NEVADA DEPARTMENT OF WILDLIFE TROUT IN THE CLASSROOM NEVADA DEPARTMENT OF WILDLIFE MASON VALLEY HATCHERY Yerington , Nevada

MASON VALLEY HATCHERY OUR HATCHERY The hatchery began construction in 1988 and opened for production in 1990 at a cost of 8.1 million dollars with an annual cost of operation of $455,000 on average. That breaks down to $2.00 per pound of fish, and .50cents per fish. The funding for this hatchery came from sales from the Verdi hatchery, trout stamp sales, and federal matching funds. The Hatchery Crew This is a full functioning facility, meaning we raise the fish from egg to liberation. The hatchery has a crew of 5 employees: Supervisor Assistant Supervisor 3 Technicians The technicians are given areas of responsibility throughout the hatchery.

MASON VALLEY HATCHERY The primary species raised Pyramid Lake Cutthroat Trout Independence Cutthroat Trout (Heenan Lake, California) Sheep Creek Brown Trout (Gallagher Hatchery, Nevada) Tasmanian Rainbow Trout ( Gallagher Hatchery, Nevada) Eagle Lake Rainbow Trout ( Tenn. Or Montana NFH system) Erwin Rainbow Trout ( Tenn. Or Montana NFH system) Tahoe Rainbow Trout ( Marlette Lake, Lake Tahoe Nevada)

MASON VALLEY HATCHERY Our planting location around the state range from the upper most North West corner to Walker Lake.

MASON VALLEY HATCHERY

MASON VALLEY HATCHERY

MASON VALLEY HATCHERY

MASON VALLEY HATCHERY

TROUT IN THE CLASSROOM

Rainbow trout egg Daily Temperature Units (DTU’s) TROUT IN THE CLASSROOM Rainbow trout egg Daily Temperature Units (DTU’s) A Daily Temperature Unit (DTU) is defined as: Every 1°F above freezing (32°F) for a 24-hour period. - EXAMPLE: If the water temperature for a 24-hour period stays constant at 50°F, it would contribute 18 DTU’s. (50-32=18) - EXAMPLE: If the water temperature for a 24-hour period fluctuated from 48°F for 12-hours, and 50°F for another 12-hours this would contribute 17 DTU’s. (48-32)/(2)=8 + (50-32)/(2)=9 8+9=17 Don’t worry about minor temperature differences, for our purposes it is not that critical.

TROUT IN THE CLASSROOM When will they hatch?

TROUT IN THE CLASSROOM Water Temperature 35 °F 40 °F 45 °F 50 °F 55 °F Rainbow Trout Days to hatch - 80 48 31 24 DTU’s 640 624 558 552 Brown Trout 156 100 64 41 468 800 832 738

TROUT IN THE CLASSROOM FACTORS EFFECTING EGG DEVELOPMENT LIGHT -Direct sunlight or UV light will effect the development of the eggs. -The optimal thing to do is minimize there light exposure.

TROUT IN THE CLASSROOM TEMPERATURE -Fluctuation for developing eggs is a good thing within range. 2°F to 3°F is an optimal temperature variation.

TROUT IN THE CLASSROOM OXYGEN - The best condition for optimal egg development is at or near 100% saturation. To much Oxygen will cause gas bubble disease. This is not a concern due to the systems we are using.

Cutthroat Trout Eggs Eyed eggs 22 days old @ 47 Degrees F

Cutthroat Trout Alevin(sac fry) 35 days old @ 47 degrees F

Cutthroat Trout Sac Fry Sac Fry in late development 44days @ 47 Degrees F

Cutthroat Trout Fry Fry 55 days @ 47 Degrees F