Xanda, son of Cecil the lion, is killed by a hunter on a legal trophy hunt in Zimbabwe, like his father two years ago. The six-year-old African lion was wearing a collar that allowed researchers to monitor his behavior.

Several coastal California communities sue 37 oil and coal companies for damages caused by climate change. Marin County, San Mateo County, and Imperial Beach hope to hold the corporations liable under public nuisance laws for expenses related to rising sea levels.

Thanks to the dedication of a teenage environmentalist, flood-prone South Miami becomes the first city outside of California to mandate solar panels on new homes.

A former climate scientist at the Interior Department pens an op-ed criticizing the Trump administration for choosing “silence over science” after he is involuntarily reassigned to an accounting job. He claims he was retaliated against for speaking out about the dangers of climate change, particularly for indigenous Alaskan communities.

A Navajo Nation Council subcommittee rejects the Grand Canyon Escalade, a proposed billion-dollar entertainment complex on Navajo land. The controversial project would have featured a tram, hotels, and a restaurant at the brink of the Grand Canyon. 

To avoid being eaten, a species of jumping spiders imitates ants, which defend themselves more aggressively against predators. Myrmarachne formicaria raise their front legs to mimic antennae and walk in rambling paths like ants following pheromone trails. 

Lead is detected in sinks and water fountains in 47 school districts in Bergen County, New Jersey, likely leeching from old pipes. 35 districts have readings over 15 parts per billion, necessitating immediate action by the districts under EPA laws. 

The California legislature voted to extend the state’s cap and trade program to 2030. The bill received bipartisan support as the state strives to reduce greenhouse gas emissions to 40 percent below 1990 levels by 2030. 

Fracking wastewater contaminates Pennsylvania waterways with endocrine disruptors and radium—even after it has been treated.

A tiger raised in captivity in Russia and returned to the wild is photographed with a cub, raising hopes that the species is repopulating territory in southeast Russia. 

After a Canadian lobsterman is killed trying to disentangle an endangered right whale from fishing gear, the National Oceanic and Atmospheric Administration bans such efforts, then reinstates them a week later for all species but the right whale. 

Wolves in Wyoming killed a record number of livestock in 2016, and wildlife managers responded by killing a record number of wolves. 113 wolves were killed—more than double the total from 2015. 

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