Individual foraging patterns of the jack jumper ant Myrmecia croslandi (Hymenoptera: Formicidae)

In ants, we know most about the foraging patterns at the colony level. We know surprisingly little about the foraging behaviour of individual foragers and how they shape the behaviour of the colony. To identify spatial and temporal variation in foraging behaviour at the individual level, we studied at two nests the solitary foragers of the Australian jack jumper ant Myrmecia croslandi TAYLOR, 1991. These ants are strictly diurnal and active only between October and April. Foragers of Myrmecia croslandi have a long life span (about a year) and we took advantage of this to determine the variation in their time of activity and foraging paths over a two-year period. By tracking the outbound paths of foraging ants using a Differential GPS we discovered that: (a) individual ants use very different routes to reach the same destination; (b) distance travelled by foragers was longest (up to 15 m) when they travelled to nest-specific eucalypt trees on which they foraged either for prey or tended to sap-sucking insects; (c) and ants made short forays (< 2 m) into nontree sectors where they exclusively hunted for prey. Individual foragers exhibited temporal fidelity based on their nest departure times, and could be classified as those active (a) all day, (b) only within eight hours after sunrise and (c) only after eight hours after sunrise. By monitoring individual activity for seven consecutive days we show that individual ants carry out up to six trips per day and rarely forage on consecutive days.