Evidence
Similarities between 79° and 70°, eg
- Feeding activity continuous / continues for 24 hours during polar day (summer months)
- feeding activity more intense in summer than in winter
- during times with a definite twilight period, (spring and autumn) feeding activity is
Predominantly diurnal
- during times with a definite twilight period, (spring and autumn) feeding activity is crepuscular (feeds at dawn and dusk).
Differences between temperatures:
At 79°
- arrhythmic in summer and winter
- had less night-time feeding activity in spring and autumn
- less intense feeding in summer
At 70°,
- arrhythmic during summer only
- during the winter showed diurnal patterns / crepuscular activity (feeds at dawn and dusk)
- had more night-time feeding activity in spring and autumn
- more intense feeding in summer