Grantee Research Project Results
Using Raptor Pellet-Derived Small-Mammal Death Assemblages For Paleoecological Reconstruction: A Late Holocene Case Study In The Northern Great BasinEPA Grant Number: F5F21867
Title: Using Raptor Pellet-Derived Small-Mammal Death Assemblages For Paleoecological Reconstruction: A Late Holocene Case Study In The Northern Great Basin
Investigators: Terry, Rebecca C.
Institution: University of Chicago
EPA Project Officer: Manty, Dale
Project Period: September 1, 2005 through September 1, 2008
Project Amount: $111,172
RFA: STAR Graduate Fellowships (2005)
Research Category: Academic Fellowships
The primary objectives of my research are
- to quantify the extent to which Holocene raptor pellet derived small-mammal death-assemblages capture a true ecological snapshot of the living small-mammal community (“ecological fidelity”),
- and to apply these insights to a faunal analysis of late Holocene fossil material from Homestead Cave, Utah.
Stratified small-mammal deposits associated with long-term raptor roosts have the potential to record a time-series of small-mammal community restructuring brought on by Holocene environmental shifts. I am conducting the first explicit “live/dead” analysis of small-mammal death assemblages to investigate their ecological fidelity. “Dead data” are generated by sieving dead remains from sediments accumulating in the target area, and “live data” are derived from modern trapping surveys of the local living community. I plan to combine this analysis with 14C dating of skeletal remains to investigate the magnitude of time represented by a single stratigraphic horizon and understand the dynamics of dead cohort loss from the fossil record. In addition, I am conducting a faunal analysis of the late Holocene small-mammal community recovered from Homestead Cave, Utah.Expected Results:
Quantifying the magnitude and direction of ecological bias is critical to accurate paleoecological reconstruction, while establishing how much time is represented by a particular fossil assemblage dictates the temporal resolution at which paleoecological questions can be asked. Analysis of the late Holocene small-mammal fossil record from Homestead Cave, Utah, will increase our understanding of small-mammal community restructuring in response to
- the onset of relatively mesic conditions in the late Holocene,
- sudden warming during the Medieval Warm Period,
- and shifts in vegetation due to the recent invasion of Cheat Grass (Bromus tectorum) in the desert west.
Linking the Holocene (past 10,000 years) with the present through paleontological records is critical for predicting biotic response to natural and human-induced environmental changes and effectively protecting biodiversity in the future.Supplemental Keywords:
Taphonomy, paleoecology, geohistorical records, historical ecology, community ecology, faunal analysis, mammals, raptors, owl pellets, radiocarbon, absolute dating, Utah, Great Basin, Holocene,, RFA, Scientific Discipline, Air, Ecosystem Protection/Environmental Exposure & Risk, climate change, Air Pollution Effects, Habitat, Environmental Monitoring, Atmosphere, Environmental History, habitat dynamics, faunal analysis, Raptor death assemblages, community composition, environemental history, Halocene period, habitat disturbance, invasive plant species, ecological consequences