chinook salmon development
Chinook alevin
At this time of year we occasionally come across chinook alevin (or sac-fry) in our juvenile salmon outmigration monitoring, which typically runs from December to June. As mentioned in a recent post Halloween Treats, an alevin is a salmon that has broken free from the soft shell of the egg, but still retains a nutrient-rich yolk sac (shown in the photo above). The yolk sac provides nourishment to the alevin during its first 2-3 weeks after hatching. Usually, during this stage they will remain in the gravel, but occasionally strong currents wash them out. Once the yolk sac is absorbed Read More…