The global bedbug resurgence has left the scientific community racing to fill large gaps in our understanding of the biology and ecology of this forgotten pest. Studying the ecology of a species so closely associated with humans has inherent difficulties, necessitating the development of laboratory arenas that replicate natural infestations. The arena developed herein provides bedbugs with the opportunity to exhibit natural foraging, hiding and dispersal behaviours on a scale that reflects their natural environment.
Using this arena I test hypotheses relating to; 1) how bedbugs use harbourage space, and 2) the factors affect their dispersal. My research revealed that harbourages in the vicinity of the host are used first and peripheral harbourages only form as the infestation develops. The preferential use of harbourages adjacent to the host is explained by the finding that feeding frequency was negatively correlated with distance from the host. However, despite this advantage of residing in close proximity to the host, bedbugs form discontinuous harbourages, leaving regions of unoccupied space. This suggests that there are factor(s) that limit harbourage density.
Female dispersal was unaffected by males presence, suggesting that sexual harassment does not drive dispersal in the bedbug. However, variation in the distribution of the sexes across harbourages suggests that females may be able to avoid males through harbourage selection.
Increased harbourage availability significantly delayed the onset of dispersal, suggesting that competition for harbourages near the host is a factor driving dispersal from the natal infestation. Given that a host is an almost unlimited food source and that the cost of dispersing is likely to be high, it is not immediately apparent why bedbugs choose to actively disperse. However, theoretical models show that where relatedness is high, dispersal always occurs to reduce competition. The high cost of dispersal may therefore be offset by kin selection.
