Little lorikeet (Glossopsitta pusilla) - vulnerable species listing
The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the Little Lorikeet Glossopsitta pusilla (Shaw, 1790), as a VULNERABLE SPECIES in Part 1 of Schedule 2 of the Act. Listing of vulnerable species is provided for by Part 2 of the Act.
NSW Scientific Committee - final determination
The Scientific Committee has found that:
1. The Little Lorikeet Glossopsitta pusilla (Shaw, 1790) is an endemic Australian parrot measuring 16–19 cm in length and weighing approximately 40 g. It is the smallest of the Australian Lorikeets. The body is bright green in colour and the head is green with red forehead and throat patches that do not extend behind the eye. These features, in combination with the black beak and green underwing coverts which are visible in flight, allow the species to be distinguished from other small lorikeets. The Little Lorikeet is most likely to be confused with the Purple-crowned Lorikeet Glossopsitta porphyrocephala, which in addition to red underwing coverts, makes a distinctively lower-pitched and buzzing call in flight (Higgins 1999).
2. The distribution of the Little Lorikeet extends from just north of Cairns, around the east coast of Australia, to Adelaide. In New South Wales Little Lorikeets are distributed in forests and woodlands from the coast to the western slopes of the Great Dividing Range, extending westwards to the vicinity of Albury, Parkes, Dubbo and Narrabri (Barrett et al. 2003).
3. There is no evidence of regular migration, but Little Lorikeets are generally considered to be nomadic (Higgins 1999), with irregular large or small influxes of individuals occurring at any time of year, apparently related to food availability. However, long term investigation of the breeding population on the north-western slopes indicates that breeding birds are resident from April to December, and even during their non-resident period, they may return to the nest area for short periods if there is some tree-flowering in the vicinity (Courtney & Debus 2006).
4. Little Lorikeets mostly occur in dry, open eucalypt forests and woodlands. They have been recorded from both old-growth and logged forests in the eastern part of their range, and in remnant woodland patches and roadside vegetation on the western slopes. In south-east Queensland (Smyth et al. 2002), Little Lorikeets were more likely to occupy forest sites with relatively short to intermediate logging rotations (15–23 years) and sites that have had short intervals (2.5– 4 years) between fires.
5. Little Lorikeets are gregarious, usually foraging in small flocks, often with other species of lorikeet. They feed primarily on nectar and pollen in the tree canopy, particularly on profusely-flowering eucalypts, but also on a variety of other species including melaleucas and mistletoes. On the western slopes and tablelands White Box Eucalyptus albens and Yellow Box E. melliodora are particularly important food sources for pollen and nectar respectively (Courtney & Debus 2006). They are also reported as feeding on fruits, particularly those of mistletoes (Higgins 1999).
6. The breeding biology of Little Lorikeets is little known, except for long-term observations (43 years) on the north-western slopes by Courtney and Debus (2006). This work, consistent with anecdotal records from around the country, indicates that nest hollows are located at heights of between 2 m and 15 m, mostly in living, smooth-barked eucalypts, especially Manna Gum Eucalyptus viminalis, Blakely’s Red Gum E. blakelyi and Tumbledown Gum E. dealbata. Hollow openings are very small, approximately 3 cm in diameter, and are kept open by the activities of the occupants, which use their beaks to bite away living bark from around the opening. When nest hollows are deserted, e.g. after storm-damage to trees, hollows can close over within 14 months (Courtney & Debus 2006). Nest hollows are occasionally located in dead trees, but birds generally desert hollows within two years of tree death. Nest-hollows are used “traditionally”, with the same hollow known to be occupied for at least 29 years (not necessarily by the same individuals) (Courtney & Debus 2006). The breeding season extends from May to September (Higgins 1999) and, if eucalypt nectar and pollen are available throughout this period, two broods of fledglings can be raised in a season. Clutch size is three to five eggs (Higgins 1999) and broods of three and four young have been recorded, with a single fledgling recorded from one nest (Courtney & Debus 2006). No data are available on generation time in wild birds and the “low-reliability” estimate of two years (Garnett & Crowley 2000), for the ecologically-similar Swift Parrot Lathamus discolor would seem a poor surrogate, given that other lorikeet species are known to survive and potentially breed for 20 years (Rainbow Lorikeet Trichoglossus haematodus: ABBBS 2008). Little Lorikeets in captivity are known to breed at one year of age (G. Phipps, pers. comm; 2008; R. Webb pers. comm. 2008) and this suggests a minimum age for maturation in the wild of one year. A life span of 10 years in the wild is a reasonable estimate for a parrot of this size (W Boles, pers. comm. 2008). An approximation of generation time based on the age of maturity plus half of the length of the reproductive period of the life cycle (IUCN 2008) suggests a generation time of approximately five years.
