Eagle Lake Trout - Known for its resistance to highly alkaline waters, the Eagle Lake trout is a native to nearby Eagle Lake and its Pine Creek tributary. Due to diminishing flows into Pine Creek, a program was started in the 1950's to preserve the species. Once found only in its native waters, the Eagle Lake trout can now be found in many waters throughout the state. Egg production for Eagle Lake Trout reaches approximately 5 million triploid (PDF) eggs. Learn more about heritage trout.
Brown Trout - Originally from parts of Eastern Europe, the brown trout has been planted in this state for many years. A favorite of many anglers, the brown continues to be stocked in select waters despites its non-native heritage. Approximately three million triploid (PDF) eggs are produced every year at Mount Shasta.
Brook Trout - Originating from the Eastern United States, brook trout were brought over the rail lines in the early 1800's Despite their common name, the brook trout is actually a char. Brook trout are received from Crystal Lake Hatchery as eggs and catchable-size fish for stocking local waters. These triploid (PDF) brook trout are planted via air and truck into various northern California waters.
Rainbow Trout - This popular fish, native to the tributaries of the pacific ocean in North American and Asia, can now be found all over the world. Farmed as food in many areas, rainbow trout can now be found in South America, Europe, and the Middle East. Mount Shasta Hatchery currently raises 2 different strains of rainbow trout; Shasta and Coleman strains. Average egg take for the 2 rainbow trout strains is around 26 million eggs per year. Rainbow trout are provided for recreational angling are now sterile triploid (PDF).
Spawning takes place from the beginning of November to mid-march. Learn more about the triploid process (PDF).
Spawning
Beginning near Halloween, staff check fish for sexual maturity. For the next 5 months the crew will spawn fish as they become ripe. Fish are first moved into the spawning house where they are anesthetized for easier handling. Ripe fish are placed on the sorting table, where one by one they are air spawned. The air spawning method involves inserting a needle in the females's abdomen to create pressure, pushing the eggs out for fertilization with sperm (milt) collected from a male fish. Milt is collected separately and added to eggs collected in the hatchery building. After fertilization, eggs undergo the triploid (PDF) process and are then placed into vertical flow incubator stacks, where they will continue to develop into fish.

Air Spawning female trout

Fertilized eggs in incubator tray
After roughly 35 days the egg will develop eyes. At this point most eggs are shipped, or moved into a hatching jar.

Fertilized eggs in hatching jars
Thirty more days and fish will begin to hatch. These times vary with water temperature. Mount Shasta Hatchery has cold water and it takes longer for eggs to hatch into fish.
After hatch, fry develop in the hatchery troughs until they are large enough to either be stocked into approved backcountry waters by airplane or pack animal (horse or mule), or are raised to larger "catchable" size for truck stocking to local waters.

Fingerlings in hatchery troughs

Inventory by weight count
Fish Stocking
Rainbow trout (Shasta strain) and Eagle Lake trout are planted as fingerlings by air and mule, and as catchable-sized fish to roadside waters by truck.
Look up recent fish plants.
Every year approved lakes are stocked by air to waters inaccessible by vehicle.

Fish delivery to CDFW airplane

Historic photo of aerial stocking
During the spring and summer months Mount Shasta Hatchery stocks catchable trout in approved local waters by truck.

Loading a truck for stocking
In select places, pack animals or ATVs are used for fish stocking

Backcountry Horsemen often assist Mount Shasta Hatchery to stock high mountain lakes