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I want to find the highest value within a specific area of a shapefile feature class but am unsure about how to do this.
From the attatched image, I want to find the pixel within the outlined region with the highest value for fishing intensity (where the darker the rectangle, the higher the fishing intensity).
The background is a series of averaged point pixels rather than a raster layer
If you have access to the Spatial Analyst extension, you can use the Zonal tools to extract the value of the maximum fishing intensity value found within a given area (or many different areas).
For example, the Zonal Statistics As Table will give you a table as output with all the maximum values found in a raster layer based on zones defined on another raster or polygonal layer calleed the "zonal layer".
If you however need to find the exact location of the maximum pixel within a specified area you could (Spatial Analyst extension still needed):
use the Raster Calculator to extract the exact maximum pixel within the specified zone with an expression like the following
Con("FISHING_RASTER" == "MAX_RASTER", "FISHING_RASTER")
This way you would extract only those pixels with the maximum value of fishing intensity from your original raster according to your area.
If your aim is only find the highest value on a pecified area and only once in a while, you could simply clip the raster with your polygon layer (Clip tool), and then have a look at the statistics of it to find the maximum (and other interesting statistics values). Try using the Calculate Statistics tool to calculate the statistics if they are not included in the clipped raster. You can see them in the layer properties, Source page.
