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The Problem with Yogi Bear in Your Picnic Basket

Authors: Chien, Shukla, Stephens, Tyre

From Smokey the Bear to Yogi Bear, all the way to the California state flag, everybody knows what grizzly bears are. They are indistinguishable animals, symbolic of many American ideals. Even though grizzlies are so recognizable (and cute), their numbers have been brought so low that they are classified as an endangered species. About 150 years ago in California, there used to be about 10,000 grizzlies roaming around in their natural habitat. By 1922, all of these furry friends were wiped out. As a result, their natural habitat has shifted north, mainly into Canada and Northern U.S. where there is a lot of untouched land. Humans are now expanding into those regions, disturbing that once pristine land.
 Grizzly bears are found across Northern Europe, Northern Asia and North America. They live in the arctic, boreal forests, transition grasslands, coastal forests, and mountain forests, showcasing their versatility. As omnivores, grizzlies have a very diverse diet, although they mainly eat salmon, trout and berries.  When feeding on fish they leave the carcasses on land, allowing for all of the nutrients to decompose into the soil. When foraging on berries and ground squirrels, they overturn the soil, and in turn replenish the topsoil. Both of these actions are crucial to a healthy forest, as they naturally fertilize the soil.

Human-bear interactions are increasing, and while this is great for ecotourists, it's not so great for bears. Human-based activities leads to higher numbers of stressed bears and a lower number of cubs each year. Having one of the lowest reproductive rates in North America, fewer cubs each year could not only lead to a grizzly bear population collapse, but a collapse of the whole of Western Canada’s landscape. 

 

Human Impacts

 Alberta has many extraction sites, wells, logging sites, and other human areas that could be dangerous to bears. Surprisingly, the bears that are captured near extraction sites have good overall body health. Scientists think this happens because extraction sites tear down thick parts of the landscape, giving bears access to rich food (1) that they could not have gotten otherwise. Constant food supply is one of the biggest factors in grizzly health, which they can get in these disturbed areas. Because of the need for constant food, grizzlies don’t do as well in areas where veggies only grow in the winter or spring, they need access to annual plants to truly thrive. 

Even more shocking, the grizzlies inside a natural park were found in poorer health than the ones near the extraction sites! The parks are situated on mountains, and while it was a good effort to set aside land for grizzlies, they set apart the wrong type of land. This park’s plants vary tremendously by season, so the grizzlies could not get the constant food supply that they needed.

But wait! That is just looking into body condition alone. There is an even more telling factor that trumps body condition: long term stress. To test for this, researchers looked at a hormone found on bears’ hairs called glucocorticoid (2). This hormone tells you how stressed a bear is, as well as how much fat a bear has. A stressed bear is not going to spend as much time mating, foraging for food, and spending a good amount of its energy just watching its back. Bears found near human-based sites had extremely high levels of long term stress, and this increased even more in mother bears. Because of their stress, mother bears started having fewer cubs, and when they did have cubs, those cubs had a lower chance of survival. On top of that, grizzly bears that are closer to humans have a human higher death rate. We can blame this on guns, car accidents, or any other sort of method to get bears away from our endeavors. A calmer, plumper bear is more likely to produce more cubs and be able to survive natural disasters, periods of starvation, disease, or other events that it could come across in the wild.

 Weighing all the pros against the cons, grizzly bears in wild, untouched sites come out on top. While individual bears captured near human sites were in better health, the impact on their population was far worse.  

 

Ecology and Conservation: What can you do?

 In order to save this important species, we must learn to love having unexpected neighbors. Grizzlies suffer the most when they interact with humans, with our natural tendency to try and get close to animals leading to the endangerment of both grizzlies and humans. Currently, there are some planned conservation efforts that show a lot of promise. Once these concepts are set in place, bear habitats will have increased security with the help of spatial mapping, allowing the bears to avoid people while reaching their daily energetic requirements. In addition, specific locations will be marked as a “linkage zone” which will act as a safe passage and temporary homes for grizzlies(3). In turn, bears can spend less time looking over their shoulders and more time scratching their backs on trees.

