Howling into the void? U.S. wolf recovery endangered by Trump

Wolves even manage wetland creation by keeping beavers in check, a study showed last month.

McIntyre has spent decades documenting wolf behavior, particularly at the Yellowstone National Park, where they were eliminated in the 1920s before being reintroduced in 1995.

He found that wolf packs begin when a male disperses from his birth-family to strike out on his own.

Litters are typically four or five pups, and when these grow to be "yearlings," they begin an apprenticeship, honing their hunting skills by watching their elders while learning how to take care of the pups -- much like human teenagers babysitting.

Wolves start their days with warm displays of affection with their pack members, bond through extended bouts of play, and have highly-individualized personality types.

Some are merciful towards rival packs while others are ruthless; some have wandering spirits while others are homebodies; some are serious and others never lose the goofiness of their puphood.

Cooperation is key to survival as their prey, from pronghorns to bison, are often many times larger than wolves, who typically weigh around 80-90 pounds in adulthood.

During their studies at Yellowstone, McIntyre and colleagues found that, contrary to previous beliefs about male leadership, it's the alpha female who decides where the pack dens, where it travels and what it hunts.

"I jokingly sometimes say that's a pretty good indication of their intelligence," he said.

- Breeding programs -

While the gray wolves have regained some ground, the Mexican grays and reds, which both went extinct outside captivity before being reintroduced, are in a far more tenuous position.

A wolf howls at a Wolf Conservation Center on December 6, 2020 in South Salem, New York. [Photo: AFP]

The Wolf Conservation Center participates in a federal program which aims to recover lost genetic diversity through managed breeding, and eventually allow some to resume their rightful place in the wild.

The staff have ways to feed these wolves their roadkill diet without allowing them to know humans were involved -- because habituating to people could prove deadly in the real world.

A few weeks ago, the center sent out two young reds to be paired with potential mates in Tennessee and Minnesota.

"It's always sad for us to say goodbye to them," she said.

"But knowing that they're going to breed, that's got to be exciting for them. Growing up, leaving mom and dad, they can be the boss. So we wish them well."