In 1980, five black robins remained on Earth. One female held two eggs, and the species’ survival depended on them. Don Merton, a New Zealand Wildlife Service officer, took those eggs. He had spent
In 1980, five black robins remained on Earth. One female held two eggs, and the species’ survival depended on them. Don Merton, a New Zealand Wildlife Service officer, took those eggs. He had spent sixteen years trying to save the birds. He could only hope the decision did not seal their fate.New Zealand evolved in isolation for millions of years without ground predators. Many native birds nested…
The Alameda Creek watershed in California is showing signs of recovery, with improved water quality linked to the return of trout and salmon. A concrete barrier that had blocked the creek for seventy
The Alameda Creek watershed in California is showing signs of recovery, with improved water quality linked to the return of trout and salmon. A concrete barrier that had blocked the creek for seventy years was removed in the fall of 2025, and within days, two chinook salmon were observed swimming upstream through waters that had been inaccessible since before the first moon landing.To understand t…
For 70 years, a concrete barrier sealed off Alameda Creek in California from the bay. The water behind it was widely considered lifeless, with no salmon or steelhead returning to spawn. In the fall
For 70 years, a concrete barrier sealed off Alameda Creek in California from the bay. The water behind it was widely considered lifeless, with no salmon or steelhead returning to spawn. In the fall of 2025, work crews finally removed that barrier, and within days, two Chinook salmon were observed swimming upstream through water that had been inaccessible to them since before the first moon landing…
Off the coast of British Columbia, a marine ecosystem that had collapsed into barren underwater landscapes has been gradually restored. The recovery did not come from chemical treatments, machinery,
Off the coast of British Columbia, a marine ecosystem that had collapsed into barren underwater landscapes has been gradually restored. The recovery did not come from chemical treatments, machinery, or government cleanup crews. It came from a predator that had been absent from these waters for over a century: the sea otter.For years, giant kelp forests stretched for miles along the British Columbi…
In 1940, 630 beavers lived in the Kawuneeche Valley in Colorado. By 2023, only six remained. Willow trees had thinned, wetlands had disappeared, and roughly 90 percent of the valley’s surface water
In 1940, 630 beavers lived in the Kawuneeche Valley in Colorado. By 2023, only six remained. Willow trees had thinned, wetlands had disappeared, and roughly 90 percent of the valley’s surface water was gone. The valley sits at the headwaters of the Colorado River, which supplies drinking water to about 40 million Americans along its 1,450-mile path through the western United States. Ecologists had…
Bison were reintroduced to the long-grass prairies thirty years ago, an ecosystem that once flourished but had remained dormant for more than a century. Since then, their numbers have increased with
Bison were reintroduced to the long-grass prairies thirty years ago, an ecosystem that once flourished but had remained dormant for more than a century. Since then, their numbers have increased with no signs of slowing down.Long ago, herds of Europe’s largest land mammal moved by the thousands through ancient forests. They shaped meadows, spread seeds across entire regions, and created paths that…
In the mountains of central Italy, between Rome and the Adriatic coast, roughly 50 to 60 Marsican brown bears remain. This is the entire global population of the subspecies, which exists nowhere else
In the mountains of central Italy, between Rome and the Adriatic coast, roughly 50 to 60 Marsican brown bears remain. This is the entire global population of the subspecies, which exists nowhere else on Earth. If this group disappears, no other bear population can replace it. The genetic characteristics, behaviors, and thousands of years of adaptation to these Mediterranean mountain ecosystems wou…
In the fall of 2015, a smallmouth bass swam past a stone bridge in the suburbs of Pittsburgh and entered a stretch of Little Sewickley Creek that no bass had reached since the 1920s. The fish was not
In the fall of 2015, a smallmouth bass swam past a stone bridge in the suburbs of Pittsburgh and entered a stretch of Little Sewickley Creek that no bass had reached since the 1920s. The fish was not released there and was not chased into the area. It moved upstream on its own into a shallow section of the creek where an 87-year-old concrete barrier had stood just four months earlier.Little Sewick…
In 1995, the entire population of kakapo, a flightless, moss-green parrot native to New Zealand, numbered just 51 birds. The species was on the brink of extinction. In a final effort to save it,
In 1995, the entire population of kakapo, a flightless, moss-green parrot native to New Zealand, numbered just 51 birds. The species was on the brink of extinction. In a final effort to save it, conservation authorities gathered the remaining survivors and moved them to remote, predator-free islands. The relocation was a desperate measure, and its long-term success was uncertain.The kakapo is an u…
In 1989, wildlife managers released 714 prairie dogs onto a former chemical weapons manufacturing site near Denver. The animals were intended to stabilize soil and control dust on land that had been
In 1989, wildlife managers released 714 prairie dogs onto a former chemical weapons manufacturing site near Denver. The animals were intended to stabilize soil and control dust on land that had been contaminated by decades of industrial activity. That modest assignment initiated a chain of ecological events that eventually supported the release of the black-footed ferret, the rarest mammal in Nort…