Geographical Ecology of Gerbilline Rodents in Sand Dune Habitats of Israel

Abstract

In Israel, sand dune habitats of varying sizes occur along a rainfall gradient ranging from 30 to 650 m. In these sand dunes, nine species of granivorous rodents are found, eight of which belong to the family Gerbillidae. Rodent species were sampled during the four main seasons in eleven different locations covering the major sand dune habitats. Both species and their equivalent biomass were highly and significantly correlated with the mean annual rainfall. As the amount of rainfall increased, so did the number of species and their equivalent biomass. However, once a certain amount of rainfall was reached, an additional increase in rainfall was followed by a decrease in species number and biomass. Mean annual rainfall was similarly correlated with % annual cover, an index of the size of the seed crop on which the rodents feed. Number of rodent species was also significantly correlated with the area of the sand dune habitats. Analysis suggests that both rainfall and area are important in determining species number. Most of the patterns of community structure found in Israel are similar to those reported for the rodents that occur in the sand dunes of the desert of the western U.S.A.