DOI: 10.5061/dryad.dbrv15fc9
title: Using dynamic foodscape models to assess bottom-up constraints on population performance of herbivores

description: Resource heterogeneity governs a multitude of ecological processes, but
 the mechanisms by which heterogeneity influences population performance
 are not fully resolved. Because optimizing behavior is challenging in
 heterogeneous landscapes, individual variation in foraging and movement
 strategies is common, and understanding the consequences of that variation
 is one of the most pressing challenges in modern ecology. In theory, such
 consequences should be modulated at least in part by nutrition, which
 directly influences discretionary energy available for growth and
 reproduction. We developed a series of linked dynamic models for
 predicting (i) spatiotemporal variation in the foodscapes available to
 seven distinct populations of elk (Cervus canadensis) in Idaho, USA, and
 (ii) variation in pregnancy rates among those populations as a function of
 foodscape use and availability. Foodscape models, which predicted
 variation in suitable forage biomass (biomass of forage that met or
 exceeded requirements of female elk at peak lactation), generally
 performed well, with adjusted R2 values ranging from 0.34 to 0.51.
 Patterns of foodscape use differed among populations and years, with some
 populations showing selection for the foodscape and others exhibiting
 indifference or even avoidance of high-quality forage resources. Pregnancy
 rates ranged from 66–100%, and our top model relating pregnancy to metrics
 of forage availability explained 41% of the variation among 20 elk
 population-years. Our top model relating pregnancy to foodscape use by elk
 explained 57% of the variation in pregnancy rates among 12
 population-years. Pregnancy rates were influenced more strongly by
 heterogeneity in foodscape use and availability than by differences in
 mean or maximum suitable biomass among populations. Our results suggest
 that population performance of elk was modulated both by the availability
 of high-quality forage and by factors that constrained use of the
 foodscape by elk. The dynamic modeling approach we developed for linking
 nutritional resources to herbivore performance is generalizable to many
 other species and systems, and can be used by wildlife managers to assess
 whether herbivore populations might be limited by bottom-up factors.
description: # Using dynamic foodscape models to assess bottom-up constraints on
 population performance of herbivores This is the README file for datasets
 contained in the publication: Sierra Robatcek, Ryan A. Long, Craig White,
 Lisa P. Shipley, Using dynamic foodscape models to assess bottom-up
 constraints on population performance of herbivores, Ecological
 Applications, 2025. Contact authors for all files: Ryan A. Long
 ([ralong@uidaho.edu](mailto:ralong@uidaho.edu)) **List of files included
 in data package:** **Macroplot Suitable Biomass Datasheets** 1.     
 DC_Summer_SuitableBiomass_Macroplots.xlsx 2.     
 DC_Fall_SuitableBiomass_Macroplots.xlsx 3.     
 SAW_Summer_SuitableBiomass_Macroplots.xlsx 4.     
 SAW_Fall_SuitableBiomass_Macroplots.xlsx 5.     
 SFORK_Summer_SuitableBiomass_Macroplots.xlsx 6.     
 SFORK_Fall_SuitableBiomass_Macroplots.xlsx **Elk Predicted Suitable
 Biomass Datasheets** 7.      DC_Summer_Predicted_SuitableBiomass_Elk.xlsx
 8.      DC_Fall_Predicted_SuitableBiomass_Elk.xlsx 9.     
 SAW_Summer_Predicted_SuitableBiomass_Elk.xlsx 10. 
 SAW_Fall_Predicted_SuitableBiomass_Elk.xlsx 11. 
 SFORK_Summer_Predicted_SuitableBiomass_Elk.xlsx 12. 
 SFORK_Fall_Predicted_SuitableBiomass_Elk.xlsx 13. 
 Beaverhead_Summer_Predicted_SuitableBiomass_Elk.xlsx 14. 
 Beaverhead_Fall_Predicted_SuitableBiomass_Elk.xlsx **Random Locations
 Predicted Suitable Biomass Datasheets** 15. 
