Researchers are compiling information on the status of Africa's natural resources using satellite data.

Liquid Mercury

Mercury contamination in rivers can spread to nearby birds, even ones that don't eat fish or other food from the water, according to a new study. Researchers found high levels of mercury in the blood of land-feeding songbirds living near the South River, a tributary of the Shenandoah. The source of the mercury was spiders, the study found.