Trap-lining

In ethology and behavioral ecology, trap-lining or traplining is a feeding strategy in which an individual visits food sources on a regular, repeatable sequence, much as trappers check their lines of traps.

[2] This involves a specified route in which the individual traverses in the same order repeatedly to check specific plants for flowers that hold nectar, even over long distances.

Trap-lining has been described in several taxa, including bees, butterflies, tamarins, bats, rats, and hummingbirds and tropical fruit-eating mammals such as opossums, capuchins and kinkajous.

The term "traplining" was originally coined by Daniel Janzen,[4] although the concept was discussed by Charles Darwin and Nikolaas Tinbergen.

This theory has been tested, showing that bumblebees can remember the shortest route to the reward, even when the original path has been changed or obstructed.

When the group works together on finding a particular source of food they can quickly establish where it is and get the route information transferred to all the individuals in the population.

This means that organisms like bumblebees and hummingbirds can transfer pollen anywhere from the starting point of the route to the final food source along the path.

Since the path is always the same, it greatly reduces the risk of self-pollination (iterogamy) because the pollinator won't return to the same flower on that particular foraging session.

Under natural conditions they hypothesized that it would likely be beneficial for bees to prioritize higher reward flowers to either beat out competition or conserve energy.

The bees remember these complex flight paths by breaking them into small segments using vectors, landmarks and other environmental factors, each one pointing to the next destination.

[21] Despite a long history of research on bee learning and navigation, most knowledge has been deduced from the behavior of foragers traveling between their nest and a single feeding location.

[6] Only recently, studies of bumblebees foraging in arrays of artificial flowers fitted with automated tracking systems have started to describe the learning mechanisms behind complex route formation between multiple locations.

The demonstration that all these observations can be accurately replicated by a single learning heuristic model holds considerable promises to further investigate these questions and fill a major gap in cognitive ecology.