 DC_Summer_Predicted_SuitableBiomass_Randoms.xlsx 16. 
 DC_Fall_Predicted_SuitableBiomass_Randoms.xlsx 17. 
 SAW_Summer_Predicted_SuitableBiomass_Randoms.xlsx 18. 
 SAW_Fall_Predicted_SuitableBiomass_Randoms.xlsx 19. 
 SFORK_Summer_Predicted_SuitableBiomass_Randoms.xlsx 20. 
 SFORK_Fall_Predicted_SuitableBiomass_Randoms.xlsx 21. 
 Beaverhead_Summer_Predicted_SuitableBiomass_Randoms.xlsx 22. 
 Beaverhead_Fall_Predicted_SuitableBiomass_Randoms.xlsx 23. 
 Salmon_Summer_Predicted_SuitableBiomass_Randoms.xlsx 24. 
 Salmon_Fall_Predicted_SuitableBiomass_Randoms.xlsx 25. 
 Lemhi_Summer_Predicted_SuitableBiomass_Randoms.xlsx 26. 
 Lemhi_Fall_Predicted_SuitableBiomass_Randoms.xlsx 27. 
 Teton_Summer_Predicted_SuitableBiomass_Randoms.xlsx 28. 
 Teton_Fall_Predicted_SuitableBiomass_Randoms.xlsx **Nutritional Model
 Datasets** 29.  DC_FRESH_input.xlsx 30.  SAW_FRESH_input.xlsx 31. 
 SFORK_FRESH_input.xlsx **Pregancy Model Dataset** 32. 
 Pregnancy_Analysis_Sheet.xlsx **Shapefiles** 33.  Elk_MCP_shapefiles.zip
 **Additional Tables** 34.  Extra_Tables.docx **Descriptions of File
 Contents** 1.      **DC_Summer_SuitableBiomass_Macroplots.xlsx** – Values
 of covariates included in the top model for predicting suitable biomass in
 the Diamond Creek elk zone during summer (June 1 – July 31). XCOORD = X
 coordinate of the macroplot (UTM) YCOORD = Y coordinate of the macroplot
 (UTM) EVI = Values of the Enhanced Vegetation Index derived from Modis
 Elevation2 = Elevation at the macroplot location, squared CanCov = Percent
 canopy cover derived from LandFire AprilSWE = April snow water equivalent
 in cm from nearest Snotel site PVT = Potential Vegetation Type derived
 from LandFire cosAspect = Cosine of aspect (a measure of northness)  
 TotalBiomass = Total measured biomass of all forage plants in grams
 Predicted_SuitableBiomass = Suitable forage biomass estimated using the
 FRESH model SuitableBiomass (Kg/ha) = Estimated values of suitable forage
 biomass from previous column converted to kg/ha Predicted_SuitableBiomass
 (Kg/ha) = Predicted values of suitable forage biomass at the macroplot
 location derived from the final fitted foodscape model 2.     
