Editing Directional selection (section)

=== Bears hunting sockeye salmon ===
[[File:Caviar drips out of pink sockeye salmon hunted by big brown bear (53161193868).jpg|thumb|Bear hunting sockeye salmon]]
Studies carried out in Little [[Togiak Lake]] in Alaska, indicate that bear [[predation]] has a significant impact on sockeye salmon populations, especially in shallow streams. Bears often focus on larger male salmon and tend to prefer those that have just arrived at the spawning grounds, particularly in smaller streams where they can catch them more easily. This predation may accelerate the aging of salmon by favoring later arrivals. Additionally, the impact of predation varies among different salmon populations based on their habitat and density; it tends to be more selective in areas where fish are readily accessible. While high levels of bear predation can occur, healthy salmon populations usually maintain strong reproductive potential, although the effects are more pronounced when populations are low. Overall, these dynamics illustrate how bear predation affects salmon behavior and life cycles, influencing their evolutionary processes.<ref name=":2" />