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South Australia |
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The State of South Australia covers an area of 980,000 square kilometres (an area just
under four times that of New Zealand).
The Rainbow lorikeet (Trichoglossus haemotodus moluccanus) occurs only in the extreme
south east of the state.
South Australia produces a wide range of tree and vine fruit similar to that grown in
New Zealand, and has well established crops (in approximate order of importance) of wine
and table grapes, apples, cherries, apricots, pears, nashi, peaches, nectarines, plums,
avocado, persimmons, with olives becoming important. Many areas have now been under
permanent cultivation for well over 100 years.
The worst bird pest of grapes are Starlings and Silver eyes, followed by Rosellas and
Regent Parrots, Blackbirds, Sparrows and Red Wattle Birds.
The worst pest of cherries is the Rosella, which eats the flower buds throughout the
growing season. When the fruit ripens the Rosellas are joined by Silver Eyes, Red Wattle
birds, Black birds, Starlings, and a number of Honey Eaters, Crow and others. In some
years due to lack of their normal food in the bush, Red Wattle Birds can be the most
significant pest. Crop losses in cherries in the Adelaide Hills area can be very high with
figures quoted from individual farmers of 30% minimum loss with a full bird scaring
program. Cherry growers are now starting to use nets on newer dwarf varieties of cherries.
Soft fruit are damaged by a range of birds including Silver Eyes and Sparrows, Red
Wattle birds, Musk Lorikeets, Black birds, Starlings, and Crows.
Damage to Olives is mainly caused by Starlings, then Blackbirds, and a number of others.
Crop damage reported by apple, pear, and nashi growers in the Lenswood area of the Adelaide Hills (which is more affected by bird damage than most) averages about 5% for all three crops. The major pest of apples in this area are Rosellas, which not only eat the flesh but also the seeds particularly of new varieties such as Abbas, which has double the usual number of pips. Rosellas are present all through the season and cause a continuous loss. Total bird damage to traditional varieties such as Jonathon, Red and Golden Delicious, and the less sweet Granny Smith is about 1%, almost entirely from Rosellas. After Rosellas, the next worst damage to apples is caused by Musk Lorikeets. Musk lorikeets appear usually in flocks in April, and cause more damage to sweeter mid and late harvest apple varieties, such as Fuji, Gala, and Pink Lady. One large grower quoted Fuji losses of 5% to a combination of Rosellas and Musk Lorikeets, with sunburn losses of 10%. Damage to all varieties of apples from Rainbow Lorikeets and White and Black Cockatoos is much less than Musk Lorikeets.
Musk lorikeets are reported as causing the majority of damage to nashi and pears, again with much less damage from Rainbow Lorikeets and White and Black Cockatoos. Rosellas are reported to cause negligible damage to pears and nashi.
Growers interviewed reported Rainbow Lorikeets as causing a maximum of one third of the
damage (in apples), down to one eighth of the damage (in nashi and pears) to that caused
by Musk Lorikeets. Some growers reported negligible damage from Rainbow Lorikeets.
Rainbow lorikeet damage to Pome fruit in the (worst hit) Lenswood area alone is probably
less than 1% for pears and nashi, and a maximum of 1 or 2% for late harvest, sweet apples.
Lorikeet damage is negligible for early apples. In all cases this damage is small compared
to Musk Lorikeets, and Rosella damage greatly exceeds that caused by both Lorikeets.
Damage by native bird species varies greatly with the availability of bush food, with damage higher about one year in three. Damage is also higher in smaller and in isolated orchards particularly those close to bush reserves. A Fuji crop grown in an isolated orchard close to bush reserves suffered 20% loss to Rosellas and Musk Lorikeets, but negligible damage from Rainbow Lorikeets.
