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All of the hardware that social organizations have put in place in the Platte basin has
<br />produced the wealth that rides with extensive irrigated agriculture, hydroelectric power, urban
<br />and industrial development, wetlands and wildlife for species benefitting from dense riparian
<br />vegetation, increased late summer, fall, and winter season base flows, recreational boating and
<br />other water sports that are served by reservoirs, and outstanding cold water fishing below dams.
<br />On the cost side of the ledger, however, the Platte in many places has become a stream of
<br />narrowed channels intersected by densely vegetated islands and flood plains, destruction of
<br />oxbows and meanders and associated natural wetlands, fish migrations blocked by dams, growth
<br />of woody vegetation no longer swept away at the seedling stage by naturally occurring flood
<br />pulses, and highly variable temperature fluctuations as cold lake bottom waters are periodically
<br />released. In general, the traditional flow regime has been changed to one characterized by lower
<br />and less frequent spring flood pulses, clearer water flows as sediment was trapped behind dams,
<br />more incised straighter channels, and higher mid-to-late summer, fall, and winter flows.
<br />Habitat Requirements of Whooping Cranes, Piping Plovers, and Least Terns
<br />"We are not trying to turn the river back to its pre-European historical condition.
<br />That is impossible. We are trying to maintain pockets of serviceable habitat."
<br />United States Fish and Wildlife Service
<br />What a bird requires of its environment is in limited supply--food, shelter, and nesting
<br />sites. Birds of the same and similar species make similar demands on the habitat-the more
<br />individuals in a given territory, the less supply for any given request. Therefore, many birds are
<br />territorial and compete amongst each other for scarce resources. What, therefore, is needed for
<br />preservation and protection of the several species are larger quantities of habitat to support the
<br />numbers of species competing for the resources available. As human impact has destroyed the
<br />wide shallow braided Platte in most reaches, the story of the whooping cranes, their cousins the
<br />sandhill cranes, least terns and piping plovers is one of being crowded into ever smaller reaches
<br />of viable habitat along with millions of other migrating birds who press into the same area.
<br />Whooping cranes, Grus americana, are among the largest birds in the world-standing
<br />over five feet tall, with a wingspan of 7.5 feet, they weigh on average 14 pounds and frequently
<br />fly 200 to 500 miles per day during migration. They lay two eggs a year in the far north, and live
<br />as long as 40 years. Brilliant white birds, with black wingtips and bare red head tops, whooping
<br />cranes share the central Platte river habitat of the sandhill crane, a smaller, gray, more numerous
<br />cousin. Whooping cranes, one of the most celebrated of endangered species, is a loner--much
<br />less gregarious than its prolific relative, the sandhill. Whooping cranes have a convoluted
<br />windpipe as much as five feet long, that can produce loud and resonant calls while flying.
<br />Audubon asserted that he could hear whoopers at a distance of three miles (Forbush and May
<br />1955). Flocks of sandhills joined by a few whoopers visit the Platte River in February-April and
<br />October as they move from wintering grounds on the Texas gulf to breeding areas in Northern
<br />Canada and then make their autumn return. The fossil record places sandhill cranes in Nebraska
<br />more than nine million years ago, long before there was a Platte River which, by comparison, is
<br />only about 10,000 years old. Well drawn descriptions of whooping and sandhill cranes are
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