Hormones turn Groucho, the Peyton Manning of Denver Zoo elephants, into Richard Sherman

Groucho is usually the Peyton Manning of elephants, "a perfect gentleman," says Denver Zoo large animal curator Dale Leeds. In his view, "Groucho is a mature male with self-confidence," not unlike the Broncos's seasoned quarterback. "Peyton Manning doesn't have to get on TV, scream and shout about how great he is, scream and shout about how everybody else is bad. He knows he's good. He doesn't have to sell it."

But when Groucho is in musth -- as he was from late August until very recently -- it's a different story.

What is musth? In our 2009 story about the Denver Zoo's new elephant exhibit, we described it as "a very special time in a male elephant's life, a time worthy of its own young-adult novel, something with a title like Are You There, God? It's Me, Ranchipur."

Musth is characterized by elevated hormone levels, heightened sexual interest and aggressive activity. It can last anywhere from a few days to several months. During musth, the glands on either side of a bull elephant's head leak fluid, his penis dribbles urine and, Leeds says, "the penis and sheath get a green tinge to it" -- sometimes known as green weenie. Musth bulls also emit a smell that Leeds describes as "bad musk cologne from the '70s. Strong, pungent -- it smells like testosterone."

We imagine it to be something like this:

At 43 years old, Groucho is the oldest of the Denver Zoo's three male elephants. He was born in the wild and arrived at the Bronx Zoo in New York in 1973. In 1986, he moved to the Fort Worth Zoo in Texas and in 2012, he arrived in Denver. Though the Denver Zoo doesn't know why he was named Groucho -- he isn't grouchy, staff insist -- they suspect it was a tribute to comedian Groucho Marx, who famously told a joke about an elephant:

The zoo also has two younger bull elephants, nine-year-old Bodhi and six-year-old Billy. The zoo's $50 million elephant exhibit, Toyota Elephant Passage, opened in 2011 with the capacity for twelve elephants, eight of which could be male. That makes the exhibit unique; most zoos keep a majority of female elephants because they're smaller and easier to handle. (The Denver Zoo also has two lady elephants, Dolly and Kimbo.) The boys -- because of their size and, of course, their musth -- can be trickier.

Continue for more on Groucho and his musth, including more videos. When he's not in musth, Groucho is easy-going and self-assured. In other words, if he were a football player who'd just won, say, a big championship game, he'd dress up in a suit and tie and calmly charm the press corps with a witty quip like this:

Younger males, on the other hand, "are a little bit more similar to oh, say, an unnamed Seahawk player that has to be outrageous, over-the-top and try to make himself to be something better than he may actually be," Leeds says.

Could Leeds be referring to Seahawks cornerback Richard Sherman? You be the judge.

A mature bull in musth can be a whole different animal -- more Seahawk-like, if you will. When he was in Fort Worth, Groucho was on a regular musth schedule, Leeds says; the zookeepers there knew when to expect it and they prepared accordingly. But after arriving in Denver, Groucho's musth-timing got shaken up a bit. The time of year when he usually went into musth came and went, Leeds says, and it wasn't until last July and August that keepers began to notice that Groucho was getting "ramped up" and "irritable."

At the height of his musth in late September, Leeds says, Groucho would work out his aggression by blasting water at the keepers and hitting the bars and gates in the elephant barn, an 18,000-square-foot building with eight stalls for the animals. "He just makes a big deal about himself and how tough he is," Leeds says.

But the keepers didn't keep Groucho indoors the whole time, Leeds says. Instead, they managed his musth day by day. If he was having a particularly irritable day, Leeds explains, they'd keep him in an area in the back of the elephant barn. If he was having a calmer day, they'd put him in one of the outdoor yards closest to the barn so he could roam around -- but also so they could easily move him back indoors if need be.

"It's something to behold," Leeds says of a male elephant in musth. But, he adds, it's also "completely normal" and Groucho's behaviors were typical for a musth bull. "We're always very safe with the elephants but we have to be doubly safe," Leeds says.

One of the most alarming things for the keepers is how much weight a musth bull loses, Leeds says. Groucho, who came to the Denver Zoo in early 2012 weighing 11,000 pounds, lost a full 2,000 pounds during his musth. The weight-loss isn't harmful, Leeds explains. In fact, it's normal; a bull with that much testosterone pumping through his system generally has one main thing on his mind -- and it isn't eating.

Which made us wonder: How did the females fare during Groucho's musth? The answer, Leeds says, is that because both Dolly and Kimbo are post-reproductive, Groucho basically ignored them. "It would be different if the adult females were cycling," Leeds says. "And I think it will become different as our young males become more mature."

In the wild, if two mature male elephants in musth come across one another, they will fight -- sometimes violently -- to establish dominance and breeding rights. "I don't want to be too anthropomorphic about this, but I think...if there was another big bull in here, he might want to really fight," Leeds says. "But with the two young males, he's like, 'This is not even worth getting out of bed for. There's no challenge there.'"

Because he's freaking Peyton Manning.

Below, watch a video of (non-musth) Groucho in the elephant barn.

More from our News archive: "Denver Zoo tamandua Rio is pregnant: Watch a video of the anteater's ultrasound."

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