Grizzly Bear - Brody Gill
GRIZZLY BEAR (Ursus Arctos Horribilis)
By, Brody Gill
Descriptions and Ecology
Overview
The Grizzly Bear, often called
the North American Brown Bear, is a subspecies of the Brown Bear (Ursus Arctos)
that can reach over 10’ tall and weigh several hundred pounds. They are typically
larger and more aggressive than the average Brown Bear with large concave faces
and a distinct hump above their shoulders. Their name comes from their long,
white tipped hair that gives them a “grizzled” look. Most Grizzlies are dark
brown, but their coat can often range from being near black to a light cream
color. They also have sharp claws that can grow to 4 inches long which help
them with digging and catching fish. However, Grizzly Bears are omnivores and
like to feast on things such as berries and salmon. When their food supply gets
low, Grizzlies go into hibernation for as long as six months.
Habitat
The Grizzly Bear has historically
roamed all over the western half of North America. Ranging from Mexico to Alaska
and from the Pacific Coast to as far east as the Mississippi River. Furthermore,
they have a large range of habitats they like to occupy. Places such as: artic
barren grounds, prairies, foothill grasslands, and thick temperate rainforest. Grizzly
Bears generally have a home territory that they mostly stick around, however,
their territories often overlap with other bears’ territories. Most male
Grizzlies have a larger range of territory than females do, allowing males to
take advantage of the best food options in their territory.
Social Structure
Grizzly Bears are very much a
K-Selected species, meaning that they have only a few offspring a year, take
considerable care of their young, are large bodied, have a long life
expectancy, etc. While they do not usually live in groups, Grizzly Bears can be
seen around other bears when the food supply is abundant. They are generally
solitary mammals that have a territory they range. Males often “rub” trees
leaving their hair and scent on the tree to show where their territory is so
females can more easily find them come mating time. Grizzlies have one of the
slowest reproductive rates waiting until four or five years old before they can
reproduce. Females are very protective of their young for two or three years,
often becoming much more aggressive during this time.
Diet
Most animals at the top of the food chain are mainly carnivores. However, while Grizzlies are on top of the food chain, they are omnivores meaning that they both eat meat and vegetation. Their choice of food varies widely, including: roots, berries, fungi, grasses, insects, elk, deer, salmon, trout, and dead animals. In the spring, Grizzlies generally like to feast on any meet they can find to give them protein. During the summertime, they try to eat several types of forages or fruits. Finally, in the fall, before they go into hibernation, they try to gain as much weight as possible by eating roots and nuts. Although, they have a vast variety of food they will eat, vegetation consists of about 90% of their diet. Their diet also helps the ecosystems that they live in by regulating grazing and populations of other animals.
Population Changes
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgY4N9E8ZXy9qyLjY6k6xNk8OHK67JK2n2nQeVT0FouxcaIxrlZn_rCZdHcX8htwgU0eD1XTH8ke5SKvFMSd1P6tB0g-sJS0MNd05I_CkawrX6ujmBAAnWj9X_xBzAG4kJfyuZpgLAqf7z1/s400/The-Bears-2-1.jpg)
Geographic Changes
As said above, Grizzly Bears once
roamed most of North America. However, throughout history, their geographic range
in which they live has shrunk considerably as seen in the graph on the right. Today,
they can only be seen in a couple of states in the lower 48 states where they are
on the endangered species list. Most of the population of Grizzly Bears live in
the Greater Yellowstone Ecosystem. However, they do live in other parts of Montana,
Wyoming, Idaho and even a few have been spotted in Washington. The largest
reason that bears have been extirpated from their historic territories is primarily
because of humans. Through human development and conflict, to habitat destruction,
and of course climate change, bears have had to relocated to find sustainable
food and habitat for them to live in.
Listing Date & Type
The Grizzly Bear was officially listed
as a threatened species in the lower 48 states on July 28, 1975. However, there
was no official recovery plan for the species until 1993. Until this time,
Grizzly Bears populations had been steadily declining. In 2003, the recovery
plan goals issued from 1993, had been met for six straight years. In 2006,
there was a revised recovery plan for the Grizzly Bear issued. After this recovery
plan went into effect, Grizzly Bears bounced back and forth from being on the “Threaten
Species” list in several controversial lawsuits. As of March 2017, they are no
longer considered a threatened species in the Greater Yellowstone Ecosystem,
but still are in the rest of the lower 48 states.
Cause of Listing
Some of the initial causes of Grizzly
Bears being listed on the “Threatened Species” list is through human conflict.
