Students read a life cycle chart and gather information from the Internet to learn about salmon life cycles. The class creates a chart showing habitat requirements at each life stage.

Students will be able to:

• list, in order, each stage of the salmon and steelhead life cycle
• describe habitats fish use at each life stage
• explain other factors that influence survival of salmon

science, reading

• Salmon and Steelhead Life Cycle (print from this site)
• Internet connection and computer(s)
• Large piece of paper for making chart
• Ruler
• Felt pens
• Wall map ofPacific Northwest and/or California

Salmon and steelhead have always been an integral part of Pacific Northwest ecosystems and human social structures. In rivers and streams ranging from Alaska to California, these amazing fish migrate from their freshwater rearing grounds to the ocean, where they grow large on a rich supply of food. When they are mature, after 2 to 4 years roaming the open seas, they return to the stream of their birth to spawn a new generation and complete their own life cycle. Except for steelhead, all Pacific salmon species die soon after spawning, and the nutrients they gathered in the ocean are released into the stream as their bodies decay. In this way, salmon bring a valuable gift back to the stream - nourishment for an ecosystem where nutrients are constantly being washed away by flowing water. Salmon and steelhead are also a nourishing gift to humans.

When European settlers arrived in the Pacific Northwest, they thought the supply of salmon was boundless. However, as our population has grown, so has our demand for water. When systems were designed for delivering water to humans, the fish were not the highest priority. Dams constructed to store water and generate electricity became impassible barriers to migrating fish. In California's Central Valley, the available salmon habitat throughout the Sacramento and San Joaquin river systems has been reduced from 6,000 miles to only 300 miles. The impact on fish populations was dramatic.

Removing water from rivers for human use means there is less water available for the fish. As flows diminish and river levels drop, water temperatures tend to rise. Salmon and steelhead must have cold water to survive. The methods used for extracting the water can also harm fish. Diversion dams span the river and form barriers to migrating fish. Fish ladders and/or side channels for fish passage are often built, but they don't always work. Fry migrating downstream often swim into, or are drawn into diversions that take water directly from the river. Placing screens over diversions can eliminate this problem. Large dams that block much of a river's natural flow can profoundly alter fish habitat.

The Sacramento River is home to the endangered winter run chinook salmon. There are four separate runs of chinook salmon in the Sacramento, which means fish may be hatching, rearing or migrating up or down river at any time during the year. Since the winter run is listed as endangered, most of the water management strategies implemented are geared toward the survival of these fish.

Society has become concerned about the fate of salmon in the Sacramento River and other streams. With public support, laws, funding and multi-agency commitments addressing the issue of salmon survival, time will tell if present efforts can secure a long term future for these magnificent creatures.

• Starting from the NatureWater - Water and the Environment Resources page, review and printout the five Problems/Solutions pages, and visit the other web sites listed.
• Print the page titled Salmon & Steelhead Life Cycle, linked at the Resources page. Keep it as your master copy.
• Make an overhead transparency or make copies for students.
• Construct a chart with five columns, headed as shown below.
• Post for the students review all the on-line addresses for the web sites listed on the Resources page. The students can simply link from that page, also.

Column headings:

For this lesson, you will complete only the first three columns of the chart. Problems and solutions are the topic of the next lesson. The information is summarized below.