By Brian Lowry, CNN

(CNN) -- The burgeoning wave of nature documentaries increasingly contains a concerted environmental message: If you enjoy watching these remarkable animals in their native habitats, start thinking seriously about the planet and what humanity is doing to it.

That theme comes across most overtly in "Our Planet," a Netflix series hosted by the great patriarch of the genre, Sir David Attenborough. Produced in conjunction with World Wildlife Fund, the series pushes viewers toward a website "to discover what we need to do now to protect our jungles." at a moment when it has "never been more urgent and important to recognize the fragility of our world."

Discussing the decline of tropical forests, Attenborough notes that they store and capture carbon, cool the planet and provide vital food and medicines. "We lose them at our peril," he explains, while the Wildlife Fund stresses that we have reached a moment when it has "never been more urgent and important to recognize the fragility of our world."

The theme is depicted a bit more subtly but nevertheless resonates in "Hostile Planet," a more crackling, adventure-based documentary series also premiering this week, via National Geographic; and "Dynasties," the recent BBC America look at various species seeking to survive, which also boasts Attenborough's narration.

It is, by any measure, a golden age for nature documentaries, as "Hostile Planet" executive producer Tom Hugh-Jones acknowledged, thanks to the appetite from relatively new outlets, Netflix among them.

Still, Hugh-Jones noted that while "Hostile Planet" wants to convey how the planet is changing, the goal was to weave information into a narrative that stressed a more immersive experience.

"We didn't want it to be a preachy film," the producer, a veteran of the "Planet Earth" series, told CNN, adding that while nature documentaries often draw big ratings in the U.K., "I was really interested in that challenge of trying to reach those more hard-to-reach American audiences."

Toward that end, "Hostile Planet" features more contemporary music and is hosted by Bear Grylls, best known for reality TV shows in which he braves surviving in the great outdoors.

New technology, including drone footage and high-definition photography, has elevated nature documentaries to new heights. Much of the footage in these series is simply jaw-dropping, such as a snow leopard's vertigo-inducing attack on a mountain goat in the "Hostile Planet" premiere.

The themes, however, have also raised ethical questions, including an episode of "Dynasties" in which the filmmakers intervened -- something they are generally reluctant to do -- to help a lion cub that had been poisoned by local farmers. The lions had been attacking cattle, venturing closer to populated areas because of their loss of habitat.

The booming market for nature documentaries comes as concern about climate change and its effects continues to crest.

That environment creates opportunities to be about more than cute animals, with the disclaimer that conveying a deeper message sometimes involves delivering it as stealthily as one of the big cats sneaking up on prey. Either way, documentarians seem keenly aware that they can't ignore, pardon the expression, the elephant in the room.

"Hostile Planet" premieres April 1 at 9 p.m. on National Geographic.

"Our Planet" premieres April 5 on Netflix.