Seaside sparrow (Ammodramus maritimus) chicks chirp and beg their parents for food from a well-hidden nest in a Gulf of Mexico marsh. Researchers from the Gulf of Mexico Research Initiative have been spending a lot of time trekking through the marsh looking for these nests since the Deepwater Horizon oil spill in 2010. Why? They want to figure out whether oil spills in the ocean affects birds and other vertebrates on land. In 2013, about half of the sparrow parents who laid their nests in unoiled marshes successfully reared their nestlings to fledging, when they leave the nest—but only 5 percent of those laid in oiled marshes did the same. Read the rest of the story.