Segments in this Video

Introduction to the Great Lakes (03:15)


The inland seas hold one fifth of the planet's fresh water, providing energy and drinking water to millions—and their interconnected aquatic ecosystem is subject to environmental threats. (Credits)

An Aquatic Ecosystem (02:18)

A school group takes a boat ride into Lake Michigan to learn about life beneath the water’s surface.

Geologic Features (02:15)

The Great Lakes were formed by glaciers receding after the Ice Age 20,000 years ago. Together they hold nearly 20% of the world's fresh water supply. We learn about the region's geography.

Regional Inhabitants (01:23)

Native tribes settled the Great Lakes for centuries. European explorers came in the 1600s followed by immigrants from Scandinavia and Germany in the 19th century. Logging and coal mining industries developed from abundant natural resources.

20th Century Transportation Routes (02:28)

The Great Lakes began to be used for shipping goods between America's heartland and the Atlantic, uniting a vast region and contributing to industrialization and urban development.

Wild Rice Harvest (02:33)

A wetland on the Bad River Indian Reservation in a Lake Superior has remained pristine for 2,000 years. Chippewa tribe members gather the indigenous grass central to their culture and survival.

Inter-Generational Traditions (04:02)

We learn about the fresh water wild rice ecosystem in Lake Superior. A Chippewa game warden teaches his granddaughter how to harvest.

Ice Experts (07:31)

Arctic winds bring early winter to Wisconsin. Residents of Madeline Island in Lake Superior rely on wind sleds—a local invention—to connect them with civilization until the ice is thick enough to drive across.

Mystery of the Edmund Fitzgerald (06:14)

In the spring, shipping lines begin again on the Great Lakes. 10,000 ships have sunk in the treacherous waters since records began. We learn about the investigation of an ore vessel that disappeared during a storm in 1975.

Environmental Stress (04:18)

During the 1960s the Great Lakes showed signs of industrial damage. The U.S. and Canada signed a joint agreement protecting the watershed—initiating a large scale cleanup effort. The walleye's return to Lake Erie is a measure of success.

An Ecological Balancing Act (04:46)

In 1959, the St. Lawrence Seaway opened the Great Lakes to ocean shipping—bringing invasive species such as the parasitic sea lamprey. Wildlife officials treat its spawning grounds with a chemical to control the population and restock native fish.

Invasive Threat (03:09)

We learn about a zooplankton from the Baltic region introduced to the Great lakes by international shipping vessels. Biologists predict it will compete with native fish for food, upsetting the food web.

Zebra Mussels (03:39)

Ship ballast water has brought the unwelcome Caspian Sea mollusk to the Great Lakes—threatening both infrastructure and the food web. Researchers try to stay ahead of invasive species in the closed ecosystem.

Chemical Contamination (04:47)

Biologists study the affect of industrial pollution on migratory species in the Great Lakes. The concentration increases as it moves up through the food chain—deformities in birds indicate system disruption.

International Commission on the Great Lakes (01:25)

Citizens, public and private groups from the U.S. and Canada gather to voice their concerns about environmental threats to the region and to meet future challenges.

A Delicate Ecosystem (01:47)

The Great Lakes have been a symbol of unlimited potential in the New World. However, recent environmental threats prove they must be protected for future generations.

Credits: Great Lakes, Fragile Seas (01:40)

Credits: Great Lakes, Fragile Seas

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Great Lakes, Fragile Seas

DVD (Chaptered) Price: $169.95
DVD + 3-Year Streaming Price: $254.93
3-Year Streaming Price: $169.95



The Great Lakes basin is a melting pot of tradition and history. The same waters that nourish the region’s wildlife have also shaped the customs of the people who live along its shores. Join us for a survey of the Great Lakes and the fascinating people and wildlife that surround them. We'll engage with cleanup efforts to keep the lakes healthy and vital; take up an investigation into the sinking of the ship the Edmund Fitzgerald; and encounter a diverse group of citizens who gather to voice one common conviction—the survival of their culture depends on the preservation of the lakes. A National Geographic Production. (58 minutes)

Length: 58 minutes

Item#: BVL50177

Copyright date: ©1991

Closed Captioned

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Not available to Home Video, Dealer and Publisher customers.

Only available in USA.