GEOG 310 Lecture Notes - Lecture 22: Sockeye Salmon, Swimming Upstream, Gillnetting
Document Summary
Example of survival through the salmon life cycle: fraser river sockeye salmon. Ocean range: pinks stay close to the shore, each different type of salmon have different morphologies and spend different amounts of time in their area. Salmon also return to where they were born to spawn: there are genetic difference between different spawning locations, conservation units: not breeding with each other, we try to conserve salmon in one area. Exploitation of pacific salmon in the pacific northwest: traditional methods: using nets to capture the fishes that are swimming upstream, contemporary method: Seining: big nets dropped into ocean and encircle fish. Gillnetting: nets strung across the channel, fish get stuck. Trolling: hook and line method to catch the fish. Pacific salmon life cycle: spawners: fish that swam upstream and laid eggs, juvenile: fish that stay in fresh water and early ocean, idea of how many adults" we can catch before they become spawners.