 **DC_Fall_SuitableBiomass_Macroplots.xlsx** – Values of covariates
 included in the top model for predicting suitable biomass in the Diamond
 Creek elk zone during fall (August 1 – September 15). XCOORD = X
 coordinate of the macroplot (UTM) YCOORD = Y coordinate of the macroplot
 (UTM) PVT = Potential Vegetation Type derived from LandFire EVI2 = Values
 of the Enhanced Vegetation Index derived from Modis, squared MnPrecip =
 Monthly precipitation in cm derived from PRISM Elevation2 = Elevation at
 the macroplot location, squared Slope = Percent slope at the macroplot
 location TotalBiomass = Total measured biomass of all forage plants in
 grams Predicted_SuitableBiomass = Suitable forage biomass estimated using
 the FRESH model SuitableBiomass (Kg/ha) = Estimated values of suitable
 forage biomass from previous column converted to kg/ha
 Predicted_SuitableBiomass (Kg/ha) = Predicted values of suitable forage
 biomass at the macroplot location derived from the final fitted foodscape
 model 3.      **SAW_Summer_SuitableBiomass_Macroplots.xlsx** – Values of
 covariates included in the top model for predicting suitable biomass in
 the Sawtooth elk zone during summer (June 1 – July 31). XCOORD = X
 coordinate of the macroplot (UTM) YCOORD = Y coordinate of the macroplot
 (UTM) PrevMnSWE = Previous month’s snow water equivalent in cm, derived
 from Snotel sinAspect = Sine of aspect (a measure of eastness)  Elevation
 = Elevation at the macroplot location CanCov = Percent canopy cover
 derived from LandFire TotalBiomass = Total measured biomass of all forage
 plants in grams Predicted_SuitableBiomass = Suitable forage biomass
 estimated using the FRESH model SuitableBiomass (Kg/ha) = Estimated values
 of suitable forage biomass from previous column converted to kg/ha
 Predicted_SuitableBiomass (Kg/ha) = Predicted values of suitable forage
 biomass at the macroplot location derived from the final fitted foodscape
 model 4.      **SAW_Fall_SuitableBiomass_Macroplots.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Sawtooth elk zone during fall (August 1 – September 31).  XCOORD = X
 coordinate of the macroplot (UTM) YCOORD = Y coordinate of the macroplot
 (UTM) AprilSWE = April snow water equivalent in cm from nearest Snotel
 site PVT = Potential Vegetation Type derived from LandFire SeralStage =
 Early (ES) or late (LS) stage of succession EVI = Values of the Enhanced
 Vegetation Index derived from Modis CanCov = Percent canopy cover derived
 from LandFire TotalBiomass = Total measured biomass of all forage plants
 in grams Predicted_SuitableBiomass = Suitable forage biomass estimated
 using the FRESH model SuitableBiomass (Kg/ha) = Estimated values of
 suitable forage biomass from previous column converted to kg/ha
 Predicted_SuitableBiomass (Kg/ha) = Predicted values of suitable forage
 biomass at the macroplot location derived from the final fitted foodscape
 model 5.      **SFORK_Summer_SuitableBiomass_Macroplots.xlsx** – Values of
 covariates included in the top model for predicting suitable biomass in
 the South Fork elk zone during summer (June 1 – July 31).  YCOORD = Y
 coordinate of the macroplot (decimal degrees) XCOORD = X coordinate of the
 macroplot (decimal degrees) MnPrecip = Monthly precipitation in cm derived
 from PRISM cosAspect = Cosine of aspect (a measure of northness)    EVI2 =
 Values of the Enhanced Vegetation Index derived from Modis, squared CanCov
 = Percent canopy cover derived from LandFire TotalBiomass = Total measured
 biomass of all forage plants in grams Predicted_SuitableBiomass = Suitable
 forage biomass estimated using the FRESH model SuitableBiomass (Kg/ha) =
 Estimated values of suitable forage biomass from previous column converted
 to kg/ha Predicted_SuitableBiomass (Kg/ha) = Predicted values of suitable
 forage biomass at the macroplot location derived from the final fitted
 foodscape model 6.      **SFORK_Fall_SuitableBiomass_Macroplots.xlsx** –
 Values of covariates included in the top model for predicting suitable
 biomass in the South Fork elk zone during fall (August 1 – September 31). 
 YCOORD = Y coordinate of the macroplot (decimal degrees) XCOORD = X
 coordinate of the macroplot (decimal degrees) PVT = Potential Vegetation
 Type derived from LandFire cosAspect = Cosine of aspect (a measure of
 northness)    Elevation2 = Elevation at the macroplot location, squared
 CanCov = Percent canopy cover derived from LandFire TotalBiomass = Total
 measured biomass of all forage plants in grams Predicted_SuitableBiomass =
 Suitable forage biomass estimated using the FRESH model SuitableBiomass
 (Kg/ha) = Estimated values of suitable forage biomass from previous column
 converted to kg/ha Predicted_SuitableBiomass (Kg/ha) = Predicted values of
 suitable forage biomass at the macroplot location derived from the final
 fitted foodscape model 7.     
