1. Bob Schooley, University of Illinois, Jornada LTER Brandon Bestelmeyer, USDA-ARS, Jornada LTER Andrea Campanella, Sierra Nevada Research Institute John Anderson and LTER Field Crew Temporal Dynamics of Animals across Ecological States

2. Consequences of grassland-to-shrubland state transitions on abundance, biomass, and energy flux of important consumer group—desert rodents. Importance of bottom-up (precipitation, ANPP) and top-down (predators) effects and potential role of time lags and legacies.

3. Does Portal generalize to other North American arid ecosystems?

4. The Ecotone Study: design and sampling Grassland Ecotone Mesquite Shrubland Grassland Ecotone Mesquite Shrubland Grassland Ecotone Mesquite Shrubland 3-ha livetrapping grid on each plot; sampled once per year in October Continuous data from 2004 to present Data set includes captures of 3,685 individuals

5. Shrub cover alters species biomass and community composition

6. Strong temporal variation in overall rodent abundance and biomass consistent across ecological states Habitat x Year p = 0.985 Habitat x Year p = 0.963

7. Granivores Herbivores Temporal dynamics of trophic groups Periodic colonization by hispid cotton rat

8. Rodent abundance related to lagged summer precipitation

9. Habitat p = 0.172 Summer rain (lag 1) p < 0.001 Summer rain (lag 1) 2 p < 0.001 Winter rain p < 0.001 Rodent abundance related to lagged summer precipitation

10. Negative effects of winter rain on rodent abundance differ by trophic group Herbivores Habitat p = 0.165 Summer rain (lag 1) p < 0.001 Summer rain (lag 1) 2 p < 0.001 Winter rain p = 0.003 Habitat p = 0.446 Summer rain (lag 1) p < 0.001 Winter rain p = 0.180 Granivores

11. Habitat p = 0.653 ANPP (lag 1) p = 0.045 ANPP (lag 1) x Habitat p = 0.180 Primary Production and Rodent Biomass: Legacies and Lags Habitat p = 0.695 Summer rain p = 0.709 Winter rain p = 0.413 Models for predicting ANPP Habitat p = 0.744 Summer rain p < 0.001 Winter rain p = 0.142 ANPP (lag 1) p = 0.555 Legacy effects sensu Sala et al. 2012 (g/m 2 )

12. Year (t-2) Year (t – 1) Year (t) ANPP Rodent abundance and biomass Summer precipitation Winter precipitation Current model of bottom-up effects on desert rodents across ecological states

13. Future Plans 1.Extend long-term data set on desert rodent communities across mesquite shrub gradients and further explore complexities of bottom-up effects. 2.Determine if considerable unexplained variance is related to top-down effects due to predator distribution and activity. In 2014, established array of camera traps to non-invasively sample carnivores (and lagomorphs). Camera traps deployed on 24 sites representing shrub gradient including 9 sites on the Ecotone study. Two cameras per site (48 total cameras) are operated for 2 months each year from July to September. Response variables: site occupancy probability and photo-activity rate