Northern Prairie Wildlife Research Center
Status Survey and Conservation Action Plan
Threats: Other Environmental Factors
Abiotic factors play an important role in both the short-term and long-term fate
of cranes, especially in cases involving the effect of stochastic events on small
or concentrated populations. Storms and other weather events can have important,
and sometimes catastrophic, effects on crane populations (Merrill 1961, Tacha
and Vohs 1984, Johnson and Barnes 1991). Drought not only dries up wetland breeding
areas, but can lower production of young birds by reducing food supplies and increasing
the vulnerability of nests and chicks to predation (Neumann 1991, Kuyt et al.
1992). Drought may also increase the pressure to expand agricultural production
into wetland areas. Fires can pose a significant threat when young cranes are
present (Allan 1990, Windingstad 1988, Johnson and Barnes 1991, S. Smirenski pers.
comm.). Finally, the climatic changes predicted under most global warming scenarios
would have profound impacts on existing crane habitats.
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