Wolverine (Gulo gulo)

Half the size of a grizzly but anecdotally twice as ferocious, these large weasels have a reputation of being some of the meanest animals in the park. Labelled as bad-tempered, solitary, and aggressive, wolverines have been said to fight off bears, mountain lions, and entire packs of wolves; they are even believed to possess evil magic – but does their reputation precede them?

With a surprising amount of strength and endurance packed into their small muscular frame, wolverines are competent predators, but they aren’t cold-hearted killers. Like other animals in the weasel family, wolverines are intelligent masters of survival, able to live in extreme alpine environments. They are adaptable, curious, and opportunistic, travelling 30-40 miles a day through rugged mountain terrain in search of small game, carrion, and plants to eat.

Written by Shawna Wolf
Source: https://www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view_article&articles_id=692
PC: Mathias Appel on Flickr https://flic.kr/p/2ixjhA5

Striped skunk (Mephitis mephitis)

Because of the prominent white stripe running down their back, their stinky reputation, and maybe with a little help from Pepe le Pew, skunks are well-known and easily distinguished critters. They are quite versatile, living in woody and grassy habitats ranging from urban areas to wilderness across the United States.

Skunks aren’t the type to look for trouble, but they are equipped with powerful defense in case trouble finds them. When they feel threatened, skunks raise their tail, arch their back, and stomp their front feet in warning. If the threat presses on, the skunk does not turn away. Instead, they bring their rump around, and we all know what happens next – the skunk releases a powerful, odorous spray that can extend nearly 20 feet away, causing quite the unpleasant experience for the intruder. Alongside its obnoxious stench, the smelly substance can cause pain, nausea, and temporary blindness.

Despite this famous defensive device, skunks unfortunately have an extremely high mortality rate, often being killed by disease, predators, or road incidents within their first year of living. Watch out while driving in the park, especially at night when skunks are most active!

Written by Shawna Wolf
PC: Daniel Arndt on Flickr https://flic.kr/p/GeTxnA

Northern flying squirrel (Glaucomys sabrinus)

The northern flying squirrel is a small rodent most commonly found in conifer dominated forests from the treeline in northern Alaska and Canada and down into the middle of the continent in Michigan, Wisconsin, California and Colorado. They can be found in deciduous and mixed forests throughout their range, and while they are not frequently seen or overly abundant, they have been found in the Jackson Hole area and Grand Teton National Park. These silvery grey squirrels inhabit treetops and, as the name suggests, they can “fly” from tree to tree to get around the forest. They do this with a furred patagium which extends from their wrist on the forelimbs to the ankles in the hind limbs. This is very advantageous to them as they are quite clumsy on the ground, so being able to glide from tree to tree and fill up on nuts, acorns, and lichen protects them from becoming an easy meal.

Even if you do happen to be in an area populated with flying squirrels, don’t expect an easy viewing opportunity. As evidenced by their large black eyes, Northern flying squirrels tend to be more active at night making them pretty tough to spot in the canopy for the casual wildlife viewer. Learn more about these rambunctious rodents.

Written by Timothy Uttenhove
PC: Daniel Arndt on Flickr https://flic.kr/p/mtGtPQ

North American Porcupine (Erethizon dorsatum)

Porcupines are best known for their quills: strong hairs that cover almost their entire body. People used to believe that porcupines could use these quills as defensive projectiles; with each porcupine covered in nearly 30,000 quills, that would be a lot of firepower! In reality, porcupines are much less explosive. When they feel threatened, their tough quills stand up on end and easily detach upon contact. In particularly stressful situations, they sometimes run backwards, charging into threatening predators and other animals that get too close.

The natural habitat of porcupines runs from the northeastern United States, up north across much of Canada, and stretches down through the western United States into northern Mexico. They are herbivores and eat pine needles, tree bark, nuts, berries, and other plants. Even though porcupines are common in the area, they aren’t often spotted because they are mostly nocturnal. When you’re driving through the park at night, keep these creatures safe! Be sure to go slow and watch out for them on the road.

Written by Shawna Wolf
PC: Grand Teton on Flickr https://flic.kr/p/K44P49

Boreal Chorus Frog (Pseudacris maculata)

The Boreal Chorus Frog is one of Grand Teton National Park’s most common but also sneakiest residents — they’re small, shy, and exceptionally well-camouflaged. If you manage to glimpse one of these tiny amphibians, count yourself lucky! The only thing that isn’t especially stealthy about them is their loud, locust-like calls. In fact, their scientific genus name is Pseudacris, which means “false locust” in Greek.

These little frogs come out of hiding in the spring earlier than almost any other amphibians. This can be very dangerous for them, as there’s occasionally still snow and ice when they come out. As you can imagine, a little brown frog makes quite a silhouette on powder-white snow, making them an easy early-spring target for hungry predators. In addition, since they come out before many waterways have thawed, their main diet of mosquitos and small insects haven’t even hatched yet! As climate change causes temperature and weather instability in these ecosystems, it’s small players like the boreal chorus frog that suffer greatly as a result.

Written by Shawna Wolf
PC: Timothy Uttenhove

Brown Trout (Salmo trutta)

Even though they’re non-native to the United States, Brown Trout are one of the most plentiful fish in Grand Teton National Park; if you see a nearly invisible shape at the bottom of a stream or river, chances are, you’re looking at one of these common fish. Brown trout are not especially skittish, and if you’re really careful you can occasionally touch one with your bare hands while they’re still swimming. In fact, it’s been said you can even catch one like that, too… Just make sure you have a permit before trying!

These trout are not only valuable to anglers looking for a big catch, they also have advantageous scientific uses. They won’t breed in highly polluted waters, so researchers sometimes observe them to determine the level of pollution in rivers and streams.

Written by Shawna Wolf
PC: USFWS Mountain-Prairie on Flickr https://flic.kr/p/2hpYLxX

Other Sources: https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=931

Lake Trout (Salvelinus namaycush)

Grand Teton National Park (GTNP) is known for its trout fishing. In the park, lake trout are quite the thrilling catch, weighing up to 40 pounds (USFW)! They go by many nicknames – paperbelly, lake char, mackinaw – and are the largest species in their genus, Salvelinus. These fish are non-native in GTNP, but their environmental impact seems to be less drastic here than in Yellowstone Lake nearby.  

The Great Lakes in Michigan and Yellowstone Lake have opposite problems when it comes to lake trout. Overfishing and the introduction of invasive lamprey dangerously thinned the native lake trout population in the Great Lakes in the 1950s. Conversely, lake trout populations exploded after their illegal introduction to Yellowstone Lake in 1980-1990, significantly impacting native cutthroat trout populations and causing far-reaching damage to the lake’s natural ecosystem. Huge efforts in both the Great Lakes and Yellowstone Lake have been made to correct these population counts.  

Learn more:  
https://www.nps.gov/yell/learn/nature/lake-trout.htm 
https://www.nps.gov/articles/non-native-lake-trout-induce-cascading-changes-in-the-yellowstone-lake.htm  

Written by Shawna Wolf
PC: YNP on Flickr https://flic.kr/p/pe6WeX