Table 2 Comparison of chick counts between Penguin Watch (CS) and GS data for four cameras: DAMOa, HALFc, LOCKb and PETEc; see Table 1 legend for definitions.

DAMOa

n=300

n=60

Average difference

0.25

0.27

0.29

0.33

1.25

1.33

1.45

1.65

σ

0.68

0.71

0.75

0.85

1.04

1.05

1.06

1.20

Proportion of differences that are 0 or 1

0.94

0.93

0.92

0.91

0.68

0.67

0.60

0.53

HALFc

n=283

n=109

Average difference

0.46

0.51

0.58

0.65

1.18

1.31

1.50

1.69

σ

0.89

0.99

1.11

1.24

1.09

1.22

1.35

1.50

Proportion of differences that are 0 or 1

0.90

0.87

0.83

0.82

0.73

0.65

0.57

0.54

LOCKb

n=300

n=122

Average difference

0.94

0.90

0.88

0.92

2.32

2.22

2.16

2.25

σ

2.21

2.08

2.07

2.12

2.97

2.79

2.79

2.84

Proportion of differences that are 0 or 1

0.81

0.81

0.83

0.80

0.53

0.53

0.59

0.52

PETEc

n=300

n=179

Average difference

1.89

2.07

2.49

3.06

3.17

3.46

4.17

5.12

σ

2.69

2.69

3.12

3.70

2.85

2.71

3.06

3.51

Proportion of differences that are 0 or 1

0.60

0.55

0.52

0.49

0.33

0.25

0.20

0.15