Grade 5 Teacher Background Information

Teacher Background

This unit focuses on oceans and rivers as an interconnected system into which people are interwoven. From the systems perspective, Alaska Seas and Watersheds are dynamic physical and chemical systems that make up the environment, which supports dynamic biological communities. As a major player in biological communities, people have diverse relationships with the environment and with individual species of other living things. People fish for and eat salmon, halibut, and a variety of other marine and anadromous fish; eat ice cream and shampoo their hair with products that have an ingredient derived from seaweed; enjoy watching whales and waterbirds, walk on the beach, build their homes or recreational cabins on the shores of bays, lakes, and rivers; and are inspired to create paintings, songs, and poems about water environments. Their actions, particularly consumption and waste disposal, have the potential to disrupt ecological relationships and the integrity of marine and aquatic ecosystems and to provide stewardship of the systems within which they are such an integral member.

The roles and relationships of people in these systems have changed significantly over the thousands of years that they have inhabited the land that is now Alaska. The ocean and rivers have been the means by which people first inhabited Alaska, by crossing the land bridge and arriving by skin boats from the Asian continent, and later “discovering” it from Europe. Boats and ships remained the primary mode of travel to Alaska until well into the twentieth century when roads and airplanes improved the connections.

Many of the animal species that depended on marine and freshwater environments were in turn the means by which the earliest human inhabitants met needs for food, clothing, and skin boats. From the beginning, the importance of these animals was recognized in cultural expressions of song, dance, and ornamentation of tools and clothing. The use of marine and freshwater animals expanded to an industrial scale after colonization by Russians, British, and Americans who sought whales, furs, and fish for export. Harvests and populations grew, at the expense of the original Native Alaskans and the targeted fish and wildlife populations.

As boat technology evolved from the earliest skin boats and log canoes to the modern power skiffs and ocean-going vessels, and use expanded from local to being exported to Europe and Asia, the technology for harvesting animals from seas and rivers also evolved from hand-held lines and fishwheels to traps, pots, large nets, longlines, and trawls. The nomadic lifestyle of Alaska Natives, which was well suited to the patchy and seasonal abundance in the Far North, evolved into permanent settlements, often because there was a nearby resource to extract or to process for export. Both the scale and efficiency of harvests increased, causing decimation of several marine mammals, until conservation measures were finally put into place. In addition, as the population of Alaska grew, so did the uses of ocean and river environments and animals—through recreation (boating, kayaking, beachwalking, beachcombing, wildlife-viewing), economic development (fishing, offshore oil development, marine transportation, tourism), and inspiration for enjoying beauty or creating art. The impact of people on the physical and chemical aspects of the environment increased through alterations of shorelines for residential and industrial uses; large-scale use of land for timber harvest, agriculture, and oil development; and water and air pollution.

Today, sustaining the productivity of Alaska Seas and Watersheds is crucial to Alaskans and people throughout the world.

From the beginning, careful observation of the Alaska environment has been key to predicting what might happen in the future and adapting human activities accordingly. The early Native people who failed to learn did not survive. A rich resource of traditional ecological knowledge has been passed down in Alaska Native cultures through stories, oral histories, and the practice of honoring the experience and wisdom of elders. Many Alaskans have lived their entire lifetime in areas of Alaska that they have come to know well and observe closely over many years. They are a rich source of local ecological knowledge.

Since the 1900s, after the overexploitation that occurred at the time of colonization of Alaska, science has been employed to develop conservation measures for Alaska’s fish and wildlife populations. Alaska scientists have an important role to play in seeking to understand the ecology of seas and river systems. The application of scientific knowledge of Alaska marine and freshwater ecosystems provides a rational means for balancing harvests and other human activities with their effects on ecosystem, so that harvests and other uses are sustainable. Due to the integral role of people in the system under study, the physical, chemical, and biological sciences are often not sufficient to answer the questions being posed. The social sciences, which focus on the study of human actions, attitudes, and motivation, are increasingly important to understanding and to fashioning solutions to environmental problems related to the impact of growing human populations and pressures on marine and aquatic ecosystems.

Formative Assessment Probe

Background information on formative assessment probe and 5th grade probe.

Purpose

The purpose of this probe is to elicit students’ ideas about human impact on the environment.

Explanation

The best answer is Nancy’s, “The trash and pollutants people put into the environment everywhere can affect the ocean, life in the ocean and on land.”
Bob’s idea is not the best choice. Since all watersheds eventually lead to the ocean, what happens on land and/or freshwater can have an impact on the ocean.
Chris’s idea is not the best choice. Plastic can end up in a body of water and have an impact on animals.
John’s idea is not the best choice. The ocean is indeed very large, and covers most of the earth, but not all garbage disappears in the ocean. Plastics in the ocean as well as other marine debris are a huge problem for the living things in the ocean.

