Fig. 5. Stomach temperatures (°C) of double-crested cormorants during rest at night and during the day, during resting in `warm' and `cold' water (triangles) and during shallow diving in `cold' water (open circles; values are grand means ± 1 s.d.; N=9 birds). `Day (avg)' is the mean stomach temperature during the hours of daylight (from sunrise to sunset), which includes periods of food ingestion. Air temperatures ranged from 10 to 26°C during the day and 0–11°C during the night. All temperature values were significantly different from the `day rest' value. *Significantly different from `resting in water' values.