Papers in the Biological Sciences
Date of this Version
12-9-2008
Abstract
Time proceeds inexorably onward, and it has been 17 years since the first edition of Crane Music was published. During that time more than a billion people have been added to the earth's roles, and global warming has increasingly been recognized as a real tlu:oat to our planet's future. Although during that period a small percentage of Americans have become very rich through advances in technology, expanding markets and globalization, wildlife in general has suffered. Continuing population growth and associated economic and ecological pressures have resulted in greatly increased deforestation, wetland drainage, and destruction of natural habitats. Additionally, global climate changes are bringing on unforeseen massive ecological changes that will have serious effects on crane populations, especially in arctic and alpine regions (Harris, 2008).
Downward population trends in wildlife that are associated with these factors are especially apparent among native grassland and wetland-dependent birds; nearly all of North America's grassland-adapted birds are now in serious continental decline, and probably much the same is true elsewhere in the world. Most of the world's cranes are also to a large degree dependent on grasslands and wetlands; those that are generally the rarest and most in danger of extinction are the ones most strongly dependent on extensive wetlands. The whooping, Siberian, white-naped, wattled and Japanese (red-crowned) cranes are all strongly wetland-dependent for breeding, and are now among the world's rarest and most endangered species. On the other hand, some relatively herbivorous and terrestrial species such as the sandhill, Eurasian, demoiselle and blue cranes have learned to take advantage of agricultural technology by incorporating into their diets of native plants various cultivated grains, such as com and wheat in Europe and rice in Asia. As a result these species have exhibited local, regional or even national population increases. Such foraging practices have often brought cranes into conflict with agricultural interests, resulting in economic conflicts and sometime draconian control measures.
An overview of the current status of the world's cranes is perhaps in order, to bring up to date the accounts given earlier in Crane Music, which was written nearly 20 years ago.
Includes:
Summary of the Cranes of the World and Their Status
The Sandhill Crane
The Whooping Crane
Supplemental References and Bibliographic Notes
Comments
Copyright (c) 2008 Paul A. Johnsgard.