Administering the Probe

Ask students to carefully read the probe, decide which student they most agree with, and explain their thinking.

Grade Level Curricular and Instructional Considerations

In her book, Making Sense of Secondary Science, Rosalind Driver refers to a study conducted by Michael J. Brody regarding student understanding of science and natural resource concepts related to current ecological crises. The Brody study “indicates few changes in knowledge about ecological crises between the ages of 9 and 16. However, this study identified changes in children’s ideas of pollution. Nine-year olds regarded pollution as something which is directly sensed by people and which affects people or other animals. They did not consider that harm to plants constitutes an environmental problem. They thought that air can somehow circulate pollution. Pupils aged 13 had a more conceptual understanding of ecological crises, including a concept of cumulative ecological effects.” The following misconceptions were held by at least half of the students included in the study:

• Anything natural is not pollution;
• Biodegradable materials are not pollutants;
• The oceans are a limitless resource;
• Solid waste in dumps is safe;
• The human race is indestructible as a species.

“By grades 3 and 4, students regard pollution as something sensed by people and know that it might have bad effects on people and animals. Children at this age usually do not consider harm to plants as part of environmental problems; however, recent media attention might have increased students awareness of the importance of trees in the environment. In most cases, students recognize pollution as an environmental issue,…”(National Science Education Standards, p.139)

“Due to their developmental levels and expanded understanding, students in grades 5-8 can undertake sophisticated study of personal and societal challenges. Challenges emerge from the knowledge that the products, processes, technologies and inventions of a society can result in pollution and environmental degradation and can involve some level of risk to human health or to the survival of other species.”

“By grades 5-8, students begin to develop a more conceptual understanding of ecological crises. For example, they begin to realize the cumulative ecological effects of pollution. By this age, students can study environmental issues of a large and abstract nature, for example, acid rain or global ozone depletion. However, teachers should challenge several important misconceptions, such as anything natural is not a pollutant, oceans are limitless resources, and humans are indestructible as a species.” (National Science Education Standards, p.167)

Related National Science Education Standards

K-4 Changes in Environment

• Environments are the space, conditions, and factors that affect an individual’s and a population’s ability to survive and their quality of life.

• Changes in environments can be natural or influenced by humans. Some changes are good, some are bad, and some are neither good nor bad. Pollution is a change in the environment that can influence the health, survival, or activities of organisms, including humans.

Related National Science Education Standards

5-8 Natural Hazards

• Human activities also can induce hazards through resource acquisition, urban growth, land-use decisions, and waste disposal. Such activities can accelerate many natural changes.

Related Benchmarks for Science Literacy

3-5 Interdependence of Life

• Changes in an organism’s habitat are sometimes beneficial to it and sometimes harmful.

The Bidarki and Halibut Cove Stories

The unit includes two stories that provide an opportunity to develop a perspective on the use of the scientific process and other ways to reach a conclusion about cause and effect relationships.

The bidarki story describes a deliberate combination of scientific process with traditional ecological knowledge to determine why a chiton species used traditionally as a subsistence food by Native people in the villages of Port Graham and Nanwalek had declined in numbers and size.

The Halibut Cove story is one of local ecological knowledge about a series of events occurring at a time when herring stocks declined precipitously and eventually disappeared from Halibut Cove. No scientific data were collected that would confirm or disprove the conclusion.

The two stories together can serve as a springboard for discussion about the types of questions and investigations that scientists would pursue to verify local or traditional cause-and-effect stories using the scientific process. Caution is required, however, because beliefs arising out of experience or respect for traditional ways of transmitting knowledge are often deeply held and have cultural significance. The discussion should focus on the standards of evidence and the scientific process that is required to reach a scientific conclusion, in contrast to a plausible or logical explanation of observations. Everyone’s life experiences and observations are valid, but specific conclusions may not be verifiable through the scientific process.

Fishing for the Future

The Halibut Cove Story

Halibut Cove, Alaska, is located on the south side of Kachemak Bay on the east side of Cook Inlet. It was occupied by Alaska Native people in prehistoric times for thousands of years, based on the remains found in their midden (or garbage) piles excavated by archaeologists.