 **DC_Summer_Predicted_SuitableBiomass_Elk.xlsx** – Values of covariates
 included in the top model for predicting suitable biomass in the Diamond
 Creek elk zone during summer (June 1 – July 31) at elk GPS locations. 
 Animal_ID = Unique ID for each GPS-collared elk Fix_Date = Date that each
 GPS location was obtained PVT = Potential Vegetation Type derived from
 LandFire EVI = Values of the Enhanced Vegetation Index derived from Modis
 CanCov = Percent canopy cover derived from LandFire Elevation2 = Elevation
 at the GPS location, squared AprilSWE = April snow water equivalent in cm
 from nearest Snotel site   cosAspect = Cosine of aspect (a measure of
 northness)    Predicted_SuitableBiomass = Predicted values of suitable
 forage biomass at the GPS location derived from the final fitted foodscape
 model 8.      **DC_Fall_Predicted_SuitableBiomass_Elk.xlsx** – Values of
 covariates included in the top model for predicting suitable biomass in
 the Diamond Creek elk zone during fall (August 1 – September 15) at elk
 GPS locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained PVT = Potential Vegetation Type
 derived from LandFire EVI2 = Values of the Enhanced Vegetation Index
 derived from Modis, squared MnPrecip = Monthly precipitation in cm derived
 from PRISM Elevation2 = Elevation at the GPS location, squared Slope =
 Percent slope at the GPS location Predicted_SuitableBiomass = Predicted
 values of suitable forage biomass at the GPS location derived from the
 final fitted foodscape model 9.     
 **SAW_Summer_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the Sawtooth elk zone during summer (June 1 – July 31) at elk GPS
 locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained CanCov = Percent canopy cover
 derived from LandFire PrevMnSWE = Previous month’s snow water equivalent
 in cm, derived from Snotel Elevation = Elevation at the GPS location  
 Aspect = Aspect (degrees) at the GPS location Predicted_SuitableBiomass =
 Predicted values of suitable forage biomass at the GPS location derived
 from the final fitted foodscape model 10. 
 **SAW_Fall_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of covariates
 included in the top model for predicting suitable biomass in the Sawtooth
 elk zone during fall (August 1 – September 15) at elk GPS locations. 
 Animal_ID = Unique ID for each GPS-collared elk Fix_Date = Date that each
 GPS location was obtained CanCov = Percent canopy cover derived from
 LandFire EVI = Values of the Enhanced Vegetation Index derived from Modis
 PVT = Potential Vegetation Type derived from LandFire AprilSWE = April
 snow water equivalent in cm from nearest Snotel site SeralStage = Early
 (ES) or late (LS) stage of succession Predicted_SuitableBiomass =
 Predicted values of suitable forage biomass at the GPS location derived
 from the final fitted foodscape model 11. 
 **SFORK_Summer_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the South Fork elk zone during summer (June 1 – July 31) at elk GPS
 locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained CanCov = Percent canopy cover
 derived from LandFire EVI2 = Values of the Enhanced Vegetation Index
 derived from Modis, squared MnPrecip = Monthly precipitation in cm derived
 from PRISM cosAspect = Cosine of aspect (a measure of northness)
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the GPS location derived from the final fitted foodscape model 12. 
 **SFORK_Fall_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the South Fork elk zone during fall (August 1 – September 15) at elk GPS
 locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained CanCov, Elevation2 = Elevation at
 the GPS location, squared PVT = Potential Vegetation Type derived from
 LandFire cosAspect = Cosine of aspect (a measure of northness)    
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the GPS location derived from the final fitted foodscape model 13. 
 **Beaverhead_Summer_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the Beaverhead elk zone during summer (June 1 – July 31) at elk GPS
 locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained CanCov PVT = Potential Vegetation
 Type derived from LandFire CanCov = Percent canopy cover derived from
 LandFire Elevation = Elevation at the GPS location Aspect = Aspect (in
 degrees) at the GPS location PrevMnSWE = Previous month’s snow water
 equivalent in cm, derived from Snotel Predicted_SuitableBiomass =
 Predicted values of suitable forage biomass at the GPS location derived
 from the final fitted foodscape model 14. 