7. Population trends in Little Lorikeets are uncertain, but recent evidence of declines has led to recommendations for an urgent Australia-wide review (Courtney & Debus 2006; Horton & Black 2006). Nationally, Little Lorikeets were recorded significantly more often in the New Atlas of Australian Birds (Barrett et al. 2003) than in the Atlas of Australian Birds (Blakers et al. 1984) suggesting an increase in the national population between 1977-81 and 1998-2002. In NSW the species has either not changed or increased in reporting rate between the two Atlases. However, Barrett et al. (2003) caution that the two atlases used different survey methods and that it is unwise to make strong inferences of numerical change from atlas data. In particular, itinerant non-breeding flocks may be sufficiently common to exaggerate actual population size, particularly if flock size has decreased (Courtney & Debus 2006). Little Lorikeets were very common on the NSW Central Coast from February to May 2003-05, feeding on flowering Blackbutt ( Eucalyptus pilularis) and Swamp Mahogany ( E. robusta) (A.K. Morris in litt. 2007). They were the third most abundant of 25 nectarivorous species recorded in the Capertee Valley in regular surveys conducted between 1994 and 1997 (French et. al 1993). Numbers of Little Lorikeets appear to have declined on the south-west slopes and south coast of NSW (R. Allen unpubl. data, cited in Courtney & Debus 2006), and on the north-west slopes of NSW (Courtney & Debus 2006). A decline in Little Lorikeets is well documented in South Australia (Blakers et al. 1984; Horton & Black 2006) where they are now seldom recorded, except in the south-east, despite once being a common breeding species in the Adelaide region (Horton & Black 2006). The species is currently listed in South Australia as Endangered under the National Parks and Wildlife Act 1972, but is not listed nationally or in any other state. Horton and Black (2006) caution that there are many examples of bird species that are threatened nationally whose initial decline was first apparent in South Australia.
8. Analysis of Little Lorikeet data between 1981 and 2005 from the database of the New South Wales Bird Atlasers indicates that the species was detected in 43 one-degree grid cells containing five or more bird surveys per year (NSW Scientific Committee 2007). Compared to the Atlases of Australian Birds (Blakers et al. 1984; Barrett et al. 2003), these NSW data were collected using consistent methods over time and are based on continuous survey records which allow a more statistically powerful analysis of trends. A linear regression fitted through the yearly averages indicates a reduction of 66% in the reporting rate over the 24-year period. For the last 15 years of data (1990 - 2005) the average reporting rate in the 43 grid cells was 8.3%, with a 61% reduction in reporting rate over the 15-year period. Given that reporting rate is only a presence/absence measure of abundance, and that flock sizes of Little Lorikeets are believed to have declined (Courtney & Debus 2006), the 61% reduction in reporting rate is likely to underestimate the change in abundance over the 15-year period, although there is considerable uncertainty in this estimate. From these data it appears that there has been at least a moderate reduction in population size over the past 15 years or three generation lengths, a time frame appropriate to the life cycle of the species.
