Improving Fox Management Strategies in...

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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

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.

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%

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%

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

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

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

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 N

O N

i

ii p

ON

ˆˆ

iN p

Oi

F̂i

A

A

FOD ii

i

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

2

21ˆm

nnN

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)