Factsheet # 6
REMOTE SENSING & GEOSPATIAL ANALYSIS LABORATORY
Precision Forestry Cooperative, College of Forest Resources
Spatiotemporal analysis of mountain goat habitat
Understanding multiscale dynamics of landscape change through the application of remote sensing & GIS
GPS animal movement data assessed in combination with Moderate Resolution
Spectroradiometer [MODIS] derived Enhanced Vegetation Index [EVI] data provides a brief
snapshot in time of the landscape. An example of the MOD13Q1 product is at MODIS Level 3‐
16‐day composite EVI at a 250m resolution is shown in this factsheet. A green‐brown linear
color table was applied to the data set for contrast emphasis. The data of one MODIS scene
covers an extensive swath of the Pacific Northwest, a homerange boundary was used to
subsample the MODIS scene to a smaller sub scene for this research.
The MODIS EVI measures the amount of vegetation present on the ground via examination of
the red (620‐670 nm), near‐infrared (841‐876 nm), and blue (459‐479nm) reflectance bands.
The images enhance the vegetation signal and the resulting measurement allows for a
precise inter‐comparison of spatial and temporal variations in terrestrial photosynthetic
activity on the landscape. Combining these images with the GPS derived animal movement
and overlaying the homerange polygon allows for the examination of the abundance and
availability of vegetation that mountain goats are utilizing. Going one step further and
examining the intra‐annual variation of habitat usage could help identify a vegetative
predictor variable that to assess current extent of habitat across its entire range as well as;
assessing any declines in habitat based upon historic conditions.
Sep 14‐
S 14‐Sep Sep 14
S 29
Sep 29 2006
29 2006
2006
Sep 29‐
Sep 29‐
Sep 29
29‐Oct Oct 15
Oct 15 2006
15 2006
2006
Spatiotemporal analysis of the GPS data results in the intra‐annual establishment of the home range polygons in bi‐weekly cycles. Oct 16‐‐Octo Oct 16
Octo 31 2006
31 2006
Nov 1‐‐Nov Nov 1
Nov 16 2006
16 2006
A digital elevation model [DEM] allows for the extraction of topographic data for all data.
•
•
•
•
•
•
Import GPS collar data to coincide with MODIS tiles
Calculate Minimum Convex Polygons for each tile
Calculate centroid for each Polygon
Extract MODIS EVI indices for each centroid
Extract elevation data for each centroid
Combine GIS and MODIS data and export to EXCEL
The MOD13Q1 product is a sample of the MODIS Level 3‐16‐day composite EVI at a 250m resolution. A green‐brown linear color table was applied to the data set for contrast emphasis. Nov 17‐‐Dec Nov 17
Dec 2 2006
2 2006
Applications
The vegetation phenology will assist in identifying the preferred range of available habitat in their known habitat use areas. Applying this
variable to the remaining landscape as a habitat predictor variable will enable the assessment of current and historic habitat conditions;
noting any fluctuations that could assist in assessing species decline.
Time Serries
0.0
0.1
Aug29‐Sep29‐06
Nov01‐Nov16‐06
Dec19 Jan03 07
Dec19‐Jan03‐07
Feb02‐Feb17‐07
Mar22‐Apr06‐07
May09‐May24‐07
Jun26‐July11‐07
Aug13‐Aug28‐07
Measure of indices: Intra‐annual Home Range Polygon 0.2
0.3
EVI
The combination of assessments of the time series home
range polygons provides a snapshot in time of the amount
and quality of vegetation available with the EVI index
showing the lush vegetation from 0.2 to 0.6 being available
and the times of year that it is utilized. This can be seen in
h images
i
h right
i h side
id off this
hi factsheet.
f
h
Th data
d
on the
The
the
series provides insight into intra‐annual home range
movements and a brief glimpse of the current available
habitat that can be compared with previous years to
highlight any decline in total available habitat. This is
accomplished through the development of a habitat EVI
predictor variable gained from the first years’ data. This
predictor variable can be used to define total available
habitat in other regions of the state.
THE ISSUE: A reduction in available habitat could be a major factor in the reduction of Mountain goat populations within Washington State. IMODIS time series analysis of mountain goat intra‐annual movements can be assessed in combination with GPS derived bi‐monthly home range polygons to examine the links between habitat usage and vegetation indices. EVI extraction from the MODIS used to identify a habitat predictor variable that is correlated with their home range use. Application of this knowledge will assist in determining the fluctuations in current available habitat and/or declining habitat conditions across the entire range of available habitat.
Dec 3‐‐Dec Dec 3
Dec 18 2006
18 2006
Time series EVI Indices and homerange for one annual cycle.
THE KEY QUESTIONS:
Can EVI be used as a predictor variable to assess mountain goat habitat?
Citation: James, L., L. M. Moskal, 2008. Spatiotemporal Analysis of Mountain Goat Habitat. Factsheet # 6. Remote Sensing and Geospatial Application Laboratory, University of Washington, Seattle, WA. Digital version of the fact sheet can be downloaded at: http://dept.washington.edu/rsgal/
ⓒ RSGAL 2008