Now 15, he's back tomorrow at 8 p.m. on WHYY TV12 in "Cloud: Challenge of the Stallions," and he's as wild and wily as ever. Half the Western mustangs live in Nevada, but filmmaker Ginger Kathrens turns her cameras (and her heart - she's crazy about these horses) on the intricate equine family relations among the isolated band in the Pryor Mountain Range of Wyoming, east of Yellowstone National Park.

The gorgeous landscape is a major costar, along with various other critters, including mountain lions, who like nothing more for dinner than a sweet foal.

The mustangs are "an exquisite prey species," primarily for the lions, Kathrens said in a phone interview. By the time the horses pass their first birthday, however, they're pretty much safe from predators, except for the most rapacious one, man.

When things were left alone, Kathrens said, "the horses were at zero population growth for four years running. But then the Bureau of Land Management started paying hunters to take the cats out."

So now the BLM is shooting the mares with birth control, and the fertile ones left are responding, as females in dwindling species do, by having more foals, and the whole system is screwed up.

Like most Nature shows, "Cloud" takes a stand for the wildlife. How can it not, in this isolated territory, with these beautiful horses running hither and yon, with an intricate family life that Kathrens says bowled her over?

At the center of the matter are four males, Cloud and Shaman, band leaders, and their sons, Bolder and Flint.

Mustang land is as complicated as Desperate Housewives' Wisteria Lane, though "Challenge of the Stallions" is pretty much G-rated, with only one brief mating scene. As the strong stallions ward off marauding bachelors and corral various mares, Cloud winds up raising Bolder, who's Shaman's son. And Shaman raises Cloud's son, Flint.

The stallions stay with their families year-round, though things go topsy-turvy when the BLM comes calling. Late this summer, using helicopters, it rounded up most of the herd, 146 horses, but then let 89 go, keeping 57 to auction off. Cloud was set free but slightly injured in the process.

Strong lobbying from ranchers, who want the federal land for their 3.2 million sheep and cattle, keeps pressure on the puny population of mustangs. A show like "Challenge of the Stallions" can help balance the battle by igniting public opinion, Kathrens said. "The Oh, Wow! factor is especially big on the East Coast."

Jonathan Storm:

Nature presents 'Cloud: Challenge

of the Stallions'

Tomorrow at

8 p.m., WHYY TV12