The wild ram embodies the mystery and magic of the mountains…
In honor of today’s contest between formidable members of the animal kingdom, I offer this short meander into the world of rams. Methinks the choice of a ram as a team mascot is a wise one – they are sure-footed, brawny, and capable of withstanding hard hits. They also have cool horns that fit nicely on a helmet. Sources claim that going into the 2021 season, the LA Rams were fielding the youngest roster in the NFL. But that had me thinking…how do you age a ram?
On our Yellowstone trip last month, we were lucky to see a few nice specimens of mature Rocky Mountain Bighorn Sheep rams (males). I had heard that you can approximate the age of a ram by counting annular rings on its horns, so that had me searching the internet when I got home to see what I could find. Indeed, there is a lot of information out there, but it seems to me that aging rams by their horns is somewhat of an art form. I present below what I have gleaned from a variety of web resources.
Unlike the antlers of members of the deer family, the horns of bighorn sheep continue to grow throughout their lives (they are not shed). Similar to tree rings, the growth varies during the year according to conditions like favorable nutrition. Winter is the time of stress for Yellowstone bighorns (mating season is early winter and food resources are more limited in winter), so growth slows considerably, resulting in an annular ring. Growth is typically fastest during the second year, resulting in a wide spacing between the first and second rings. It slows with age, so rings tend to be closer together toward the base in older rams. Rams reach sexual maturity at about 4 years, and one reference said that in most rams, the 4th year ring will be the most distinct (darkest, deepest). The first year of growth is often obscured in older rams as they have what are called broomed horns (broken tips) from battering against other rams during the mating season (bighorn sheep rams dual with each other for mating dominance by ramming their heads together to see who is the strongest). So, looking at the ram below, it looks like part of the first year has been obliterated (broomed) and then moving from the tip up, you see a fairly dark ring after a lot of growth. I think that is the second year ring. Then it gets a little harder, but, if you go with the darkest ring being the 4th year, you can see a dark ring before you get to the top of the curl.I see two other dark rings after that, with perhaps a new ring forming near the base. So, I’m guessing this is a 7-year old.
I cropped this picture and turned it into black and white to see if that helps highlight the rings any better. I labeled what I think are the annular rings. Just to make things more confusing they do have what are called false rings. You are supposed to look for rings that go all the way around the horn (something difficult to do without the horn in hand). This is how wildlife biologists estimate age (although the best method is to extract a tooth and count the rings).
Below are two more Yellowstone rams. What is your guess as to age? My estimates are at the bottom of the post. Start with which do you think is older, Ram A or B?
On Ram A, you can see a noticeably dark ring. If that is the 4th year, then I estimate Ram A to be at least 7, and maybe as much as 10, though the lighting and distance of the photo make it particularly hard to tell. Ram B seems to have more distinct rings. The 4th year looks like the ring near the top of the curl. The 5th year ring is next and also quite distinct. But I think the next two dark lines are false rings. Compare the rings in the horn on the left of the image with those on the right. You can see a couple of those dark rings do not go all the way around the top of the horn (look for grooves). I am guessing this ram is about 6 (almost 7). If I’m right, then Ram A is older than Ram B. See labeled diagrams below for my estimates.
But, as I said, these are my best guesses, If you want to test your skills more, see these references:
It certainly is an art form, and most people say you can get it to within a year of the ram’s actual age using this method. Now, I’m not sure about ageing Bengal Tigers…maybe the number of stripes divided by the age of the quarterback?
Ungulates. The most boring animals on earth. All they do is stand around and chew their cud.
It seems there are not a lot of quotes out there about ungulates (hoofed mammals) but I found this one in a clever blog post by someone that I know through social media. I agree with him, that ungulates often get overlooked by a lot of people when there are charismatic mega-fauna like wolves and bears around, but they shouldn’t be, as they are fascinating and beautiful in their own right. Yellowstone has eight species of ungulates (hence the title), seven native to the region (Elk, Bison, Mule Deer, White-tailed Deer, Rocky Mountain Bighorn Sheep, Pronghorn, Moose) and one introduced to the area (Rocky Mountain Goats). On this trip, we managed to see the seven native species. It isn’t easy to spot a white goat high on a mountain slope in winter! Not many years ago, the toughest two of the ungulates to find in the park were Moose and White-tailed Deer (Mule Deer are the dominant of what are usually considered deer in the park). But, the past few years we have been seeing more of our familiar white-tails, and this year, was a relative banner year for Moose (more on them in a future post).
