Skip to main content

Table 3 Sampling effort needed to monitor guanaco population trends in Santa Cruz province, southern Patagonia

From: Guanaco abundance and monitoring in Southern Patagonia: distance sampling reveals substantially greater numbers than previously reported

  

Monitoring program scenario

  

50% in 5 years

50% in 10 years

  

Increase

Decrease

Increase

Decrease

  

α = 0.2

α = 0.3

α = 0.2

α = 0.3

α = 0.2

α = 0.3

α = 0.2

α = 0.3

 

Relative abundance

80

50

>120

90

40

20

80

60

All guanaco groups

Low

110

80

>120

>120

80

40

120

80

Medium

70

50

120

80

30

20

80

50

High

40

30

70

50

20

20

40

30

Breeding groups

Low

>120

>120

>120

>120

>120

>120

>120

>120

Medium

>120

>120

>120

>120

>120

>120

>120

>120

High

60

40

110

80

30

20

70

40

Non-breeding groups

Low

>120

>120

>120

>120

120

>120

80

>120

Medium

>120

70

>120

>120

60

40

120

90

High

70

50

120

80

20

20

70

50

Solitary individuals

Low

>120

120

>120

>120

90

60

>120

120

Medium

60

40

120

80

30

20

60

50

High

50

30

90

60

30

20

50

40

Breeding groups

 

>120

>120

>120

>120

>120

>120

>120

>120

Non-breeding groups

 

>120

100

>120

>120

70

50

>120

90

Solitary individuals

 

90

60

>120

100

40

30

90

60

  1. Sampling effort is expressed as the number of randomly located 30-km survey transects needed to attain the desired power of 1-β = 0.80 for each hypothetical scenario. Separate estimates of sampling effort are also given for areas with different combinations of classes of guanaco relative abundance and type of guanaco group. Estimates are also given after pooling all classes of relative abundance.