October 2020 Wildlife Log
Fall is in full swing across the Greater Yellowstone Ecosystem. Check back often for the latest video and photos from October 2020 in Grand Teton and Yellowstone National Parks!
Hyperphagia, why Bears Get Fat for Winter
It's been an amazing fall of bear watching in Grand Teton and Yellowstone National Parks. By late October, most black bears have headed to dens to sleep away the harsh winter months. Grizzlies however are still very much out and about, we've observed active bruins all the way into late December in some years! It takes a lot of work to put on enough fat to survive winter and earlier in the fall our most famous park bear, Grizzly 399, was looking a bit thin. We're not too surprised, considering this senior citizen has been raising four cubs all summer long! As guide Sarah Ernst (@sernst83) reports, the quintet has since put on some pounds and is fast getting ready for hibernation.
How do bears sleep for upwards of five months, only to emerge fit and healthy? All fall, grizzly 399 and her cubs have been eating constantly, building up “brown fat,” a specialized fat which can be quickly converted to heat and energy when needed and also acts as a great insulating layer. Brown fat is less common in adult humans but is found in newborn babies, helping to keep them warm when adjusting to their new world after being born.
While staying toasty warm underneath all of that warm fat, hibernating bears also conserve energy by reducing waste products. Instead of expelling waste nitrogen in urine, they reprocess it, converting it back into muscle mass. Come springtime, bears awaken fresh and ready to take a a stroll for their first meal in months.
Beyond Old Faithful, the Diverse Geysers of Yellowstone
For most first time visitors to Yellowstone, no trip is complete without an Old Faithful eruption. The impressive and predictable eruption is a quintessential Yellowstone moment, yet this iconic feature is but one of many impressive geysers in the park. With over 10,000 active thermal features, there is a lifetime of hot pools, mud pots, fumaroles, and geysers to enjoy in the world's first National Park. Ecotour Adventures Guide Mike Vanian has had a busy summer of “Geyser Gazing” watch the video to learn more about these diverse and fascinating phenomena which led early visitors to describe Yellowstone as “Wonderland.”
Geyser Facts
- With eruptions reaching 300 feet high, Steamboat Geyser is the largest geyser in the world. After years of dormancy, Steamboat has become much more active in recent years, erupting over 100 times since March 2018!
- Superheated water inside geyser vents can reach temperatures of over 240 degrees Fahrenheit before flashing to steam and causing an eruption. The boiling temperature in Yellowstone (7500' feet) is about 198 degrees F!
- Liquid water expands to over 1500 times its original volume as it flashes to steam, which can cause catastrophic explosions.
- Yellowstone is home to around 500 geysers, more than half of all geysers found on Earth!
Fall Photography Workshop Highlights!
Last week we wrapped up our 2020 Fall Photography Workshop with Sony Alpha Photographer Nate Luebbe (@nateinthewild). Fall is one of our favorite times of year for wildlife activity and scenic landscapes and this year didn't disappoint! Watch the video to enjoy some of the following highlights and more!
Great Gray Owls - Sometimes called the gray ghost due to their elusive nature, we were fortunate to get some great shots of a great gray owl hunting during this tour. By October, great grays have fledged and are out hunting on their own, though some juveniles might still beg to see if any adults are around. Great grays stand at about 2 feet tall, making them the largest owl by volume in North America. But don't let the floof fool you, these raptors weigh less than the smaller great horned owl!
Grizzly 399 and Cubs - Early on in the workshop we watched as grizzly 399 and cubs walked down the road right towards us before heading to a foraging spot across the Snake River. The family has been busy foraging on edible berries and has put on some weight, we're hopeful they will enter winter hibernation in good shape. It isn't uncommon for grizzlies to remain active in Jackson Hole through November and even into December!
Bugling Bulls - The elk rut has been amazing this year across the Greater Yellowstone Ecosystem. We had multiple opportunities to watch bulls bugle, strut, and spar in an attempt to out-compete one another and draw the attention of nearby cow elk. In Mammoth, we watched as a tired old bull, missing two of his tines finally gave up, retreating from a younger fitter male who stole the show right in front of Officers Row.
2021 Dates October 1st - 9th!
Video: Black Bears vs Grizzly Bears
Why do black bears climb trees so much? In addition to getting all those tasty berries, it might also have something to do with needing to flee from bigger scarier bears! In the Greater Yellowstone Ecosystem, black bears have to contend with grizzlies, who given the chance will kill and eat them. Thankfully for black bears, their cat claws and preference for forested habitats means they are able to quickly escape should a grizzly approach.
This adaptation is thought to have arisen from not only the presence of grizzlies but also short-faced and cave bears, giant Pleistocene bruins who stood 6' tall at the shoulder! These bears are now extinct but black bears remain in the woods and are for the most part quite docile. That's why black bears are found all over North America, including in close proximity to humans.
Grizzlies by contrast have always been more of a plains animal, and their response to the giant Pleistocene bears was to get scrappy. By being aggressive, grizzlies proved themselves not worth pursuing by the larger bears, and were able to survive living on the same landscape with them. This is the likely explanation for why grizzlies are more likely to attack humans than black bears. (learn how to effectively carry bear spray here!)
Guide Sarah Ernst talks more in-depth about the two species in this short from our recent Wildlife Wednesday Weekly Round-up, check it out!
