Once a species disappears, there is no way to bring it back. Breeding programs can help, but many species do not respond very well to such efforts; it is far better to prevent a species from becoming endangered in the first place.
Many species provide, or have the potential to provide, value to human beings. In addition, people are constantly finding new uses for plants and animals, including as sources of food and medicine. Rates, [PDF]. Many agricultural and industrial products such as iron ore, coal, limestone, metals, petroleum, coke, and chemicals are derived from the Lake Michigan basin's resources.
The water of Lake Michigan serves many purposes. It supports large commercial and sport fishing industries. It provides industrial process and cooling water, and water for agricultural irrigation.
Fleets of freighters pass over the lake carrying bulk commerce items. Lake Michigan serves as a source of drinking water, as a place for swimming and fishing, as a scenic wonderland, and as a drainage basin for municipal and industrial waste and runoff from the surrounding lands. Lake Michigan provides extensive recreational opportunities, fueling a thriving tourism industry in the Great Lakes states.
Open-water prey fish such as alewife and bloater have declined dramatically since the s. Large rivers and associated inland lakes formed by drowned river mouths provide important habitat connections and nutrient inputs. In shallow, rocky areas of the lake, excess nutrients can fuel the growth of bottom-dwelling algae that washes ashore and fouls beaches.
The rotting algal muck can also harbor bacteria implicated in die-offs of fish and waterfowl in northern Lake Michigan. Dam removal and management efforts have improved conditions for spawning fish in many rivers. Many rivers in the northeastern part of the basin support naturally-reproducing runs of introduced salmon.
Though fish species appear in the Lake Michigan watershed, only 68 are found in the lake itself. Five deepwater cisco species disappeared from the lake due to overfishing and invasive species. Native strains of lake trout were also extirpated by the mids.
Karamanski, and Philip Elmes. Wille, Lois. All Rights Reserved. Portions are copyrighted by other institutions and individuals. Additional information on copyright and permissions. Lake Michigan Next.
Lake Michigan.
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