Every year thousands of lesser sandhills congregate along the Platte River in Nebraska on their spring migration northwards. Mainly because of local damage caused by the birds during their fall migration, they have been legally hunted since 1961. Can the population survive such persistent destruction?
One may ask the question “How many cranes are enough?” This is perhaps analogous to the rhetorical question as to how many redwood trees are needed to make a viable forest; for a remnant crane population is not only unimpressive but also seemingly does not survive or reproduce well, judging from population trends in the three other sandhill crane subspecies, which are all rare or endangered.
Unless one has witnessed the incredibly large flocks on their wintering grounds or one of the major staging areas, it is impossible to comprehend the excitement and beauty conveyed by a group of several thousand cranes in the air or on a field. Most of the 200,000 or so cranes that use the Platte Valley each spring are found in the vicinity of 11 major roosting sites. These are generally stretches of the Platte or North Platte rivers that are relatively isolated from roads or bridges, and which have an abundance of shallow sandy bars or low islands to which the birds return each evening. Some of these roosts may support nearly 30,000 birds each night, and the dusk and dawn flights to and from the roosts provide one of the most impressive wildlife spectacles in all of North America.
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