Arctic seals are being pushed closer to extinction by climate change and more than half of bird species around the world are declining under pressure from deforestation and agriculture, according to an annual assessment from the International Union for Conservation of Nature.

One bright spot: green sea turtles, which have recovered substantially thanks to decades of conservation efforts, the IUCN said Friday as it released its annual “Red List” of threatened species.

Since the IUCN report is a global assessment, it captures success stories on a large scale, like the rebound of green sea turtles across the world's oceans. 

That's a bright spot, experts say, because it shows how human intervention, through strict legal protections against hunting and through other conservation programs, can make a difference.

Still, "it’s important to note that conservation efforts of sea turtles can take decades before you realize the the fruits of that labor,” said Justin Perrault, vice president of research at Loggerhead Marinelife Center in Florida, who was not involved with the IUCN report.