Competition with other Species
The range of the Rainbow Lorikeet in South Australia is limited to the south east corner. In this range the Rainbow Lorikeet co-exists in mutual competition with the following parrots and honeyeaters, all of which overlap in resource requirements either of food (nectar and pollen) or nest sites (suitable nest holes) with it:
Parrots:
Resource Overlap
3 Species Lorikeet nectar,
pollen, nest sites
1 Species Swift Parrot nectar, nest sites
25 Species other Parrot nest sites
Honeyeaters:
Resource Overlap
2 Species Wattlebird nectar
1 Species Friar Bird nectar
3 Species Miner Bird nectar
21 Species Honeyeater nectar
The recent decades have seen a marked increase in the number of birds around the Adelaide Hills, even though most of the area has been growing fruit since the last century. Thirty years ago few people remember seeing Cockatoos, Galahs, Little and Long Billed Corellas, and lorikeets. The larger parrots have increased continuously over this period. In the last ten years, the lorikeets have grown in population, appearing in areas they were never seen before, with one apple grower saying the peak occurred 5 years ago. The increase in lorikeets seems to have been paralleled by an increase in the larger honeyeaters such as Red Wattlebirds, and an apparent decrease in the smaller honeyeaters, possibly due to competition from the larger honeyeaters.
A number of reasons for this expansion were suggested such as climate, land clearing and planting of more and new crops, bush regeneration etc. The population expansion has been particularly noticeable in the city of Adelaide, and it is likely that this garden city which has seen an increased planting of flowering trees may be providing more food for honeyeaters and lorikeets. At the same time the larger parrots such as Cockatoos, Galahs and Corellas have also increased their populations in the Adelaide urban areas.
No references could be found that interspecific competition between Rainbow Lorikeets and any other species for food or nest sites is anything other than normal.
STATE OF SOUTH AUSTRALIA INFORMATION SOURCES
Primary Industries and Resources South Australia
Animal and Plant Control Commission
Peter Bird, phone 00618-8303-9500, fax 00618-8303-9555
Ron Sinclair, phone
I contacted these officers to clarify claims made in the Rainbow Lorikeet Technical Information Media Package published by the Department of Conservation about February 1999, that Rainbow Lorikeets were a significant pest to soft fruit in Adelaide.
I sent a fax (enclosed ) to Peter Bird on 31 March 1999.
Peter Bird replied by letter (enclosed) giving some data on bird damage.
On 12 May I called Peter Bird to get a closer idea of damage in fruit crops.
Peter Bird said:
That the most important fruit crops in South Australia are wine and table grapes,
followed by Pome fruit and cherries, with newer crops such as olives now becoming
important. That the worst pests of both table and wine grapes are Starlings and Silver
eyes, followed by Rosellas and Regent Parrots, Blackbirds, Sparrows and Red Wattle birds.
The worst pests of the cherry crop are Rosellas which eat the buds, followed by Silver
Eyes, Red Wattle birds, Blackbirds, and a number of Honey Eaters, Crows etc. on the ripe
fruit. That there is an increasing use of nets where newer dwarf cherry varieties are
planted, but are disappointed with large crops of cherries too small to market. That the
worst pest of Olives is the introduced Starling. That in Adelaide City itself, Blackbirds,
Turtle doves and Silver eyes were a nuisance. That the worst pests of POME fruit in the
Adelaide Hills are Rosellas which tear apples apart to eat the seeds, followed by the Musk
lorikeet, then fewer Rainbow Lorikeets. That Musk lorikeets can be seen in flocks of 20 to
30, but Rainbow Lorikeets in smaller flocks of 8-10, max. 15. That Ron Sinclair could give
more information of the damage in the Lenswood Pome fruit area which was particularly
badly affected by bird damage.
On 19 May I called Ron Sinclair for more information.
Ron Sinclair said:
Total Pome losses from all birds can be from 5-10%, with some specific varieties
reaching up to 30% losses. The Abbas apple in particular, a new early ripening variety on
the market was subject to much more damage from Rosellas due to the double pip count, the
Rosellas getting twice the pips for the same effort. That areas such as Ashbourne and
Lenswood were the worst problem areas That lorikeets and other birds had been increasing
in the area in the last ten years probably due to the increased planting of flowering
trees. That honeyeater populations had been decreasing. That Silver eyes in cherries and
grapes were more of a problem than growers realised due to not noticing the birds because
of the cryptic colouring. Silver eyes with Sparrows were the major pest of apricots, with
Sparrows particularly a pest in dried apricots.
