Interference competition and temporal and habitat partitioning in two gerbil species

Tested two hypotheses which may explain two different patterns which underlie coexistence in two species of desert gerbils (Gerbillus allenbyi and G. pyramidum) in Israel. The two patterns are temporal partitioning of foraging activity and shared preference habitat selection. When sympatric, G. pyramidum uses the early part of the night most heavily while G. allenbyi is most active in the late part of the night. Although both species prefer the same habitat type (semistabilized sand dune), in the presence of G. pyramidum, G. allenbyi utilizes mainly the secondary habitat type (stabilized sand dune). Results supported the hypothesis that interference is the key factor to understanding the coexistence of the two species. Both the temporal and spatial patterns are the result of the dominant G. pyramidum species excluding the energetically efficient G. allenbyi from the preferred time of activity and habitat type. -from Authors