On the Trail of the Hudson's Migratory Fish
Educator Lesson Plan
Students will practice addition and subtraction skills by tracking the movements of migratory fish of the Hudson River estuary.
Objectives:
Students will solve word problems that require them to:
- add and subtract using data from tagged fish to calculate distance traveled, elapsed time, and growth;
- understand the life cycle of anadromous fish.
Grade level:
Elementary (Grades 3-5)
Subject Area:
Math, Geography, Science
Standards:
Mathematics, Science, & Technology Standards 3, 4
Skills:
-
- Use whole numbers to identify locations and measure distances.
- Add and subtract whole numbers.
- Apply mathematics in real world settings.
- Reason mathematically.
Vocabulary:
anadromous, brackish, estuary, migration, recapture, river mile, spawn, species
Duration:
Preparation time: 5 minutes
Activity time: 45 minutes
Materials:
Each student should have:
- Worksheet: On the Trail of the Hudson's Migratory Fish (180 kb pdf)
- Calendar (to determine number of days in each month)
- Hudson River Miles map (190 kb pdf) * Note: This file is designed to print on legal (8.5" x 14") paper; if legal paper is not available and selected in printer menu, it will default to letter size (8.5" x 11").
- Pencil
- If available, a wall map showing the Hudson and the eastern coast of North America is very helpful for in-class discussion.
Background:
Scientists attach numbered tags to fish to track their travels and growth. Anglers who catch tagged fish contact the scientists using information on the tags. The data they provide can be used to determine how far and how fast fish travel and how quickly they grow.
Striped bass, Atlantic sturgeon, and American shad are born in the freshwater part of the Hudson but eventually swim out into the Atlantic Ocean. They spend most of their adult lives at sea, returning to the river only to spawn (lay eggs). We think of them as "our" fish, but their visit here is just one piece of their long-distance migrations. Fishes with this life cycle (living in the ocean but entering fresh water to spawn) are called anadromous fishes.
Distances on the Hudson are often measured in Hudson River Miles. Hudson River Miles start at the southern tip of Manhattan. This spot, called The Battery, is River Mile 0. The estuary part of the Hudson ends at the Federal Dam in Troy at River Mile 153.
Activity:
- Discuss the concept of migration and the anadromous life cycle of many Hudson River fish.
- Introduce the Hudson River Miles system.
- Go over the worksheet with the class or hand out as an in-class or homework assignment.
- Note that some questions require students to add distance traveled between a point upriver and New York to distance traveled from New York to another site along the Atlantic coast. A map of the U.S. east coast is very helpful here.
Assessment:
- Have students share answers to questions from worksheets, or collect and grade sheets.
- Make up similar elapsed time/distance/growth problems for quiz.
Answers:
1. 5 years, 10 inches
2. 69 miles, 11 days
3. 940 miles, 4 months
4. 297 miles, 27 days
5. 530 milesResources:
The Hudson River Foundation's striped bass tagging program posts results at http://www.hudsonriver.org/sb/ Illustrations and information about the fish described in this activity can be found in the Division of Fish, Wildlife, and Marine Resources section of the New York State Department of Environmental Conservation website at http://www.dec.ny.gov/animals/269.html


