Across Washington State, hydroelectric dams are blocking salmon as they migrate to their spawning grounds. Enter the salmon cannon. Ingrid Taylar/Flickr hide caption

itoggle caption Ingrid Taylar/Flickr

Florida Gov. Rick Scott helps release a 30-pound green sea turtle in the Gulf of Mexico in Marathon, Fla., in 2012. The governor is making environmental protection part of his re-election campaign. Andy Newman/AP/Florida Keys News Bureau hide caption

itoggle caption Andy Newman/AP/Florida Keys News Bureau

Patrick Roy's company, Coastal Rental Equipment, used to rent these large pumps to offshore divers who work for oil and natural gas drillers. After the BP oil spill, when the government introduced a moratorium on drilling in the Gulf of Mexico, the Patterson, La., business suffered losses and eventually shut down. Jeff Brady/NPR hide caption

itoggle caption Jeff Brady/NPR

New Yorkers can take city-run classes to learn how to make their homes and businesses less attractive to these guys. Ludovic Bertron/Flickr hide caption

itoggle caption Ludovic Bertron/Flickr

Big brown bats like this one are relatively common in urban areas, sometimes roosting in buildings. Contrary to popular belief, bats rarely carry rabies and are not rodents. They belong to the order Chiroptera, which means "hand-wing." Courtesy of Robert Marquis hide caption

itoggle caption Courtesy of Robert Marquis

The granulated surface of the lake bed known as the Racetrack is a favorite destination for tourists — and for scientists who want to investigate trails left by the meandering stones. Momatiuk - Eastcott/Corbis hide caption

itoggle caption Momatiuk - Eastcott/Corbis

A view of a road closure to the Vattnajokull glacier, the site of the Bardarbunga volcano under the Dyngjujokull ice cap in Iceland, on Sunday. Scientists had worried that the volcano might spew steam and ash, but say now that it appears to have quieted. Vilhelm Gunnarsson/ Fretabladid/EPA/Landov hide caption

itoggle caption Vilhelm Gunnarsson/ Fretabladid/EPA/Landov

A young Chinook salmon, called a smolt, near Vallejo, Calif., on April 24, 2014. North Coast tribes and environmentalists fear that the smolts and Chinooks may not survive this year's low river flows and warm water. Rich Pedroncelli/AP hide caption

itoggle caption Rich Pedroncelli/AP

Giant Cabbage Weigh-Off 2013 winners (with placards, left to right): Scott Rob (92.1 pounds), Keevan Dinkel (92.3 pounds) and Brian Shunskis (77.4 pounds). The growers are joined by the cabbage fairies, a group of women who for 15 years have volunteered at the cabbage competition. Clark James Mishler/Courtesy of Alaska State Fair hide caption

itoggle caption Clark James Mishler/Courtesy of Alaska State Fair

Maria Benech of the U.S. Forest Service surveys a severely burned patch of forest. Almost 40 percent of the burned area looks similar. Lauren Sommer/KQED hide caption

itoggle caption Lauren Sommer/KQED

Louis E. Pratt, master ivory cutter for Pratt, Read & Co., shows off eight ivory tusks, April 1, 1955. Courtesy of Deep River Historical Society hide caption

itoggle caption Courtesy of Deep River Historical Society