Post on 04-Feb-2022
transcript
Is killing goats and burning bush the answer?
Achieving conservation outcomes on St Bees Island National Park
Dr Rhonda Melzer, Ecological Assessment Unit, Conservation Management Branch, QPWS
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Impacts …… Values ….. Desired outcomes
From grazing property to National Park
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2001 2007
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Management objectives
• Maintain or restore the distribution, structure & composition of the vegetation communities
• Maintain the koala population and its habitat – in particular the E. tereticornis (Qld blue gum) woodlands
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So what are we doing to achieve our objectives?
Monitoring plots est. Oct 2006
Goat culling commenced Oct 2007
Lantana spraying – 2007
Detailed veg. mapping – 2009
1st planned burn – 2009
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Are we heading in the right direction?
3 sites:• Exclosure
• Open plot
Additional:
Photo points& transects in grasslands
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Are we heading in the right direction?
• Foliage projective cover – overstorey• Leaf area index – overstorey• Density/basal area – woody species• Foliage projective cover – understorey• Species presence & abundance –
ground stratum• Recruitment woody species• Photo monitoring
• Koala population
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Woodland
0
2.5
5.0
7.5
10.0
2006 2007 2008 2009
% bare soil - woodland plots
% b
are
soil
ExclosureOpen plot
0
250.00
500.00
750.00
1000.00
2006 2007 2008 2009
Biomass - woodland plots
g/m
2
ExclosureOpen plot
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Woodland cont.
0
150.0
300.0
450.0
600.0
2006 2007 2008 2009
Relative increase (%) in rainforest tree seedlings in the woodland plots
%
ExclosureOpen plot
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‘Grassland’
0
275.00
550.00
825.00
1100.00
2006 2007 2008 2009
Biomass - grassland plots
g/m
2
ExclosureOpen
0
3.8
7.5
11.3
15.0
2006 2007 2008 2009
% bare soil in grassland plots
% b
are
soil
ExclosureOpen plot
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Grassland – on the way back
Exclosure 2009
‘Exclosure’ - 2006
0
10.00
20.00
30.00
40.00
2006 2007 2008 2009
Mean % cover Imperata cylindrica
% c
over
/m2
ExclosureOpen
0
25.00
50.00
75.00
100.00
2006 2007 2008 2009
Mean % cover Aristida personata
% c
over
/m2
ExclosureOpen
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2007
2009
2007
2009
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2007
2009
2007
2009
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2007
2009
2007
2009
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2007
2009
2007
2009
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So – is killing goats and burning bush the answer?Killing goats:• ↑ ground stratum cover & biomass (+)• ↓ bare ground (↓ erosion) (+)• ↑ spp. richness (+)• Recovery of native herbaceous spp. (+)• ↑ recruitment of woody spp. (+/–)• E. tereticornis seedlings sighted! (+)• Lantana suppression reduced (–)
Adding fire management to the equation:• Prevent rainforest expansion into areas where we want to
maintain woodland & grassland• Provide suitable habitat conditions for eucalypt regeneration• Help restore species diversity in grasslands• Facilitate lantana control
A necessary evil for koalas….a juggling act for us!
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So – is killing goats and burning bush the answer?Killing goats:• ↑ ground stratum cover & biomass (+)• ↓ bare ground (↓ erosion) (+)• ↑ spp. richness (+)• Recovery of native herbaceous spp. (+)• ↑ recruitment of woody spp. (+/–)• E. tereticornis seedlings sighted! (+)• Lantana suppression reduced (–)
Adding fire management to the equation:• Prevent rainforest expansion into areas where we want to
maintain woodland & grassland• Provide suitable habitat conditions for eucalypt regeneration• Help restore species diversity in grasslands• Facilitate lantana control
A necessary evil for koalas….a juggling act for us!
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Acknowledgements
QPWS staff – Central Marine Region• Caleb Bailey• Kerensa McCallie• Steve Burke• Steve Fisher• Ross Courtenay
QPWS staff – Ecological Assessment Unit• John Clarke• John Olds
Dr Alistair Melzer, Koala Research Centre of Central QldDr Bill Ellis, Koala Study Program University QldEarthWatch volunteers
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