|Group is moving steadily in a constant direction more quickly than the idle speed of the observing vessel. Swimming with short, relatively constant dive intervals. Group spacing varies.
|Group is moving steadily in a constant direction more slowly than the idle speed of the observing vessel. Swimming with short, relatively constant, synchronous dive intervals. Individuals are tightly grouped.
|No net movement. Individuals are surfacing facing in different directions. The group often changes direction as well. Dive intervals are variable but short. Group spacing varies.
|Direction of movement varies. Group dives synchronously for long intervals. All individuals perform "steep dives," arching their backs at the surface to increase their speed of descent. Group spacing varies. Diving most likely represented the "feeding" category in other studies (Shane 1990).
|Many diverse interactive behavioral events are observed, such as body contacts, pouncing, genital inspections, and hitting with tail. Individuals often change position in the group. The group is split in small subgroups that are spread over a large area. Dive intervals vary.