Table 2 Distance ratios in relation to the distance of the actual migration route, as calculated in this study, for simulated trajectories based on different compass mechanisms in five individuals of northern wheatear migrating between Alaska and Eastern Africa, as revealed by light-level geolocation (cf. [32]); see Fig. 4)

Autumn migration

Departure location

Arrival location

Distance of actual route (km)

Great circle route

Rhumbline route

Time-comp. sunset compass route

Fixed (menotactic) sunset compass route

Fixed (menotactic) magnetic compass route

Magnetoclinic compass route

B070

66°N, 145°E

13°N, 37°E

12840

0.88

1.17

0.88

1.01

1.15

–

E552

65.5°N,145.4°E

7°N, 30°E

14440

0.83

1.08

0.83

0.96

1.11

–

E553

68.6°N, 149.5°E

3°N, 30°E

13970

0.87

1.14

0.88

0.99

1.13

–

B801

65°N, 145°E

8°N, 34°E

13950

0.85

1.13

0.85

0.99

1.12

–

B823

65°N, 146°E

12°N, 31°E

14160

0.81

1.08

0.81

0.94

1.09

–

Spring migration

Departure location

Arrival location

Distance of actual route (km)

Great circle route

Rhumbline route

Time-comp. sunset compass route

Fixed (menotactic) sunset compass route

Fixed (menotactic) magnetic compass route

Magnetoclinic compass route

B070

12°N, 40°E

65.5°N,145.4°E

13310

0.86

1.13

0.92

0.98

1.11

0.99

E552

5°N, 30°E

66°N, 145°E

14270

0.85

1.10

0.94

0.97

1.14

1.01

E553

3°N, 30°E

68.6°N, 149.5°E

13450

0.90

1.19

0.98

0.98

1.19

1.04

B801

9°N, 36°E

65°N, 145°E

13370

0.88

1.18

0.95

1.00

1.15

1.03

B823

6°N, 31°E

65°N, 146°E

13620

0.89

1.17

0.96

1.03

1.19

1.04