We provide ubiquitous assistance to(or of?) the ideal filling, constant monitoring and protection (of?) the spawning grounds. The future of salmon life depends (on)? this mission...


protection of the spawning grounds
depends on/upon this mission

It is possible that "with" would fit in the first place, but the sentence reads a bit oddly, especially the words "ubiquitous", "ideal", and, to some extent "constant". This would read OK:

We provide assistance with the filling, monitoring and protection of the spawning grounds.


Thanks for your explanation.