 **Beaverhead_Fall_Predicted_SuitableBiomass_Elk.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the Beaverhead elk zone during fall (August 1 – September 15) at elk GPS
 locations.  Animal_ID = Unique ID for each GPS-collared elk Fix_Date =
 Date that each GPS location was obtained CanCov EVI = Values of the
 Enhanced Vegetation Index derived from Modis PVT = Potential Vegetation
 Type derived from LandFire CanCov = Percent canopy cover derived from
 LandFire AprilSWE = April snow water equivalent in cm from nearest Snotel
 site SeralStage = Early (ES) or late (LS) stage of succession
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the GPS location derived from the final fitted foodscape model 15. 
 **DC_Summer_Predicted_SuitableBiomass_Randoms.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the Diamond Creek elk zone during summer (June 1 – July 31) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire CanCov = Percent
 canopy cover derived from LandFire Aspect = Aspect (in degrees) at the
 random location Elevation2 = Elevation at the GPS location, squared EVI =
 Values of the Enhanced Vegetation Index derived from Modis AprilSWE =
 April snow water equivalent in cm from nearest Snotel site   
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 16. 
 **DC_Fall_Predicted_SuitableBiomass_Randoms.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the Diamond Creek elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire Elevation2 =
 Elevation at the random location, squared Slope = Slope at the random
 location MnPrecip = Monthly precipitation in cm derived from PRISM EVI2 =
 Values of the Enhanced Vegetation Index derived from Modis, squared
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 17. 
 **SAW_Summer_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Sawtooth elk zone during summer (June 1 – July 31) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 CanCov = Percent canopy cover derived from LandFire Elevation = Elevation
 at the random location   Aspect = Aspect at the random location   
 PrevMnSWE = Previous month’s snow water equivalent in cm, derived from
 Snotel Predicted_SuitableBiomass = Predicted values of suitable forage
 biomass at the random location derived from the final fitted foodscape
 model 18.  **SAW_Fall_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Sawtooth elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 CanCov = Percent canopy cover derived from LandFire PVT = Potential
 Vegetation Type derived from LandFire SeralStage = Early (ES) or late (LS)
 stage of succession AprilSWE = April snow water equivalent in cm from
 nearest Snotel site EVI = Values of the Enhanced Vegetation Index derived
 from Modis Predicted_SuitableBiomass = Predicted values of suitable forage
 biomass at the random location derived from the final fitted foodscape
 model 19.  **SFORK_Summer_Predicted_SuitableBiomass_Randoms.xlsx** **-**
 Values of covariates included in the top model for predicting suitable
 biomass in the South Fork elk zone during summer (June 1 – July 31) at
 random locations.  XCOORD = X coordinate of the random location (decimal
 degrees) YCOORD = Y coordinate of the random location (decimal degrees)
 Year = Year CanCov = Percent canopy cover derived from LandFire cosAspect
 = Cosine of aspect (a measure of northness) MnPrecip = Monthly
 precipitation in cm derived from PRISM EVI2 = Values of the Enhanced
 Vegetation Index derived from Modis, squared Predicted_SuitableBiomass =
 Predicted values of suitable forage biomass at the random location derived
 from the final fitted foodscape model 20. 
 **SFORK_Fall_Predicted_SuitableBiomass_Randoms.xlsx** **-** Values of
 covariates included in the top model for predicting suitable biomass in
 the South Fork elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 CanCov = Percent canopy cover derived from LandFire Elevation2 = Elevation
 at the random location, squared cosAspect = Cosine of aspect (a measure of
 northness)     PVT = Potential Vegetation Type derived from LandFire
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 21. 