This includes things such as human development and habitat destruction. During
the times that Grizzly Bear populations were declining, humans were developing
more land to put houses on in rural areas. This being their home, Grizzlies
would often start coming up to house to dig in their garbage or dig in people’s
gardens. People soon began to try to get rid of the bears close to their houses
to keep it safe and clean. This also plays a part in habitat destruction. All the
houses and infrastructure created in rural area where the bears liked to live
created fewer spots for the bears to habitat. This is the largest reason the
Grizzly Bear’s habitat changed so much throughout history and eventually
affected their population.
Continuing Threats
Grizzly Bears still are affected
by the same human conflicts that originally got them on the “Threatened Species”
list. However, the largest threat to the Grizzly Bear population today is
climate change. With the temperatures around the world getting warmer, they are
forced into smaller territories. Furthermore, much of their food supply is also
being affected by climate change. Things such as White Bark Pines and fresh
water Salmon are some of the Grizzly Bears most vital source of food. The
warming temperatures are directly affecting these species and will cause a
shortage in the food supply for bears.
Recovery Plan
What Can You Do?
Some of the simplest things can
help the Grizzly Bear population tremendously. Besides being aware of your
ecological footprint to help with climate change, the best thing you can do to
help with threatened species, like the Grizzly Bear, is to spread the word. When
people encounter bears, contact your local Game Warden or Animal Control to
allow them to deal with the bears. You can even install such things as electric
fences so the bears stay away from your house. However, the best thing you can
do for all endangered species, is spread awareness and be cognizant of your
ecological footprint to help with climate change.
Other Resources
Listed below are some website that can help you learn more
about Grizzly Bears and how you can help them!
National Parks
Service: www.nps.gov
U.S. Fish and
Wildlife Service: www.fws.gov
Defenders of
Wildlife: www.defenders.org
get BEAR SMART
society: www.bearsmart.com
Works
Cited
“Bear
Social Structure.” BioExpedition.
2017. Web. 2017.
Chagares,
Jim. “Grizzly Bear.” Defenders of
Wildlife. 2017. Web. 2017.
Keeler,
Leo. “Grizzly Bear.” Earth Justice. 2017.
Web. 2017.
“National
Parks Service.” United States Department
of the Interior. 2017. Website. 2017.
“North
America’s Bears.” get BEAR SMART society.
2017. Web. 2017.
Servheen,
Dr. Christopher. “Grizzly Bear Recovery Plan.” US Fish and Wildlife Service. Natural Science 312. University of
Montana. 2006. Print. 2017.
As the California State Animal, the Grizzly Bear is a species that are majestic and well-known, and I am saddened to see that the reasons behind its listing as threatened is primarily due to human conflict. It reminds me of the conflict that we saw in the ivory trade movie during class, where the native African population wanted to put down the elephant because it was going to encroach on their village and consume their crops. It is definitely a complicated issue, and really understand why the overall recovery plan for the Grizzly Bear costs $26,000,000.
ReplyDelete-Jay Gubbi
Very interesting! I did not know where their common name Grizzly came from, but it makes sense now. It is incredible that their historic range is so large, and they can live in many different habitats. I understand why people are scared of them, but it is sad that we have killed so many of them in a seemingly senseless manner.
ReplyDelete-Isabelle Farrell
Humans and Grizzlies have unfortunately never had a good relationship and I'm sad to see that this is one of the main reasons for their decline. Their public image has suffered immensely and, while human's fear of these animals is understandable, they are very misunderstood. They demand respect and are one of nature's most majestic predators.
ReplyDeleteGreat job!
-Cole Fukai
It's amazing that there has been such a massive decline in the grizzly bear population , less than 2% of those recorded in the 1800's. What I find interesting about the grizzly bears is that whenever I hear about them people are typically afraid of these creatures as being aggressive and attacking humans and yet, we are the main cause of their population decline, destroying their habitats. I agree that it is very important to simply inform people about how to effectively deal with these creatures because of how often humans encounter bears.
ReplyDelete-Samantha Friesen
I think it's interesting that Grizzly Bears are omnivores, as most animals at the top of the food chain are carnivores. I like how they live in Yellowstone because a lot of animals are very protected there. As figured, humans did most of the work to get these bears to be considered "threatened" by taking away their habitats. Hopefully their situation gets better. And nice blog!
ReplyDelete-Josh Gillespie
It is so sad that there are only 2% of grizzly bears now from reported numbers in the 1800s. I didn't know that climate change was directly effecting grizzly bears and their habitat, it is sad how many animals it is effecting. Great job on your blog, I really enjoyed reading about the grizzly bears.
ReplyDelete-Rebekah Fesmire
$26,000,000 to implement the recovery plan, that is crazy! I would hope that maybe they could limit that price to make it more affordable and easier for the species to be properly protected. It is so great to hear that they are no longer threatened in the Yellowstone area and that will give us hope that they are a species that can be saved. Great blog!
ReplyDelete-Katie Halstead