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Why is Nebraska
such a special place for migrating birds?

Migratory pathways evolved over the eons. Birds chose these pathways expecting a moderately stable environment. They chose to go to spots with sufficient food and cover along appropriate routes that connected survivable winter ranges with suitable breeding areas.

Still, the environment has never stopped changing. Fortunately, except for catastrophic events that have punctuated the history of life from time to time, change occurred at a gradual rate. This rate of change was slow enough that the processes of evolution allowed bird populations to make modifications in themselves and their habits that made up for the changes in the environment and ensured their continued existence.

But human impacts on the environment have generated faster rates of change. Changes can happen faster than many species can adapt to them. For example:

• A wetland long used by shorebirds as a critical foraging site on their extended journey from South America to the arctic tundra could be drained and cultivated during the short interval between the birds' spring and fall passages.
• Warblers might return from the tropics to find clear-cut mountainsides with no other suitable habitat open for their use.
• Wintering sparrows might come down from the north and find that the weedy fields that used to be in the floodplains of major rivers and once offered cover and food have turned into orderly rows of stubble or the asphalt and lawns of industrial parks.

We know birds can't use these altered habitats, but we don't know the consequences of these events on migrant populations. Before we try to do anything to soften the impacts of these changes, we must first know the consequences of these changes.

In his book, Where Have All the Birds Gone? John Terborgh states "Migration is a chain whose strength is that of its weakest link." Since birds spend as much as half of the year or more en route between breeding grounds and wintering areas, the habitats they depend on during this period are critical links to their survival. When stopover habitat is lost or degraded, more birds might die while migrating. This loss of habitat can also have serious repercussions for nesting success.

For example, birds heading north are already faced with limits – they have a relatively short amount of time available to get to the breeding grounds, establish a territory, pair with a mate, and get on with the further demands of raising young. If a bird arrives at the breeding grounds late or in poor condition because of inadequate food and rest en route, this is likely to jeopardize the bird's ability to reproduce.

Inland stopover areas will continue to be affected by land use policies, especially policies involving development, ranching, agriculture, forestry, water use, and oil and wind exploration.

For the grand phenomenon of bird migration to continue, it will be necessary to find a balance between economic needs and the needs of migrants.

Economic growth based on bird watching and ecotourism is proving to be a successful alternative in a number of key stopover areas across the globe, including Nebraska. Each spring, a million and a half to three million ducks pass through Nebraska. They have the potential to bring human visitors with them, as long as there are places for the birds to stop, feed, and rest.