Recovery challenges for the Forty-spotted Pardalote on its island refugia. Dr Sally Bryant Tasmanian Land Conservancy

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1 Recovery challenges for the Forty-spotted Pardalote on its island refugia Dr Sally Bryant Tasmanian Land Conservancy

2 40 Spotted Pardalote the Story so Far Thirteen years ago it was with surprise and elation that we discovered a new colony of Forty-spotted pardalote, just 20 minutes south of Hobart at the Peter Murrell Reserve, Howden. The future survival for one of word often used but seldom is it more appropriate in this case. -spotted Pardalote is about 9 cm long and weighs less than 9 grams. Unlike quiet, shy, and lives in colonies that are sedentary from year to year. The species is intrinsically linked to one Eucalypt species, Eucalyptus viminalis or White Gum, which provides its critical food sources of invertebrates, lerp and sugary manna, especially for the young during breeding time. The Forty-spotted Pardalote favours areas with low rainfall, fertile soils and high annual mean. This extensive colonies were once on Flinders Island, Maria Island, Bruny Island, Tinderbox Peninsula, Tasman Peninsular, Coningham Peninsula, Howden and the slopes of Taroona. The species has always been considered naturally rare and even though its colonies are widely scattered, nowhere has it ever been common or numerous. The nationally endangered status is due to its small area of occupancy, fragmented distribution, and projected decline in extent and quality of habitat. The first extensive survey of the Forty-spotted Pardalote was in 1986 by Peter Brown, who estimated a total population of ~ 3,500 birds. A second assessment during the mid-1990s estimated a similar population size and included a few new colonies in existing locations. The similarity in the two population estimates suggested the species was probably fairly stable over this time period and may have even reached maximum carrying capacity across its range. Forty-spots were flourishing on Maria Island National Park, on Bruny Island at Dennes Hill State Reserve and Partridge Island, in the Darling Range on Flinders Island, and a host of other small reserves across its range. Colonies were well known and mapped on local council planning schemes, and the species appeared to be at no immediate risk of extinction. Unfortunately, one key factor was overlooked its critical reliance on White Gum, a eucalypt which is highly susceptible to drought, and Tasmania was currently experiencing a severe drought over the intervening 20 year period.

3 During , a re-assessment of the population gave alarming results. The species had declined dramatically across its range, with a population totalling less than 1,500 birds equating to a 60% decline in 15 years. 3 mainland sites were extinct as were 6 colonies on Bruny Island due to 100% death of white gum. The colony at Peter Murrell Reserve was in complete decay with birds becoming increasingly difficult to find with every visit. Modelling using IUCN criteria predicted that the species could potentially be extinct within the next 10 to 15 years without active drought, exacerbated by secondary factors such as displacement due to changing bird communities favouring more aggressive and competitive species. Unfortunately, the story is not straightforward nor does it fit neatly into the impacts of drought. Recent surveys on Flinders Island in 2010 and 2011 identified large intact patches of white gum forest across the island containing mixed age stands in seemingly healthy condition, yet only a total of 6 individual birds could be found. Colonies once occurring in the mid-region of Flinders Island may now well be extinct due to a severe wildfire in 2002/3, with little hope of them recolonizing due to fragmented habitat and a lack of feeder colonies. While there is still more survey to do, drought is not the cause of the species decline on Flinders Island, hence other, probably ecological factors, are operating. If we are to recover the Forty-spotted Pardalote then the decisions to make are immediate and the tasks varied vegetation efforts will afford the species a better long-term future, but in the short term, active recovery intervention is needed. While the priority for long term survival of this species is still to protect existing colonies and plant linkage corridors, it is our efforts in the short to medium term on off shore islands which will save it from extinction. Assisted migration to Flinders Island, identification of additional islands containing white gum, possibly Il de Phoque, Cape Barren, Schouten, Betsey, further south to Blubber Head and the Dover region these are all potential recovery actions which need to be explored with some urgency. Continued monitoring is essential. The fall-out of partial, instead of full funding of recovery actions, has meant large gaps in our ecological knowledge of the species requirements which may hold clues to additional reasons for their decline. Thank you

4 Ecology Endemic White Gum Sedentary Territorial Colonial Poor Dispersal

5 Distribution 2011 Flinders Island Maria Island Howden / Tinderbox Bruny Island

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8 Nationally Endangered Area of occupancy <500km 2 Habitat severely fragmented Continuing decline projected Threats ongoing Image E. McDonald

9 Recovery Actions ( ) Habitat Protection Corridors & Links Education Ecology Monitoring Habitat Requirements

10 80% colonies protected Replanting underway Improved prescriptions & planning Greater awareness Image S Bryant

11 Image C Tzaros

12 Findings % Pop decline 85% Colonies decline Colonies <10 ha at risk 68% colonies degraded 3 Mainland sites extinct 6 Bruny colonies extinct

13 Population Changes Site Flinders NA Maria 1,700 1,700 < 900 Bruny 1,700 1, Other Total 3,500 3,800 1,400 Image P. Geard

14 Flinders Island 1997 status 70 birds in 3 colonies Wildfire in 2003 No birds 2005 survey Healthy habitat

15 Findings 3 colonies extinct 6 birds? Good habitat Other Factors

16 Where to Now? Reintroduction Translocation Ex-situ relocations to other islands Assisted colonisation to Flinders Island in the absence of genetic information Re-enforcement of existing colonies Is extinction inevitable? Image P. Fraser

17 Lessons Learned 100% Funding needed Keep Monitoring Planting takes Time Things Change Image P Geard