How do procellariiform birds recognize mates at crowded breeding colonies?

In crowded breeding colonies, procellariiform birds—a group that includes albatrosses, shearwaters, and petrels—rely on specific behaviors and sensory cues to recognize their mates.12

Because many burrowing species, such as shearwaters and petrels, meet on land only at night, they may never see their mates clearly while ashore. In these cases, recognition is achieved through a combination of voice, touch, and possibly smell.2

At each encounter, breeding pairs engage in an elaborate greeting ceremony, which involves clashing and fencing with their bills while cackling and screaming. For albatrosses, which are diurnal, these interactions also include bowing and dancing displays. These behaviors serve multiple purposes: they provide the necessary time for mate recognition and help to relieve or displace any natural aggression or fear between the birds. While visual and auditory stimuli are primary, researchers suggest that odor may also play a role in mate recognition for some petrels and shearwaters.23