Salmon Anatomy

Salmon have evolved to be adapted to live in both freshwater and saltwater, to travel great distances, and to survive many challenges. We will get up close and personal with this amazing creature.

Through this assignment, you will ...

• Understand the anatomy of salmon and importance of salmon to NW Native Tribes

• Analyze how salmon otoliths are being used to study climate change

Part 1: Salmon Dissection

Materials:

• fish

• knife

• probe

• forecps

• gloves

• butcher paper

Dissection Procedure PowerPoint

Set Up: Move 2 tables together to create a work space. Spread out white butcher paper to cover the table. Lay out the tools. Create labeled areas on the butcher paper to place and then photograph the fish organs.

External Anatomy: Identify the external fish anatomy for the class. Read about external anatomy (link here: http://www.pskf.ca/sd/#ext)

Internal Anatomy: Walk the class through the steps of the dissection in order and identify internal parts throughout the dissection. It is very important that we go in the right order, so that we don't destroy internal organs before we have a chance to examine them. Read about the dissection procedure (link here: http://www.pskf.ca/sd/#int)

Otolith Dissection: Find, remove, and read about the otolith. Read "Removing Otoliths" and "Determining Age."

Clean-Up: Everyone is on the clean-up crew. We are responsible for proper disposal of fish and dissection materials and the clean-up of tools and work space.

Resources: 

• 20 Minute Salmon Dissection Video

• WDFW Salmon Dissection Guide

In your journal, respond to these questions:

1. Why do scientists dissect living organisms?

2. What do you think the benefits of a scientific dissection are?

3. What could be the drawbacks?

Part 2: First Salmon Ceremony

Read the "First Salmon Ceremony" reading from the "Elwha River and Its People" book.

After dissecting the fish, assemble its remains on cedar boughs to return to the Elwha River.

See photos from this lesson. 

Salmon Anatomy Extension: Seeing Climate Change through a Fish's Lens

One of the things we will be looking for when we dissect our fish is its otolith. Otoliths are small rocks that float in the fish's skull and are used for balance and hearing. Water temperature, age, and even stress are recorded on the otolith in the form of rings - just like on the rings of a tree.

Scientists use these rings to learn many things about the fish and its environment. Currently, ancient otolith fossils are being used to learn more about climate changes in the past and help us think about future climate change.

Check out this website about otoliths. 

See pictures of an otolith here.

Learn more about otoliths how scientists are using them to understand climate change by reading the article "Reading the Record in Fishes' Ears" from The New York Times Science Page.

In your journal, do the following:

• Describe how scientists are using otoliths to understand the history of climate change.