In the early 1900s, a large-scale herring fishery developed to catch and process herring that came to spawn in Halibut Cove in the spring and came back in the fall to overwinter in the bay. Steller sea lions, seals, porpoises, belugas, and many species of birds ate large quantities of the fish and sticky eggs that female herring deposited on the eelgrass beds in the intertidal areas. Pods of beluga whales and harbor seals fed on the herring in Halibut Cove Lagoon.

The herring were called “bloaters” due to their large size. They were 12-14 inches in length. Hundreds of people began arriving to harvest the herring in Kachemak Bay during the fall, winter, and spring fishing seasons. At the peak of the fishery, up to 3,000 people worked in the fishery and 38 “saltries” operated in Halibut Cove to pack the herring in brine (saltwater) and barrels for shipment to the East Coast. The town had ocean docks for steamships and a pool hall.

The fishery began in 1911 and ended in 1928, when the saltries stopped operating due to lack of fish. The herring never again returned to Halibut Cove or to other bays and coves in Kachemak Bay in large numbers in the fall.

The end of the herring has never been explained, but possible causes include overfishing and pollution of the spawning areas. In the mid 1920s, large purse seines were allowed to catch the herring in addition to the gillnets that had been used. Complaints were made to the territorial fish commissioner that small herring caught in the purse seines were being “dumped,” which meant that large numbers of both small and large fish were killed before they could reproduce the following spring. The saltries all dumped their fish waste on the beach or in the shallow waters offshore on top of the eelgrass beds where the herring spawned. Large quantities of fish waste could have smothered the eelgrass beds and blocked the light.

Halibut Cove became a ghost town with a few remaining men. It later developed into a small town with art galleries and a restaurant visited by tourists and cabin owners during the summer, with 30-50 year-round residents.

(Adapted from The Story of Halibut Cove by Diana Tillion and the Kachemak Bay Ecological Characterization by the Kachemak Bay Research Reserve)

Fishery Facts

The world’s fisheries are under more pressure than ever before. From 1950 to 1990, there was a fivefold increase in the world annual fish catch. The average yearly per person fish consumption in the industrialized world (59 pounds) is three times that of people in the developing world (20 pounds). Fish demand remains high: An additional 15.5 million tons of fish will be required by 2010 just to maintain current rates of fish consumption. Today, 70 percent of the planet’s marine stocks are fully exploited or overexploited. The number of people fishing and practicing aquaculture worldwide has doubled since 1970. More than 21 million people are full-time fishers, and 200 million depend on fishing for their livelihood. Asia contains the vast majority of the world’s fishers. In the early 1950s, developed countries took 80 percent of the world’s fish catch. Today, they take only 36 percent of the catch, while developing countries take 64 percent. The technology used to catch fish and the number of fish caught per fisher varies enormously. Modern fleets are the most environmentally destructive, as they use enhancements such as airplanes, radios, seafloor maps, and video sonar to track down fish schools. Once they have found the fish, these fleets use large nets to drag up not only the targeted fish but also coral, the seafloor, and around 27 million tons annually of “by-catch”—non-marketable fish that are killed and thrown overboard. To compensate for reduced wild fish stocks, more and more fish are being farmed. Nearly a third of all fish for food is harvested from aquaculture. For every 11 pounds of beef grown globally, there are now 4.5 pounds of farm-raised fish produced. Fish farming causes environmental destruction comparable to the replacement of rain forest with cattle ranches. About 11 pounds of wild ocean fish need to be caught to feed each pound of farmed species. Thailand, which has one of the biggest aquaculture industries, has lost half its mangrove forests due to shrimp farming. Densely stocked salmon farms in British Colombia, Canada, produce waste (including fertilizer, effluent, and fishmeal) equivalent to that generated by half a million people. Despite these numbers, there is still hope for the world’s fisheries. Fisheries can be restored through the adoption of sustainable fishing practices. With the proper incentives, fishers can be encouraged and rewarded in their effort to sustainably manage marine resources. For example, partnerships between local communities and scientists in the central islands of the Philippines resulted in the establishment of marine reserves to help manage overexploited fisheries. The establishment of no-fishing zones in the reserves has increased catches in adjacent fishing grounds. Another solution is to use the power of the market to encourage sustainable fishing practices. The Marine Stewardship Council together with the World Wildlife Federation and Unilever, one of the largest makers of fish products, has developed a certification process that includes a label telling consumers that fish products came from fisheries certified as sustainable.

References: The New Internationalist magazine issue 325, www.newint.org; The United Nations Food and Agriculture Organization, www.fao.org; Environmental News Service, February 2002, www.enn.com

Ocean Impacts

Use the resources section of this website for local specific information