The composition of seed banks on kangaroo rat (Dipodomys spectabilis) mounds in a Chihuahuan Desert grassland

Disturbance is a major factor determining the plant community structure of ecological systems. In particular, small-scale disturbances from animals can increase heterogeneity and species diversity in plant communities. Kangaroo rat (Dipodomys spectabilis) mounds are small-scale disturbances that support unique plant communities compared to surrounding habitats. The seed bank, which is usually an overlooked part of plant communities, is an important trait of some plant species that allows for their persistence in unpredictable environments. To further understand how small-scale disturbances by kangaroo rats affect the plant community in Chihuahuan Desert grassland, we studied the composition of the seed bank for eight forb taxa on and off kangaroo rat mounds. Kangaroo rat mounds accumulated more seeds and supported different seed compositions than the adjacent grassland. Also, kangaroo rat mounds had different microhabitats than areas away from the mound. This suggests that kangaroo rat mounds facilitate some plant species by providing microhabitats that contain ‘safe sites’ for seeds to accumulate where adult plant populations can establish and colonize thus increasing plant diversity and altering plant structure in communities. 2010 Elsevier Ltd. All rights reserved.