Linear referencing to calculate maximum distance between points by group along line (river system) using ArcGIS Pro

Question

I am using ArcGIS Pro.

I have a series of points representing animal locations that were tracked in a small stream. I would like to get the distance between the most upstream and downstream location for each individual (also known as the Linear Home Range), following the river path. Essentially the largest distance along this line between points, grouped by individual. I have downloaded a polylineZM file for the stream - and I understand that I can use Linear Referencing to get the distances between these points, and a measure of the point location in reference to the beginning of the line. But, I am looking for a little more than this, as this result gives me an output that I would need to manually manipulate to get my answer. If there is a code or workflow that would help me to easily calculate this without having to split the data set into a file for each individual, manually rerun it for each individual, sort output by the distance along the line and then manually subtract the largest and smallest points, that would be ideal.

The most recent point may not necessarily be the most upstream point, as the animals are not only traveling in one direction. Below is a screen grab of my points -

If there is a need to write an ArcPy script or a suggestion for manipulating the data after the Linear Referencing output file after it is created - I am all ears.

Answer 1

LR will calculate distances along separate river segments. To apply it you need "long" rivers starting at multiple upstream points, ending at outlet(s). If you are capable of producing geometric network you might use script from here, to calculate distances of network nodes to outlets and apply LR later.

Alternative to it is using raster approach, namely cost distance.

• populate new field in your streams table by value of 1
• convert them to raster (cost) using that field.
• derive both ends points for stream segments
• select outlet(s). Run cost distance using outlet(s) as sources
• Convert output raster to points:
• spatial join with your points will do the rest.

Note: in the picture above I labelled only some of the points. More accurate results can be obtained by using smaller cell size, but not overdo it, because your points are not perfect spatially.

After obtaining distances for all points, use summary statistics on animal I'd to compute Max and min of distance values.