Lake Sockeye spawning - upstream of lake, max distance?

[smnorris]

Currently, for sockeye spawning upstream of rearing likes, the model in main is:

Suitable upstream segments were modeled as spawning habitat if they were directly connected to (rearing) lakes or to modeled Sockeye Salmon spawning segments (i.e., directly upstream of another spawning segment).

This constraint was mistake/mis-interpretion in the initial creation of the model.

As a preliminary fix for PSF, In branch psf, there is no constraint at all - any suitable stream upstream of a rearing lake is included as spawning habitat.

CWF (Nick L) provides this guidance for something in between:

So, I think using the maximum known upstream distance (so far it is 4.7 km) is appropriate for all Sockeye Salmon streams. This might mean that extra spawning habitat is identified in areas where fish rarely push past more suitable spawning habitat closer to spawning lakes, but even then there is some potential value in managing or reconnecting the additional habitat (e.g., it may be used in high abundance years). I am equally open to using a lower value if an analysis of maximum distances reveals outliers, but most observations are within X km of rearing lakes.

todo:

• confirm max known upstream distance
• make change in sockeye model