Here are some tales (and tails) of some ungulates we observed…
Many of these grazers move to lower elevations in winter due to the usual heavy snow in much of the park.They tend to congregate in the Northern Range due its lower snow pack and in areas near or beyond the North entrance at the town of Gardiner, MT. Indeed, one of the hazards of staying where we did, several miles north of Gardiner, was that we had to run the gauntlet of roadside Elk every morning and evening in darkness (definitely not a critter you want to encounter with your vehicle). These large members of the deer family undoubtedly gain another advantage by relocating to these areas in winter as there are probably fewer wolves due to the human presence (although that means they do encounter hunters).
The town of Gardiner lies in a rain shadow area and is below 6000 ft in elevation, so it tends to have milder winters than most of the park. It is amazing to me how the wildlife adapts to the town (and vice versa). One example is the use of the school’s athletic field as a hangout and grazing spot for Elk, Bison, Pronghorn, and a variety of other critters. I like to think that one unique form of detention at this school involves going out to the field and removing the scat piles before a game.
One ungulate, in particular, tends to leave all but the lowest elevations of the park (near the North entrance) every winter – the Pronghorn. Though they are common in Lamar Valley in summer, they all migrate over 25 miles to spend the winter near Gardiner or even farther north. Deep snow makes it difficult for them to browse and greatly diminishes their primary defense against predators – their speed. They are the fastest land mammal in North America, reaching burst speeds of a little over 60 mph and capable of sustained speeds of 45-50 mph. This makes them the second fastest mammal on Earth, second only to the Cheetah (but Pronghorns can keep up a fast speed longer than a Cheetah). Their large eyes are located on the sides of their head to allow for all-around viewing. And they have a large (for their size) heart, windpipe, and lungs, allowing them to get plenty of oxygen and blood supply for their high-octane movements.
Since vision is such an important trait for Pronghorns, and since they live in herds in open habitats, they have another communication signal used to alert other herd members of danger. If a Pronghorn sees a predator, it raises the white hairs on its rump, making a large white patch visible for considerable distances. They also release an alarm odor from glands on the rump (it supposedly smells like buttered popcorn – probably why you never see Pronghorns at the movies…they would be freaked out all the time).
Below is a Pronghorn rump in action…
I stayed in my car and spent about 45 minutes watching the Pronghorn feed. This is what I really like to do – watch wildlife going about their daily lives. Staying in your vehicle or sitting quietly helps wildlife feel more at ease and allows them to continue feeding, or doing whatever, undisturbed.
Along the same road, there was a large group of Rocky Mountain Bighorn Sheep grazing at the foot of the ridge-line. Many photographers stopped to get photos and one grpup, unfortunately, hiked over to the base of the ridge and obviously disturbed the herd as they moved up the slope. I saw this behavior way too often in the park this time.
On another drive down this road, I had to stop to let a small band of ewes and young cross the road in front of me. I managed one portrait as they sauntered across.
Among the most photographed animals I saw on this trip were a group of bighorn rams hanging out at the usual small cliff near the confluence of Soda Butte Creek and the Lamar River. This is consistently a good spot for sheep in the winter as I guess the small steep rock face provide just enough protection as an escape from potential predators like wolves. The cliff is a short walk from a pullout and you can get decent images from the roadside, which doesn’t seem to bother the rams at all. Here are a couple of examples…
More on the magnificent horns of these rams in a future post.
Finally, a few images of the iconic Bison, America’s National Mammal (designated as such with the passage of the Bison Legacy Act in 2016). It joins the Bald Eagle as a national symbol and represents an amazing comeback from the brink of extinction. Bison numbers went from an estimated 30-40 million roaming North America in the early 1800’s, to fewer than 1000 individuals less than 100 years ago. The causes of this precipitous decline included uncontrolled market hunting (Bison hides were highly valued) and a concerted effort by the U.S. military to remove Native American tribes from the land by taking away their main food source: Bison. Some Bison found protection on private ranches, In Yellowstone, the numbers dwindled to about 24 Bison that survived deep in the park’s interior. In one of the first efforts to try to restore a wild species, park officials in Yellowstone began to manage the remaining herd and enhanced it with wild Bison purchased from private owners. The herd was ranched in Mammoth and then in Lamar Valley at the Lamar Buffalo Ranch. Today, the park’s herd numbers about 5000. More information on Bison and the history of management in the park can be found here.
I have always had an affinity for Yellowstone Bison (I blame the movie Dances with Wolves), so I try to spend some time alone on each trip with these iconic creatures. I managed to spend over an hour one day with two large bulls, watching them feed in a picturesque valley below the towering Baronette Peak. Snow was falling, and then patches of blue sky would appear, and then more snow. None of it fazed the Bison as they plowed through the snow with their massive heads.
I’ll end with one of my favorite teacher quotes from my museum workshop days, penned by Donna, after spending time observing a herd in Lamar Valley…
What must it be like to be a Bison, to own nothing yet have everything?