 **Beaverhead_Summer_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Beaverhead elk zone during summer (June 1 – July 31) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 CanCov = Percent canopy cover derived from LandFire PVT = Potential
 Vegetation Type derived from LandFire Elevation = Elevation at the random
 location sinAspect = Sine of aspect (a measure of eastness)  PrevMnSWE =
 Previous month’s snow water equivalent in cm, derived from Snotel
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 22. 
 **Beaverhead_Fall_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Beaverhead elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire CanCov = Percent
 canopy cover derived from LandFire SeralStage = Early (ES) or late (LS)
 stage of succession EVI = Values of the Enhanced Vegetation Index derived
 from Modis AprilSWE = April snow water equivalent in cm from nearest
 Snotel site Predicted_SuitableBiomass = Predicted values of suitable
 forage biomass at the random location derived from the final fitted
 foodscape model 23. 
 **Salmon_Summer_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Salmon elk zone during summer (June 1 – July 31) at random locations. 
 XCOORD = X coordinate of the random location (decimal degrees) YCOORD = Y
 coordinate of the random location (decimal degrees) Year = Year PVT =
 Potential Vegetation Type derived from LandFire Elevation = Elevation at
 the random location sinAspect = Sine of aspect (a measure of eastness)   
 CanCov = Percent canopy cover derived from LandFire EVI = Values of the
 Enhanced Vegetation Index derived from Modis PrevMnSWE = Previous month’s
 snow water equivalent in cm, derived from Snotel Predicted_SuitableBiomass
 = Predicted values of suitable forage biomass at the random location
 derived from the final fitted foodscape model 24. 
 **Salmon_Fall_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Salmon elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire SeralStage = Early
 (ES) or late (LS) stage of succession CanCov = Percent canopy cover
 derived from LandFire EVI = Values of the Enhanced Vegetation Index
 derived from Modis AprilSWE = April snow water equivalent in cm from
 nearest Snotel site Predicted_SuitableBiomass = Predicted values of
 suitable forage biomass at the random location derived from the final
 fitted foodscape model 25. 
 **Lemhi_Summer_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Lemhi elk zone during summer (June 1 – July 31) at random locations. 
 XCOORD = X coordinate of the random location (decimal degrees) YCOORD = Y
 coordinate of the random location (decimal degrees) Year = Year PVT =
 Potential Vegetation Type derived from LandFire CanCov = Percent canopy
 cover derived from LandFire Elevation = Elevation at the random location
 sinAspect = Sine of aspect (a measure of eastness)    PrevMnSWE = Previous
 month’s snow water equivalent in cm, derived from Snotel
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 26. 
 **Lemhi_Fall_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Lemhi elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire CanCov = Percent
 canopy cover derived from LandFire SeralStage = Early (ES) or late (LS)
 stage of succession EVI = Values of the Enhanced Vegetation Index derived
 from Modis AprilSWE = April snow water equivalent in cm from nearest
 Snotel site Predicted_SuitableBiomass = Predicted values of suitable
 forage biomass at the random location derived from the final fitted
 foodscape model 27. 
 **Teton_Summer_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Teton elk zone during summer (June 1 – July 31) at random locations. 
 XCOORD = X coordinate of the random location (decimal degrees) YCOORD = Y
 coordinate of the random location (decimal degrees) Year = Year PVT =
 Potential Vegetation Type derived from LandFire CanCov = Percent canopy
 cover derived from LandFire Elevation2 = Elevation at the random location,
 squared cosAspect = Cosine of aspect (a measure of northness)  EVI =
 Values of the Enhanced Vegetation Index derived from Modis AprilSWE =
 April snow water equivalent in cm from nearest Snotel site
 Predicted_SuitableBiomass = Predicted values of suitable forage biomass at
 the random location derived from the final fitted foodscape model 28. 
