improving fox management strategies in australia...fox baiting should be encouraged, it is also...
TRANSCRIPT
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D E P A R T M E N T O F A G R I C U L T U R E , F I S H E R I E S A N D F O R E S T R Y
Improving Fox Management Strategies in AustraliaGlen Saunders and Lynette McLeod
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The European red fox was introduced into Australia in the 1870s for recreational hunting. Their subsequent spread was rapid and
they are now responsible for environmental and agricultural impacts valued at over $200 million per annum.
Despite greater public awareness about feral cats, foxes are considered
to be Australia’s greatest predation threat to the survival of native fauna –
particularly relevant given their recent introduction to Tasmania.
Foxes are also widely regarded as a major threat to lamb production,
although it is important to recognise that many factors involved in
poor lambing percentages are inconspicuous, whereas damage
inflicted by predators is usually highly visible.
There have been surprisingly few scientifically-rigorous studies to confirm
or refute many of the perceived impacts of foxes on agriculture and the
environment. The need for further impact and cost–benefit studies is a
common theme in this review.
Over the past decade there has been a dramatic increase in the use of
1080 fox baits, and whilst the continuing trend toward coordinated regional
fox baiting should be encouraged, it is also important to
ensure that such baiting is conducted effectively, particularly
considering that recent surveys suggest that fox impacts
may be increasing in many areas.
This report provides a comprehensive review of fox management
strategies along with impacts and monitoring techniques. This
includes a critical appraisal of past research studies and ongoing fox
management programmes. A key finding is that problems with the
experimental design and analysis of research and management has
sometimes hindered progress in defining fox impacts and determining the
best approach to reducing these impacts.
This report offers a set of key recommendations for consideration
by research agencies, land managers and policy-makers to
improve and harmonise approaches to measuring and
managing fox impacts.
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1080 poison baiting 76.7%
Fox drives 0.4%
Guard animals 3.6%
Den fumigation 2.2%
Exclusion fencing 1.4%
Trapping 2.3%
Ground shooting 13%
Other 0.4%
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Foxoff® baits 48%
Heart 0.68%
Tongue 2.42% Kidney 0.03%
Liver 5.67%
Unspecified red meat 14.03%
Lamb 0.62%Horse 1.01%Beef 0.19%
Sausage 0.32%
Chicken heads 16.65%
Chicken wingettes 9.74%
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Baiting Strategy
< 7 days
> 7 days
Cost-effectiveness
Cost-effectiveness
Min cost per lethal bait presented
Min cost per bait consumed
Min cost per bait consumed
Min cost of bait procurement
Min cost of bait distribution
Min number of baits required
Min number of procurements
Min replacement
Min persistence
Min caching
Min uptake
Min cost per bait presented
Min total cost per bait consumed
Min total cost per bait consumed
Min total cost
Min total cost
Min persistence
Min caching
Min uptake
Longevity
NONE
7-14 days
> 14 days
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
DOC/WINGETTE
FOXOFF
FOXOFF
FOXOFF
FOXOFF
FOXOFF
FOXOFF
FOXOFF
FOXOFF
FOXOFF
Non-target safety
Non-target safety
Handling
No replacement
Replacement
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0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Rel
ative
Pay
off
-
0
1
2
3
4
5
6
J F M A M J J A S O N D J F M A M
April only
July only
Nov only
No Control
J J A S O N D J F M A M J J A S O N D
Month
Den
sity
(fo
xes/
km2 )
0
1
2
3
4
5
6
J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D
Month
Den
sity
(fo
xes/
km2 )
April only
July only
April and July
No Control
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J F M A M J J A S O N D
Peak fox energy gain
Birth of fox cubs
Pre vixen pregnancy
Lowest fox pop. numbers
Juvenile fox dispersal
Lambing periodSpringAutumn
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0
100
200
300
400
500
600
1979
/80
1981
/82
1983
/84
1985
/86
1987
/88
1989
/90
1991
/92
1993
/94
1995
/96
1997
/98
1999
/00
2001
/02
2003
/04
Num
ber (
x100
0)
-
Mound of soil
fcd
e
b
a
Ground level
-
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
1980 82 84 86 88 90 92 94 96 98 2000 02
1080
(g)
-
O N
p
p O NO N
p̂
N̂
i
ii p
ON
ˆˆ
iN p
Oi
F̂i
A
A
FOD iii
ˆˆ
Di
-
fx
f = 1–e x
x
-
F
F = S / KD
SK
D
F
SL
LD
NP
F = ________SLt
Ln DNP
-
n1
n2
m2
N̂
2
21ˆm
nnN
p̂
Oi
-
N1 = (I
1C)/(I
2 – I
1) and,
N2 = (I
2C)/(I
2 – I
1)
I1
I2
C
-
Pest Abundance
Dam
age
(i)
(ii)
(iii)