For what type of fish is the daily bag limit one landlocked salmon and one brook trout applicable?

The daily bag limit of one landlocked salmon and one brook trout applies specifically to rivers due to the regulations set for freshwater fishing in these environments. Generally, rivers are managed separately from lakes, streams, and brooks because of their unique ecosystems and flowing waters. These ecosystems can support different fishing regulations to ensure sustainable populations of fish species like landlocked salmon and brook trout.

In the context of the other choices, lakes often have differing regulations because of the larger water volume and different habitat characteristics, which can support larger fish populations. Streams and brooks, being smaller and potentially more delicate ecosystems, may have different limits or angling methods that cater to their size and fish population dynamics. Thus, the designation of rivers for this specific limit reflects the need to manage fish populations in their particular habitats effectively.