In a later conversation that day Ron Sinclair said:
That it was true that the larger honey eaters such as Red Wattle birds were increasing,
and it was possible that the decline of the smaller honeyeaters could be due to increased
competition from the larger honeyeaters. That there had been a general increase in many
bird populations. That as well as Lorikeets, Galahs, Cockatoos, Corellas and Long Beak
Corellas were not present in the same numbers 30 years ago, and had increased. That this
may be due to a change in Mallee resource, maybe climate change, bush regeneration in some
areas, land clearing in others, and an increase in fruit crop planting, and a change in
fruit varieties. That the Adelaide Hills fruit growing area had plenty of regenerating
native bush areas which provided a local reservoir for birds, that the birds were probably
resident in those bush areas, and did not fly in from long distances. That the bird
population of Adelaide City itself had greatly increased, and that this was probably
because it was a heavily planted with trees, and there had been further massive planting
of flowering trees to attract birds. That the RBLs were not really a problem in the city.
That a few individual people had problems with soft fruits being eaten in back yard
gardens, but that was all. That he often sprays the hose in his own garden in summertime
for the Rainbows- several hundred of them would come down to bathe in the spray- it was
quite a sight.
Mt Lofty Ranges Animal and Plant Control Board
Christine Carter, Secretary, Phone 00618-8391-2244, Home 00618-8389-1115, fax
00618-8391-0179
David Stevenson, Authorised Officer, Phone 00618-8391-2244, fax 00618-8391-0179
I called Christine Carter in March to ask if she knew of Rainbow Lorikeets as a problem in the Mt Lofty area.
Christine Carter said:
That she hadn’t heard that Rainbow Lorikeets were a problem. That birds were not
their area of responsibility but they handled all sorts of pest problems and she had never
had heard of one for Rainbow Lorikeets. That she is close to the major apple and pear
growing district of Lenswood, which is only 10KM away, and that if there was problem she
would have heard about it. That I should contact the Apple and Pear Growers Association to
check.
Apple and Pear Growers Association
Trevor Ranford, General Manager, phone 00618-8349-5073
I called Trevor Ranford in March seeking information on damage to POME fruits in South Australia.
Trevor Ranford said in the phone conversation:
That the Rosella was the worst pest of POME fruits. That the Musk Lorikeet was
increasing in numbers, with the Rainbow Lorikeets less of a problem than the Musk. Black
cockatoos were a problem .That it was very difficult to estimate level of damage. That the
Lenswood fruit growing area is surrounded by native bush and parks, and that the birds
would come in from those areas in the dry season when other food was short, and then
caused more damage .
In a later conversation, Trevor Ranford said:
That the Lenswood growers listed in the Yellow Pages would be able to give me damage
figures- that they would have the best idea. That all the growers were within 10Km of
Lenswood, except for the Coromandel Valley and Magerey and Sons could give me the best
idea of that area.
POME Fruit Growers, South Australia
With the help of Trevor Ranford, and the Yellow pages (enclosed) I conducted a number
of interviews by phone with growers in the Lenswood area and one in the Coromandel Valley.
Copies of these questionnaires are enclosed, with names and telephone numbers.
(Survey not complete at 27 July 1999)
SUPPORTING DOCUMENTS
Fax to P Bird, March 31 1999
Letter from P Bird, 1 April 1999
Apple and Pear Growers, SA Yellow Pages
Fruit damage questionaires
Forshaw,
J.M., Australian Parrots, Lansdowne Press 1981
Pizzey, G., A Field Guide to the Birds of Australia, Collins 1982
HANZAB, Handbook of Australian, NZ, and Antarctic Birds Vol 4, Oxford 1999