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

2. 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.

3. 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)

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

6. MASON VALLEY HATCHERY

7. MASON VALLEY HATCHERY

8. MASON VALLEY HATCHERY

9. MASON VALLEY HATCHERY

10. TROUT IN THE CLASSROOM

11. 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.

12. TROUT IN THE CLASSROOM
When will they hatch?

13. 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

14. 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.

15. 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.

16. 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.

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

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

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

20. Cutthroat Trout Fry
Fry
55 days
@ 47 Degrees F