 **Teton_Fall_Predicted_SuitableBiomass_Randoms.xlsx** - Values of
 covariates included in the top model for predicting suitable biomass in
 the Teton elk zone during fall (August 1 – September 15) at random
 locations.  XCOORD = X coordinate of the random location (decimal degrees)
 YCOORD = Y coordinate of the random location (decimal degrees) Year = Year
 PVT = Potential Vegetation Type derived from LandFire Elevation2 =
 Elevation at the random location, squared Slope = Elevation at the random
 location in degrees MnPrecip = Monthly precipitation in cm derived from
 PRISM EVI2 = Values of the Enhanced Vegetation Index derived from Modis,
 squared Predicted_SuitableBiomass = Predicted values of suitable forage
 biomass at the random location derived from the final fitted foodscape
 model 29.  **DC_FRESH_input.xlsx** – Input data for the FRESH model
 collected in the Diamond Creek elk zone.  The spreadsheet contains two
 separate worksheets. Worksheet 1 includes the plant species-specific
 biomass and nutritional quality data from each sampled plot: Spp = Plant
 species and part (species codes are given in Data Table 1, included in
 this Dryad package, file 34 below) Plot = Unique plot ID where plant
 samples were collected Biomass = Dry biomass of sampled plant material in
 grams) DE = Digestible energy contenct DP = Digestible protein content
 DE.SD = Standard deviation of digestible energy DP.SD = Standard deviation
 of digestible protein Max = Percentage of time that species was allowed to
 be selected for by elk when it was available Worksheet 2 includes the
 nutritional requirements used as the basis for calculating suitable forage
 biomass: MEReq = Metabolic requirements for an adult lactating female elk
 DEConst = Digestible energy threshold for a lactating adult cow elk (kJ/g
 of forage) DPConst = Digestible protein threshold for a lactating adult
 female elk (g/100 g of forage) DMIConst = Estimated rate of dry-matter
 intake (g/d) 30.  **SAW_FRESH_input.xlsx** – Input data for the FRESH
 model collected in the Sawtooth elk zone.  The spreadsheet contains two
 separate worksheets. Worksheet 1 includes the plant species-specific
 biomass and nutritional quality data from each sampled plot: Spp = Plant
 species and part (species codes are given in Data Table 1, included in
 this Dryad package, file 34 below) Plot = Unique plot ID where plant
 samples were collected Biomass = Dry biomass of sampled plant material in
 grams) DE = Digestible energy contenct DP = Digestible protein content
 DE.SD = Standard deviation of digestible energy DP.SD = Standard deviation
 of digestible protein Max = Percentage of time that species was allowed to
 be selected for by elk when it was available Worksheet 2 includes the
 nutritional requirements used as the basis for calculating suitable forage
 biomass: MEReq = Metabolic requirements for an adult lactating female elk
 DEConst = Digestible energy threshold for a lactating adult cow elk (kJ/g
 of forage) DPConst = Digestible protein threshold for a lactating adult
 female elk (g/100 g of forage) DMIConst = Estimated rate of dry-matter
 intake (g/d) 31.  **SFORK_FRESH_input.xlsx** – Input data for the FRESH
 model collected in the South Fork elk zone.  The spreadsheet contains two
 separate worksheets. Worksheet 1 includes the plant species-specific
 biomass and nutritional quality data from each sampled plot: Spp = Plant
 species and part (species codes are given in Data Table 1, included in
 this Dryad package, file 34 below) Plot = Unique plot ID where plant
 samples were collected Biomass = Dry biomass of sampled plant material in
 grams) DE = Digestible energy contenct DP = Digestible protein content
 DE.SD = Standard deviation of digestible energy DP.SD = Standard deviation
 of digestible protein Max = Percentage of time that species was allowed to
 be selected for by elk when it was available Worksheet 2 includes the
 nutritional requirements used as the basis for calculating suitable forage
 biomass: MEReq = Metabolic requirements for an adult lactating female elk
 DEConst = Digestible energy threshold for a lactating adult cow elk (kJ/g
 of forage) DPConst = Digestible protein threshold for a lactating adult
