Corridor & Cost Path Analysis

The cost of movement is usually something thought of in terms of money, in the context of shipment or transport.  Cost can take the form of a whole host of other factors, though, when it refers to some expenditure to move across a landscape.  We can express cost in terms of time, energy required, or even impact on the environment.  Anything that effects movement can be modeled as a cost, which can also be translated into a predictive measure, as in the case of corridor modeling and analysis.

  
The above is a map of the results of a corridor model for black bear movement between two disconnected portions of a National Forest.  The placement of the corridor was chosen in terms of an analysis of the elevation, land cover, and distance from roads- with its final size and position determined by the preferred habitat of the black bear.  Each cost, or factor affecting the bears' possible movement, was given a weight, and the GIS output was a predictive corridor between the two protected areas.  Possible movement of something as unpredictable as a wild animal can never be definitively plotted, but expanding a possible path into a corridor, with placement based on measurable factors, can provide a useful predictive tool.