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SCGIS Hands-on Workshop: Introduction to GIS for Habitat Analysis and Home Range Estimation. Sadie Ryan, UC Berkeley. What is GIS?. Geographic Information System – object often uses software Geographic Information Science – discipline Blueprint of a house – simplest GIS
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SCGIS Hands-on Workshop: Introduction to GIS for Habitat Analysis and Home Range Estimation Sadie Ryan, UC Berkeley
What is GIS? • Geographic Information System – object • often uses software • Geographic Information Science – discipline • Blueprint of a house – simplest GIS • Important qualities: • Overlay operations • Map equations in layers • Spatial relationships • point to point • Ancillary data • data associated with locations • Points vs. Grids
Jargon • Geospatial/Georeferenced – spatial data that has been located in reference to a standard coordinate system for the Earth (e.g. longitude, latitude) • Projection – system for transforming a known location on the non-flat earth to a flat plane – this is extremely important for manipulation of areas – a circle drawn on a lat/long earth is not a circle, unless you make it infinitely small at the equator.
How do we collect spatial data? • Radio collars
How do we collect spatial data? • Direct observation and paper maps • Museum records of collection locations
How do we collect spatial data? • GPS • Collars/patches that upload • Handheld records of indicators • – scat, tracks • Remotely sensed data • Satellite imagery • Vegetation, landcover, climate • Aerial photgraphy • Radar etc.
How do we use spatial data? • Home ranges • Habitat selection • Biogeography questions
Home range methods • Traditional: Minimum Convex Polygon (MCP) • Join the outermost points together • Useful for delineating overall area used – useful for conservation and reserve design with sparse data • You can use just 95% of points to define error, but no clear selection method for it • Assumes animals are using the whole area equally
Home range methods • Kernel methods • Smoothing of points, predicts likelihood of occurrence, even beyond points • Shows areas of higher and lower densities – useful to define key areas like feeding grounds • Similar assumption of whole area use; no holes • Alarming property of increasing as you add data • Harmonic Mean • Accents areas of higher density • Similar to Kernel methods • Local convex hull method – LoCoH • More data needs newer methods (GPS data is huge) • Good for ID of non-use areas • Allows for physical barriers to movement Adaptive Kernel Harmonic mean
1 Buffalo Herd, 4085 locations in 2000 MCP Minimum Convex Polygon
1 Buffalo Herd, 4085 locations in 2000 Kernel Method 95% 50% Default Smoothing H
1 Buffalo Herd, 4085 locations in 2000 k-NNCH Nearest Neighbor Convex Hull (Getz & Wilmers, 2004) k=5 neighbors shown
1 Buffalo Herd, 4085 locations in 2000 k-NNCH Nearest Neighbor Convex Hull (Getz & Wilmers, 2004) k=20 neighbors shown
Habitat Selection methods • Points on a map • Points are then associated with location-specific data • e.g. vegetation type, distance from water, slope, elevation, aspect, soil type etc. • Many different statistical analyses of results • Demo of simple proportional occurrence • Buffalo and vegetation type, distance to water
Study Site Kruger National Park Klaserie Private Nature Reserve 1993-2000 3 herds
Selected type 2 and 5, and not 3 and 8 • A. nigrescens and Grewia sp.: open woodland • Mixed Acacia sp.: shrubveld • Mixed woodland • C. apiculatum, S. birrea: open woodland; • C. apiculatum, S. caffra, Grewia sp.: short woodland • C. apiculatum, C. mollis, Grewia sp.: closed short woodland • C. apiculatum, C. mopane: woodland • C. mopane: woodland and shrubveld Habitat Selection: Vegetation Type
Hawth’s tools is a free extension: www.spatialecology.com