Thick-billed Murre - Flight and Feeding Characteristics

Flight and Feeding Characteristics

The Thick-billed Murre's flight is strong and direct, and they have fast wing beats due to the short wings. Like the other auks, these birds forage for food by using their wings to 'swim' underwater. They are accomplished divers, reaching depths of up to 150 m and diving for up to four minutes at a time; usually however birds make either shallow short dives or dive down to 21–40 m for longer periods. While hunting, the diving trajectory resembles a flattened 'U'. Birds will make long trips to get to favorite feeding grounds; while they usually forage several dozen km from their nest sites, they often travel more than 100 km to fish..

The diving depths and durations regularly achieved by these birds indicate that they, and similar auks, have some - as yet unknown - mechanism to avoid diving sickness and lung collapse when surfacing. It is postulated that auks temporarily absorb excess gases into the vascular structure of their bones. From there, it is gradually released from temporary storage in a controlled process of decompression.