 female elk (g/100 g of forage) DMIConst = Estimated rate of dry-matter
 intake (g/d) 32.  **Pregnancy_Analysis_Sheet.xlsx** – Pregnancy rates and
 corresponding descriptive statistics of suitable forage biomass at used
 and random locations for each elk zone and year.   Zone = Elk zone
 HabitatUse Year = Indicates years in which GPS collar data were (year
 shown) or were not (‘no collar’) available in each elk zone Pregnancy Year
 = Indicates year in which pregnancy rate was estimated for each elk zone
 Pregnancy_Rate = Estimated pregnancy rate (%) n (Pregnancy) = Sample size
 used to calculate pregnancy rate in each elk zone and year Summer_Mean_Elk
 = Mean value of suitable forage biomass at elk GPS locations during summer
 in each elk zone and year Summer_Median_Elk = Median value of suitable
 forage biomass at elk GPS locations during summer in each elk zone and
 year Summer_CV_Elk = Coefficient of variation of suitable forage biomass
 at elk GPS locations during summer in each elk zone and year
 Summer_Max_Elk = Maximum value of suitable forage biomass at elk GPS
 locations during summer in each elk zone and year Summer_Q.25 = First
 quartile of suitable forage biomass at elk GPS locations during summer in
 each elk zone and year Summer_Q.75 = Third quartile of suitable forage
 biomass at elk GPS locations during summer in each elk zone and year
 Fall_Mean_Elk = Mean value of suitable forage biomass at elk GPS locations
 during fall in each elk zone and year Fall_CV_Elk = Coefficient of
 variation of suitable forage biomass at elk GPS locations during fall in
 each elk zone and year Fall_Max_Elk = Maximum value of suitable forage
 biomass at elk GPS locations during fall in each elk zone and year
 Fall_Median_Elk = Median value of suitable forage biomass at elk GPS
 locations during fall in each elk zone and year Fall_Q.25_Elk = First
 quartile of suitable forage biomass at elk GPS locations during fall in
 each elk zone and year   Fall_Q.75_Elk = Third quartile of suitable forage
 biomass at elk GPS locations during fall in each elk zone and year  
 Summer_Mean_SB_Random_Locs = Mean value of suitable forage biomass at
 random locations during summer in each elk zone and year
 Summer_Median_SB_Random_Locs = Median value of suitable forage biomass at
 random locations during summer in each elk zone and year
 Summer_CV_SB_Random_Locs = Coefficient of variation of suitable forage
 biomass at random locations during summer in each elk zone and year
 Summer_Max_SB \_Random = Maximum value of suitable forage biomass at
 random locations during summer in each elk zone and year
 Summer_Q1_SB_Random = First quartile of suitable forage biomass at random
 locations during summer in each elk zone and year Summer_Q3_SB_Random =
 Third quartile of suitable forage biomass at random locations during
 summer in each elk zone and year Fall_Mean_SB_Random_Locs = Mean value of
 suitable forage biomass at random locations during fall in each elk zone
 and year Fall_Median_SB_Random_Locs = Median value of suitable forage
 biomass at random locations during fall in each elk zone and year
 Fall_CV_SB_Random_Locs = Coefficient of variation of suitable forage
 biomass at random locations during fall in each elk zone and year
 Fall_Max_SB_Random_Locs = Maximum value of suitable forage biomass at elk
 random locations during fall in each elk zone and year Fall_Q1_SB_Random =
 First quartile of suitable forage biomass at random locations during fall
 in each elk zone and year Fall_Q3_SB_Random = Third quartile of suitable
 forage biomass at random locations during fall in each elk zone and year
 33.  **Elk_MCP_shapefiles.zip** – Minimum convex polygons calculated from
 GPS-collar data in each elk zone. Random locations were distributed within
 these MCPs. 34.  **Extra_Tables.docx** – Additional tables not included
 with the published manuscript and supplementary material. Table 1: List of
 plant species sampled during our study and associated level of selection
 by elk Table 2: Species-specific linear regressions of p1ant biomass
 against plant cover (%), tree canopy cover (%), sample date, and
 interactions between plant cover and tree canopy cover and/or plant cover
 and sample date