Medicine & TechnologyScientists have found out the reason why Salmon migration is happening. It is because of the tidal and temperature changes that are happening in the water.
California's record-setting drought has dried up large swaths of the San Joaquin River; bad news for the state's salmon. So in a desperate effort to save a generation of hatchlings, tanker trucks are being employed to transport the young fish downstream. With their normal passage blocked, the fish are now migrating via Highway 99.