There are many preventive measures that can be easily taken to ensure as little contact between us and the bears. One example of this that is a little bit dividing, is the use of electric fences. Both humans and bears are not too fond of being shocked, so it separates the two effectively. The two downsides to this are the cost and the fact that both grizzlies and humans don’t want giant fences that shock you in our backyards. Even though there has been pushback, the use of these electric fences is extremely effective and is growing in popularity.

As the great explorers we are, we love camping. More than camping though, we love eating good food. Usually, there is no problem when these two things overlap, but when you camp in areas with bears around, problems arise. Bears want to eat your food more than you do, which leads to some awkward standoffs. If grizzlies become used to stealing our food, they become worse at finding their own. This leads to bears getting food-conditioned, and they become more standoffish with humans, which can sadly lead to euthanasia. To prevent this, food storage lockers are being installed at campsites, and fences are being put up around dumps, but these are both costly.

 Although both of these solutions are effective, they will not bring the population of grizzlies back to a healthy state. One proposal that is highly controversial, is bringing grizzlies back to parts of their previous ranges. Conservation groups are petitioning to reintroduce grizzly bear populations across the United States (4). The Center for Biological Diversity, a government group, has already identified around 110,000 square miles of suitable habitat for grizzly bears to be reintroduced across California, Arizona, and Utah (5). The conservation of grizzly bears would allow for the preservation of a key species not only within their ecosystem but also within our culture.

 Although this reintroduction would help bears and their environment, people have not exactly jumped with joy when they hear about it. In fact, in 2014, the U.S. Fish and Wildlife received a petition to bring grizzly bears back to California, but swiftly rejected it. It’s easy to see why they immediately said no, but reintroducing them could lead to higher biodiversity, and a healthier ecosystem. 

 Back in 1995, Yellowstone reintroduced grey wolves back into their park, and reaped the benefits. Wolves reduced the numbers of deer, which let the trees grow back, sing the number of birds that lived in the area, and with the trees, beavers came back. All of this happened in less than 20 years, and it was all unexpected. If grizzlies are reintroduced into the natural environments, the effects they would have on their environment could be untold. However, these effects might not ever see the light of day. With human-bear interactions on the rise, the population of grizzlies has been declining until recently. Although the amount of habitat is increasing, the change is not large. To make a big difference, we need to take all measures possible, especially reintroduction. 

For too long we destroyed their habitats in a blind effort to benefit humanity, but we rarely stop to look around at the consequences. Humans’ natural tendency to explore the great outdoors leads to fragmentation of vital land. Decreasing our interactions with grizzly bears is a high priority, as the stress we cause has many detrimental effects. Setting aside undisturbed land, using electric fences, putting up food storage lockers and establishing zones within their habitats will all help tremendously to conserve this species. However, if we really want grizzlies to thrive, reintroduction is one of our best options. Although controversial, this act would help increase the diversity of genes, and could even come with a cascade of positive effects on their environment when reintroduced. With everyone’s help, we can help lead the iconic grizzly bear back to its former glory.

 

Literature Cited

  1. Bourbonnais, M. L., et al. “Environmental Factors and Habitat Use Influence Body Condition of Individuals in a Species at Risk, the Grizzly Bear.” Conservation Physiology, vol. 2, no. 1, 2014, doi:10.1093/conphys/cou043.
  1. Cattet, M., et al. “Quantifying Long-Term Stress in Brown Bears with the Hair Cortisol Concentration: a Biomarker That May Be Confounded by Rapid Changes in Response to Capture and Handling.” Conservation Physiology, vol. 2, no. 1, 2014, doi:10.1093/conphys/cou026.
  1. Mclellan, B. N., Woods, J. G., & Proctor, M. F. (2004). Estimating Grizzly Bear Distribution And Abundance Relative To Habitat And Human Influence. Journal of Wildlife Management, 68(1), 138–152.
  1. Center For Biological Diversity. (2014). “Petition for a Recovery Plan for the Grizzly Bear (Ursus arctos    horribilis) Across Its Native Range in the Conterminous United States”
  1. Greenwald, Noah. (2014).  Legal Petition Calls for Return of Grizzly Bears to Vast Portions of American West. Center for Biological Diversity. https://www.biologicaldiversity.org/news/press_releases/2014/grizzly-bear-06-18-2014.html

 

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