1. Living the Life of a Trout!
Tracking a Trout’s Life Cycle

2. What is a life cycle?
Biological (& continuous) process that all organisms undergo
Period of time where an organism is produced, grows, and becomes sexually mature and reproduces
Consists of various defined stages in the growth and development of an organism

3. Every organism has a life cycle!

4. Trout Term used to describe a variety of freshwater fish
Play an important role in the ecosystem
Source of food and nutrition
Trout common to NJ:
Rainbow, Brook, & Brown
Brown Bear w/ Salmon

5. Salvelinus fontinalis
Brook Trout
Salvelinus fontinalis

6. Trout Life Cycle
Fry
Alevin
Fingerling
Eggs
Juvenile
Mature Adult

7. Spawning
Biological process used by a majority of fish and aquatic creatures to reproduce
Requires sexually mature trout (~3 yrs old) to release eggs and sperm
Egg and sperm are reproductive cells
Also known as gametes

8. The REDD A female ready to mate will build a nest called a redd
Uses fins to remove gravel & debris from the bottom of a lake or stream
Usually a shady location
Location where the eggs will begin to grow and development.
The REDD

9. Stage 1: Eggs Female releases her eggs into the redd’
Male releases milt (sperm) to fertilize the eggs
Afterwards, the female covers the eggs with gravel
Female will move to a different location to create another redd and mate with another male
In a hatchery, eggs are removed from the female to be fertilized

10. Egg Development Undergo process of ‘hardening’
Occurs within 1 hour after fertilization
All pores on the egg are closed and sealed
Makes eggs sticky
After ~20 days, eye spots develop in the embryo

11. Eye Spot
Developing
Body
Fertilized Egg

12. Alevins
After the eggs hatch (approximately 2-3 weeks), trout are classified as alevins
Remain attached to the yolk sac at their belly
Yolk sac provides nutrition
Continue living in the redd

13. November 1, 2013
Recently hatched trout!

14. November 25, 2013
Eventually, the alevins deplete their yolk sacs. At this point, they begin swimming to the surface of the tank to look for food. Once the yolk sacs are completely depleted, the fish are independent and move into the next stage of life.

15. Fry Trout are independent of the yolk sac and begin looking for food
No more yolk sac: Actually look like fish!
Yolk sac

16. November 27, 2013
The trout are released from the net and the Styrofoam is removed from the front.
Only the trout independent of their yolk sacs swim throughout the tank (all others line the bottom).

17. December 9, 2013
All the fish congregated at the top of the tank are looking for food since they no longer have a yolk sac
Digital Thermometer

18. Lookin’ like Brook trout!

20. April 28, 2014: Release day

21. Trout released into the stream bed

22. We made the paper!

23. Mature Trout Trout will move to the main current of the stream
Feed primarily on insects
For the next three years, the trout will continue to grow and develop until reaching sexual maturity
Then the life cycle continues…