The honeybee (Apis mellifera) travels considerable distances to collect food. But before a bee can become a forager, it takes orientation flights so that it can navigate back to the colony. Earlier studies, based on observation, have only been able to explore bee flight in the immediate locality of the hive, so little is known about how bees learn to find their way around when they are further from home. Now Elizabeth Capaldi at the University of Illinois and colleagues have successfully monitored the more distant reaches of a honeybee's wanderings.

The group tagged day-old adult worker bees with numbered discs, introduced them to a colony and monitored their flight activity around the hive. All those returning with pollen or nectar -- 'foragers' -- had taken between one and eighteen orientation flights, the researchers report in Nature1.

Capaldi's team repeated the process with another colony. They then selected bees of various ages and flight histories. The researchers fitted tagged honeybees with transponders and used harmonic radar to follow a single orientation flight for each bee. This technique, pioneered by one of the team, J. R. Riley, means that the bees can be tracked without the clutter of ground features reflecting radar.

Journey times did not vary much between earlier and later flights -- but more experienced bees seemed to travel further afield. Evidently the bees flew faster as they gained experience.

Capaldi suggests that the bees took a number of orientation flights so that they could visit a larger area around the hive, viewing it and the surrounding landscape from different positions. This may mean that honeybees learn about their environment progressively -- in stages, in other words, according to their individual needs.

Bees modify their flight speed so that the images they see move at a constant rate. As they gain experience, they soar at a higher altitude to keep this 'image speed' stable. This means that that honeybees are probably very familiar with the immediate area surrounding their hives but have a more general awareness of the larger landscape.

Now multiple flights of individual bees will need to be studied for bees' learning processes to be more fully understood. 'This is the beginning," says Professor Tom Collett of the University of Sussex, UK, "we don't know whether orientation flights are made in the area where the bee will later forage." Nonetheless, the findings of Capaldi and her colleagues are an important first stage in understanding the process of how honeybees learn to get home.