What's That Scat? (2024)

4 minute read.

As we are out enjoying some of the many trails the Yukon has to offer, we often have to watch our step to make sure we’re not putting our boots in something smelly! These unexpected trail obstacles can be great indicators of whose habitat we are walking into, what they are eating, and how they are digesting it. Just like us, many animals have dynamic diets, and will eat what is available. Scat can be interesting but can also spread diseases, even to humans, so it should be looked at and not touched, especially by our furry companions.

Light brown bear scat with seeds visible.

Bears are relatives of mammalian carnivores, they have a digestive system similar to carnivores, without a cecum or extended large intestine. This limits how efficiently they can process leafy plant material and they must eat a lot if they are relying on these foods, which is common in the spring. As a result, when a bear eats a lot of plant material their scat often has a green tinge from the undigested grasses or a fibrous appearance. Typically, their scat is brown or black and tapered, though sometimes it can appear as more globular if it is loose. Grizzly scat tends to be a bit wider and larger piles than black bear scat. It can be hard to distinguish between the two, but both should make a hiker cautious of the trail ahead. Remember bear spray and noisemakers and stay bear safe!

Left to right: Older bear scat; bear scat that is darker brown in colour with grasses visible.

If you’re interested in getting involved in bear research, the Operation Ursus Research using Scat (OURS) project is aimed at estimating the Yukon grizzly and black bear populations using DNA available in bear scat. Lucile leads the study and shares the project story Bear Poo and You with YWP.

Wolf scat with fur visible.

There will likely be much less of it as well. Foxes often defecate in obvious areas to mark their territory. The Wildlife Preserve exists as an ecosystem within a larger ecosystem and foxes are one of the many wild animals that visit. They seem to like to use the boardwalks at the front cabin to do their business!

Lynx scat of varying ages among grass.

Their scat is black, tubular and tapered, and does not have so much undigested material as the bears or canines. It is also very smelly. Like a house cat, they will cover their scat with dirt or snow, probably to hide their presence from nearby animals. Also like house cats, they often defecate in the same latrine over and over, which can be seen in our lynx habitat.

Lynx, like house cats, often poop in the same places every time. This is one of the latrines in the lynx habitat at the Preserve.

From left to right: Caribou, moose, mule deer and elk. Photo Credit: L.Caskenette & J.Paleczny.

Their diets are often high in fibrous, dry tree materials like leaves and twigs, which is why their feces forms pellets. If they are eating more grasses, in the summer, it may appear softer and more clumpy. Cervids are all ruminants which means that their stomachs have four compartments: the rumen, the reticulum, the omasum and the abomasum. This allows for fermentation by bacteria and other processes that break down vegetation. This is part of the reason that cervid scat does not have as much undigested material as the carnivores’, despite their plant diet having less digestible material. In addition, they will regurgitate their food and chew it again, also called chewing their cud!

Left to Right: Soft caribou scat clumps together versus caribou scat in pellet form.

Deer pellets are small, about 1 cm in diameter, and are left in piles of many pellets. They defecate an average of 13 times per day! Elk scat is similar but 1-1.5 cm in diameter, and moose scat is even larger at 1.5-2 cm in diameter. Deer and elk pellets are rounder than moose pellets.

Softer deer scat often clumps together as seen here.

Moose are more strictly browsers, that eat only tree materials, so mostly their pellets are harder. Caribou scat appears somewhat more rough than deer or moose scat. It is often in harder pellet form in the winter when they eat a lot of lichens and sedges. In the summer, when their diet switches to grasses and vegetation with a high moisture content, their scat often forms larger soft clumps.

Moose scat in pellet form, darker brown because it’s older.

Left to Right: Muskox, bison, mountain goat, thinhorn sheep. Photo Credit: L. Caskenette

Muskox, mountain goats, and thinhorn mountain sheep also form pellet scat, even when their diets consist largely of grass. That’s because their digestive tracts are highly evolved to reabsorb as much water as possible, likely an adaptation to their arid alpine (goats and sheep) and tundra (muskox) habitats.

Sheep scat forms pellets.

Goats have varied diets that includes browse, shrubs, lichens, grasses, and even trees. Their alpine foraging sites may be sparse, which doesn’t allow them to be picky eaters. Muskoxen eat grasses, forbs (herbaceous flowering plants), and willows, which they often have to dig out from the frozen arctic ground by smashing the permafrost with their heads and pawing the ice pieces out of the way. Mountain sheep eat mostly grasses and some other low growing sedges.

Muskox scat.

Bison scat is distinct from all the other ruminants mentioned above, because it forms an indistinct pile. Their diet is also primarily grasses and other low-lying herbaceous plants, but they may eat some willows and twigs. Grasses would make their scat more loose, but we’re taking suggestions for what makes their scat so different from the other grass-loving bovids!

Bison patty.

Hopefully after hearing all of these scat facts you can see scat as more than just something gross to be avoided on the side of the trail. It can tell you who’s habitat you are in, but also what they have been eating. It is interesting to watch it change throughout the season. Of course biologists may be able to find out way more about an animal through their scat, for instance genetic samples or presence of pathogens. There is so much to learn from the scat around us!

Photo Credit: Sophia Slater or as otherwise credited.