Ulverstone on the north-west coast of Tasmania, feeding in urban areas on non-native flowering eucalypts. Outside this urban area, the north coast of Tasmania is a mix of wet and dry scerophyll forest. Officers of the Parks and Wildlife Service consider they are unlikely to become established outside the urban area due to the limited sources of food all year round.
A small population of Rainbow Lorikeets has also been regularly recorded on King Island over the last 6 months. They were observed feeding on flowering blue gum which flowers from September through to January. These birds have almost certainly come from the mainland and may be part of the same movement which resulted in birds being recorded in Ulverstone.
A small population of about 6 Rainbow Lorikeets is currently living in a suburb south of Hobart, presumably from an aviary release, since no lorikeets have ever been recorded so far south. Neither the population or range has expanded in 3 years, indicating that the birds have failed to breed.
The officers of the Tasmanian Parks and Wildlife Service consider that the Rainbow Lorikeet may become established in Tasmania given the recent records in northern Tasmania and on King Island. However, they consider it likely that they will only become established in urban areas as they have done on the mainland where there is sufficient food resources available in gardens and parks, through the planting of native, but not necessarily endemic flowering shrubs and trees, particularly through the winter months. Given their present knowledge, they consider that the Rainbow Lorikeet will not threaten native populations of large or smaller honeyeaters, the musk lorikeet, or the endangered swift Parrot, particularly in their natural forested habitats.
The officers of the Tasmanian Parks and Wildlife Service consider the likelihood of Rainbow Lorikeets colonising the New Zealand bush no different to its record in Tasmania.
STATE OF TASMANIA INFORMATION SOURCES
Parks and Wildlife Service
Raymond Brereton,
Manager Swift Parrot Recovery Program, phone 00613-6233-3117
fax 00613-6233-3477
Peter Brown, Manager Threatened Species Program phone 00613-6233-6139 fax
00613-6233-3477
In March, I called Raymond Brereton to enquire into the historical status and breeding
possibilities of RBLs in Tasmania.
Raymond Brereton said in the phone conversation:
That neither Rainbow Lorikeets or any other lorikeet live in Western Tasmania. That
Musk lorikeets and the Swift Parrot a small parrot which has adapted for nectar feeding
live in the sclerophyll bush of Eastern Tasmania. That a probable aviary release of 6
Rainbow Lorikeets has lived in a new suburb south of Hobart for some 5 years without
expanding their population or range. That in his opinion Rainbow Lorikeets cannot live in
the cool temperate rainforest of west Tasmania although a few species of honey eater live
there successfully. That he will talk with Peter Brown and send a short written report.
Following this conversation, I sent a written enquiry on 11 March (enclosed).
Raymond Brereton sent a reply (enclosed) by email on the 22 March, detailing the two nectivorous parrots in Tasmania, and the likelihood of Rainbow Lorikeets living in wet forests.
On May 11, I called Raymond Brereton to ask him to check my summary, and to enquire
into the honey-eaters resident in Tasmania.
Raymond Brereton said in the phone conversation:
That several Tasmanian Honey-eaters have become insectivorous in their habits, and
behave more like Tree-creepers, hopping around and underneath branches collecting insects.
That when flowers were available, the fine bills of the honeyeaters enable to them to
access a far greater variety of the smaller nectar bearing flowers than lorikeets.
On 13 May I sent an email asking him to include a report on concerns about RBLs in
Tasmania.
On 19 May Raymond Brereton said:
That 4 species of Tasmanian Honeyeater were almost exclusively insectivorous (Noisy
Miner, Strong Billed ,Black Headed, and Yellow Throated Honeyeaters) That he had done some
work on the mainland with 4 nectivarous parrots foraging together in one small area, and
that there did not appear to be a problem through competition. That lorikeets and
honeyeaters had expanded their range through the increased planting of flowering trees in
urban areas. That there has been a possible decrease in smaller insectivorous birds
(including insectivorous honeyeaters) due to increased competition from larger and more
aggressive honeyeaters such as the New Holland Honeyeater, but not from competition from
lorikeets. That he knew of one case in Victoria where larger honeyeaters had to be
controlled to protect a remnant population of 50 smaller honeyeaters and that he would
send some contacts for this information. That my description of a Tui driving every other
bird out of a fruiting or flowering tree is similar to Wattle Bird behaviour. That Wattle
Birds and Lorikeets coexist without any noticeable effects of competition. That smaller
nectivarous birds such as Eastern Spinebill and Silver Eye have a difficult time with the
increase of the larger New Holland Honeyeaters. That the worst enemy of the smaller
honeyeaters is the increasing number of larger and more aggressive honeyeaters. That this
behaviour had been only observed in urban situations with the population expansion of
lorikeets and honeyeaters, due to the unnatural abundance of nectar bearing species
planted in gardens and parks.
That the RBLs recorded from King Island over the last 6 to 8 months were almost certainly part of the small flock which had arrived at Ulverstone. That the Rainbows on King Island would have survived on flowering Blue Gum through the summer months but that they would now need winter flowering trees such as Banksias to survive through the winter.
That RBLs were not a considered a threat to the native bird populations of Tasmania,
that the evidence they had from other parts of the mainland was that they would not become
an issue, that they really were an urban phenomenon, due to altered and unnatural
environments.
Raymond Brereton sent an email (enclosed) later on the 22 May, correcting my earlier
notes, and provided a summary.
In a phone call to Raymond Breton on 23 May I asked if he would have Peter Brown check the text report for accuracy, and also asked for contacts on Lorikeet/Honeyeater interaction. He replied by email (enclosed) on the 24 May, providing contacts in Victoria for further research into interactions between Lorikeets and Honeyeaters.
SUPPORTING DOCUMENTS
Fax to R Brereton, 11 March 1999
Email
from R Brereton, 22 March 1999
Fax to R Brereton, 11 May 1999
Email to R Brereton, 13 May 1999
Email from R Brereton, 19 May 1999 )
Fax to R Brereton, 24 May 1999
Email from R Brereton, 24 May 1999
OTHER REFERENCES
Forshaw,
J.M., Australian Parrots, Lansdowne Press 1981
Pizzey, G., A Field Guide to the Birds of Australia, Collins 1982
HANZAB, Higgins, P.J., Handbook of Australian, NZ, and Antarctic Birds Vol 4, Oxford
1999