Sanderling Plan - Western Hemisphere Shorebird Reserve Network

Tabilo et al. 1996, MacWhirter et al. 2002), as well as in the Guianas (Morrison and Ross 1989).
Sublethal effects of these agricultural and urban pollutants (including organochlorines,
organophosphorus insecticides, heavy metals, and plastics), have not been studied. Contaminants
may be a serious threat to Sanderlings wherever concentrations are high or persistent.
Industrial and agricultural contaminants in food sources may be especially dangerous to
shorebirds. As the fat from these food sources is burned during migratory flights, the
contaminants are released in high doses. This potentially reduces a bird’s ability to refuel or to
escape predators at a subsequent stopover site. (Butler et al. 2004).
Disease
Diseases may play an important role in influencing population trends of the Sanderling.
Increasingly, water quality and quantity have become an issue at shallow lakes in the Canadian
Prairies region and the United States (Great Lakes). The frequency and intensity of toxic
outbreaks (e.g., avian botulism) has increased in recent years, presumably due to warmer water
temperatures (global climate change) and shallower waters (water manipulation for agriculture,
or extended drought-like conditions concurrent with global warming).
Avian botulism outbreaks cause widespread die-offs of waterbirds, claiming tens of
thousands of shorebirds (Strauman 1996), among many other species. Although historical
records of avian botulism outbreaks are very common, specific information on shorebird die-offs
from these events is limited because shorebirds are rarely identified to species.
Some of the shallow lakes that serve as major staging areas for the Sanderling in spring
have experienced increased rates of botulism (Adams et al. 2003) and associated waterbird
mortalities. However, at present, most botulism outbreaks occur during the fall migration period
(and at select wetlands), at a time of year when Sanderlings are more dispersed.
CLIMATE CHANGE
It is important to include a section on climate change in this plan despite uncertainties
around potential climate change impacts. The reasons are twofold: 1) climate change is here;
current levels of carbon dioxide in the atmosphere will continue to influence the climate (and
landscape) for decades, even as new policies are put into place to reduce new inputs; and 2) in
many cases, climate change will not manifest itself as a new and independent management
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