9. The major threats to Little Lorikeets are loss of breeding sites and food resources from ongoing land clearing. Most breeding records come from the western slopes, where there has been extensive loss of the woodland habitat of the species due to historic land clearing. Loss of nest trees from road-side verges, often associated with road works, remains an ongoing threat. Of 50 nest hollows studied by Courtney & Debus (2006), 40% were lost during the 43-year study. Many of these losses were anthropogenic, with five nest trees destroyed by bulldozers, three nest trees burnt and two nest hollows taken over by feral honeybees. New nest hollows are not being recruited at a rate that compensates this loss, because overgrazing by livestock prevents the establishment of eucalypt seedlings and smooth-barked eucalypts are not favoured species in farm revegetation works (Courtney & Debus 2006). Extensive loss of eucalypt woodlands will also have resulted in a large reduction in food availability for this species. ‘White Box, Yellow Box, Blakely's Red Gum Woodland’, an important habitat for the Little Lorikeet, is listed as an Endangered Ecological Community under schedule 1 of the Threatened Species Conservation Act 1995 .‘Clearing of native vegetation’, ‘Loss of hollow-bearing Trees’, ‘Competition from feral honeybees Apis mellifera L.’, and ‘Infection by Psittacine Circoviral (beak and feather) Disease affecting endangered psittacine species and populations’ are listed as Key Threatening Processes under schedule 3 of the Threatened Species Conservation Act 1995.
10. The Little Lorikeet Glossopsitta pusilla (Shaw, 1790) is not eligible to be listed as an Endangered or Critically Endangered species.
11. The Little Lorikeet Glossopsitta pusilla (Shaw, 1790) is eligible to be listed as a Vulnerable species as, in the opinion of the Scientific Committee, it is facing a high risk of extinction in New South Wales in the medium-term future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2002:
Clause 14
The species has undergone, is observed, estimated, inferred or reasonably suspected to have undergone or is likely to undergo within a time frame appropriate to the life cycle and habitat characteristics of the taxon:
(c) a moderate reduction in population size
based on:
(d) an index of abundance appropriate to the taxon
Dr Richard Major
Chairperson
Scientific Committee
Proposed Gazettal date: 31/07/09
Exhibition period: 31/07/09 - 25/09/09
References:
ABBBS (2008) Bird and bat banding. Accessed at http://www.environment.gov.au/biodiversity/science/abbbs/index.html
Barrett G, Silcocks A, Barry S, Cunningham R, Poulte, R (2003) ‘The New Atlas of Australian Birds’. (Birds Australia, Melbourne)
Blakers M, Davies SJJF, Reilly PN (1984) ‘The Atlas of Australian Birds’. (Melbourne University Press: Melbourne)
Courtney J, Debus SJS (2006) Breeding habits and conservation status of the Musk Lorikeet Glossopsitta concinna and Little Lorikeet G. pusilla in Northern New South Wales. Australian Field Ornithology 23, 109-124.
French K, Paterson I, Miller J, Turner RJ (1993) Nectarivorous bird assemblages in Box-Ironbark Woodlands in the Capertee Valley, New South Wales Emu 103, 345-356
Garnett ST, Crowley GM (2000) ‘The Action Plan for Australian Birds’. (Environment Australia: Canberra)
Higgins PJ (Ed) (1999) ‘Handbook of Australian, New Zealand and Antarctic Birds - Volume 4 - Parrots to Dollarbird’. (Oxford University Press: Melbourne)
Horton P, Black AB (2006) The Little Lorikeet in South Australia, with notes on the historical status of other lorikeets. South Australian Ornithologist 34, 229-243.
IUCN (2008) ‘Guidelines for using the IUCN Red List Categories and Criteria. Version 7.0.’ (Standards and Petitions Working Group of the IUCN Species Survival Commission Biodiversity Assessments Sub-committee: Switzerland)
NSW Scientific Committee (2007) Little Lorikeet analysis November 2007. Hurstville
Smyth A, MacNally R, Lamb D (2002) Influence of forest management and habitat structural factors on the abundances of hollow-nesting bird species in subtropical Australian eucalypt forest. Environmental Management 30, 547–559
