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<br />at Aransas and were believed shot during fall migration (2), avian predation (1), and arriving
<br />at the refuge with a trauma injury following fall migration (1) (Lewis et al. 1992).
<br />Between 1947 and 1990, 51 whooping cranes have been lost on the wintering grounds.
<br />This represents 1.8 percent of 2,823 wintering cranes. Three losses occurred among
<br />cranes summering on Aransas NWR. During these same years, birds that started migration
<br />in the spring and failed to return in the fall (i.e., April to November mortality) numbered 158.
<br />Twenty four percent of the total flock mortality occurred on the wintering grounds.
<br />Mortality during April through November is 3.1 times greater than mortality on the wintering
<br />grounds. Spring migration, summer, and fall migration are the periods which should receive
<br />emphasis to further diminish mortality of fledged birds (Lewis et al. 1992). As previously
<br />noted, the principal known cause of loss during migration is collision with utility lines.
<br />However, management actions need to be taken wherever they can effectively reduce
<br />mortality, regardless of relative rates of losses.
<br />F. Economic Importance
<br />There is much evidence that people value whooping cranes. Numerous books, magazine
<br />articles, television programs, and nature documentary films have been produced about this
<br />magnificent bird. Corporations have funded whooping crane research and recovery efforts
<br />and also have used whooping cranes in promoting their environmental concern. The
<br />Whooping Crane Conservation Association, a nonprofit group, was formed in 1961 to
<br />promote conservation of whooping cranes and to educate the public. Other organizations
<br />such as the National Audubon Society, have participated in whooping crane research,
<br />conservation, and education. The Platte River Whooping Crane Habitat Maintenance Trust
<br />was established in 1978 as a nonprofit conservation organization to protect and enhance
<br />habitat for migratory birds in Nebraska along the Platte and North Platte rivers, especially to
<br />protect and maintain whooping crane habitat.
<br />Values for whooping cranes are also expressed in monetary expenditures. Each year
<br />70,000 to 80,000 people visit Aransas NWR, most during the winter, spending significant
<br />amounts locally on lodging, gasoline, and supplies (Ellen Michaels, pers. comm.). In 1970,
<br />one tour boat, The Whooping Crane, offered weekend day -trips from Rockport, Texas, to
<br />view the cranes along the GIWW. By 1990, five boats offered this opportunity, spanning
<br />every day of the week. During 1990 -91, approximately 17,000 people took these tours,
<br />paying an average of $20 per ticket, for a total seasonal expenditures of $340,000 (Ellen
<br />Michaels, pers. Comm.). The city of Rockport estimates that wildlife - related activities result
<br />in annual gross economic benefits of $6 million to the local economy (Rockport Chamber of
<br />Commerce). Some of these benefits result from the nearby presence of whooping cranes.
<br />Large numbers of sandhill cranes along migration routes and winter areas have begun to
<br />attract tourist dollars to other areas in North America. In several of these areas, one of the
<br />additional attractions for tourists is the possibility of sighting whooping cranes.
<br />Approximately 80,000 people visit the Platte River area of Nebraska each year during the
<br />peak of spring crane migrations, expending approximately $15 million (Lingle 1992). This
<br />interest has prompted the Grand Island, Nebraska, Chamber of Commerce to sponsor an
<br />annual festival, "Wings over the Platte ", to further promote the avian attractions.
<br />Approximately 75,000 people annually visit Bosque del Apache NWR, New Mexico, the
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