Environment and nature

This photo provided by Laura Cooper from the Nelson County Farm Bureau shows a yak in Lovingston, Va,, on Wednesday, Sept. 11, 2019. Authorities say the yak on its way to the butcher's shop escaped to the nearby mountains avoiding animal control officers and treats trying to lure it back into a trailer. The yak named Meteor was on its last ride Tuesday from Buckingham, Virginia, to the butcher when it got out of its trailer. (Laura Cooper/Nelson County Farm Bureau via AP)

Environmental Protection Agency Administrator Andrew Wheeler, right, signs a document in front of Assistant Secretary of the Army for Civil Works R.D. James to revoke the Waters of the United States rule, an Obama-era regulation that provided federal protection to many U.S. wetlands and streams, Thursday, Sept. 12, 2019, in Washington. (AP Photo/Patrick Semansky)

Beaufort Police Officer Curtis Resor, left, and Sgt. Micheal Stepehens check a sailboat for occupants in Beaufort, N.C. after Hurricane Dorian passed the North Carolina coast on Friday, Sept. 6, 2019. Dorian howled over North Carolina's Outer Banks on Friday — a much weaker but still dangerous version of the storm that wreaked havoc in the Bahamas — flooding homes in the low-lying ribbon of islands and throwing a scare into year-round residents who tried to tough it out. (AP Photo/Tom Copeland)

This undated photo provided by the U.S. National Park Service shows a dead seal found on a beach near Kotzebue, Alaska. Federal marine mammal biologists have declared an "unusual mortality event" over the deaths of ice seals off Alaska's northwest coast. The cause of the deaths is not known. The fisheries arm of the National Oceanic and Atmospheric Administration says the declaration covers ringed, bearded and spotted seals. (Raime Fronstin/National Park Service via AP)

FILE - In this May 9, 2008 file photo, male sage grouses fight for the attention of females southwest of Rawlins, Wyo. Montana, Wyoming and other Western states are reporting population declines for the birds in 2019.AP Photo/Rawlins Daily Times, Jerret Raffety, File)/The Rawlins Daily Times via AP, File)

In this June 26, 2019 photo Frontier Airlines jetliners sit at gates on the A concourse at Denver International Airport in Denver. A new report says U.S. airlines are increasing their emissions of climate-changing gases much faster than they are boosting fuel efficiency. The International Council on Clean Transportation said Thursday, Sept. 12, 2019 that carbon dioxide emissions and fuel burning rose 7% from 2016 to 2018, overshadowing a 3% gain in fuel efficiency. The report ranked Frontier the most efficient among the 11 largest U.S. airlines. The Denver-based carrier has added more than 40 Airbus jets with more efficient engines. (AP Photo/David Zalubowski)

FILE - In this June 7, 2018, file photo, a puddle blocks a path that leads into the Panther Island Mitigation Bank near Naples, Fla. The Trump administration on Thursday, Sept. 12, 2019, revoked an Obama-era regulation that shielded many U.S. wetlands and streams from pollution but was opposed by developers and farmers who said it hurt economic development and infringed on property rights. (AP Photo/Brynn Anderson)

FILE - In this undated file photo provided by the U.S. Fish and Wildlife Service, caribou from the Porcupine Caribou Herd migrate onto the coastal plain of the Arctic National Wildlife Refuge in northeast Alaska. (U.S. Fish and Wildlife Service via AP, File)

In this Thursday Aug. 15, 2019 photo, dairy farmer Fred Stone pauses while working in the milking room at his farm in Arundel, Maine. Fred Stone and his wife Laura, whose dairy farm is contaminated by toxic chemicals known collectively as PFAS, so-called "forever chemicals," have high PFAS levels in their blood. (AP Photo/Robert F. Bukaty)

German Chancellor Angela Merkel is reflected in a door of a Mercedes during her visit to the IAA Auto Show in Frankfurt, Germany, Thursday, Sept. 12, 2019. (AP Photo/Michael Probst)