North American mammals face various threats to their environments and populations. Large predators like jaguars, gray wolves, and cougars faced historic declines due to hunting but some populations are now recovering through conservation efforts. However, they still face threats from habitat loss and human encroachment. Other species like bison, bighorn sheep, and sea lions experienced severe reductions from hunting and loss of habitat and food sources, but protected areas and laws have helped increase numbers for some. Conservation groups work to protect habitats and species while minimizing conflicts with human activities.

1. +
North
American
Mammals
Physical Environment
By: Amy Leonard and Kevan Wright

2. +
Climate
 North America embraces every climatic zone, from tropical rain
forest and savanna on the lowlands of Central America to areas
of permanent ice cap in central Greenland.
 Subarctic and tundra climates prevail in Northern Canada and
Northern Alaska
 Desert and semiarid conditions are found in interior regions cut
off by high mountains from rain-bearing westerly winds

3. +
Water
 Many Lakes and Rivers
 Great Lakes
 Mississippi River
 St. Johns River
 Atlantic Ocean and Pacific Ocean border the continent
 Swamps/Marshes/Everglades

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Temperature

5. +
Temperate in Southeast
Dry in the Midwest
Cold & Polar in the North

6. +
Threatened Organisms

7. +
Jaguar
 Endangered in Arizona,
California, Central and South
America, Louisiana, Mexico,
New Mexico, and Texas
 Populations have declined
mainly due to hunting for its
beautiful coat in the 1960s and
1970s
 Today, habitat loss is due
mainly to the clearing of forests
 Some poaching still occurs

8. +
Effect on other species
 Jaguars becoming extinct is effecting other species because
they are an indicator species.
 Jaguars need a lot of living space, and if an area of forest has
a healthy population of such animals, then we can be pretty
sure that the whole forest community is doing well.
 If Jaguars become extinct, we will lose our indicator as to how
well a forest ecosystem is doing.

9. +
What are we doing to help?
 We are working to protect northern jaguars in the core of their
range through on-the-ground and through the establishing a
Northern Jaguar Reserve.
 We are also building local support for conservation, minimizing
predator/livestock conflicts and implementing programs to
change the local community's perception of the jaguar from a
liability to an asset.

10. +
American Bison
 Endangered in Canada
 Can weigh over 1950 lbs
 Largest mammal in North
America
 Population was over
160,000, but was reduced to
less than 250 by 1900 due to:
 Hunting
 Diseases
 Populations have recovered
since the 1920s to a total
population of 9000 due to
conservation efforts by
Canadian conservationists

11. +
Effect on Environment
 Bison play a keystone role in grassland ecosystem health
 Grazing by bison increases native plant and wildlife diversity
 Nutrient cycling benefits plant growth and species distribution
 Bison wallows create a unique habitat
 Bison carcasses fertilize soil
 The loss of Bison would eliminate all these advantages and
negatively effect the environment they were once a part of

12. +
Gray Wolf
 Found in Mexico and the U.S.
 Largest of the canines
 7000 to 9000 wolves in Alaska
 More than 3500 in the lower 48 states
 Once was over 2 million
 Main threats:
 Hunting and trapping because it was
thought of as a nuisance
 Habitat loss due to human
encroachment into wolf territories
 The gray wolf population was almost
completely wiped out, but the gray wolf is
now legally protected

13. +
Gray Wolves Impact Elk
 Wolves are altering the abundance, distribution, group sizes,
movements and vigilance of elk. There are some indications
that these interactions may be causing new growth in willows
as elk are kept on the move by wolves and don’t stay to browse
in any one area very long
 Without wolves, elk would flourish in one particular area and
not be forced to migrate

14. +
Yellowstone National Park
Reintroduce Grey Wolves
 Yellowstone National Park and central Idaho reintroduced grey
wolves. “There will be no land use restrictions for wolves after
six packs are established. State and tribal wildlife agencies are
encouraged to lead wolf management outside national parks
and national wildlife refuges.”
 This reintroduction resulted in wolf population recovery in and
around Yellowstone National Park and in central Idaho by 2002.

15. +
Cougar
 Also known as Puma or Mountain
Lion
 Found in North, Central, and South
America
 Over 20 subspecies
 Can kill prey up to seven times their
body weight
 Has made a dramatic recovery with
over 30,000 in the US alone
 The main cause of decline is loss of
habitat
 Only 30 to 50 Florida panthers remain
in the wild today

16. +
Environmental Effects
 Cougar Predation Key To Ecosystem HealthScienceDaily
(Oct. 24, 2006) — “The general disappearance of cougars
from a portion of Zion National Park in the past 70 years
has allowed deer populations to dramatically
increase, leading to severe ecological damage, loss of
cottonwood trees, eroding streambanks, and declining
biodiversity.”

17. +
The Cougar Fund
 “The Cougar Fund was founded to help ensure the
conservation and protection of cougars throughout their range
in the United States and the rest of the Western Hemisphere.
Scientific research has shown us that healthy cougar
populations help to conserve healthy landscapes and the
biodiversity that enrich and sustain human life...Conserving
healthy and well-connected cougar populations not only helps
us fulfill our moral obligation to protect nature but also yields
immeasurable benefits to humans.”

18. +
Bighorn Sheep
 Found in British Columbia,
Washington, Oregon, Idaho,
California, Nevada, Utah, and
North Dakota
 There are an estimated 10,500
bighorn sheep left in the wild in
California
 Primary threats:
 unregulated or illegal hunting
 predation by mountain lions
and coyotes
 disease

19. +
Mexican Brown Bear
 Once found in Mexico and
southern United States
 Said to be possibly extinct
 The main cause of decline is a
dramatic reduction of habitat
due to human settlement
 Hunted for sport and in some
areas are killed because they
are believed to be dangerous to
humans and a threat to
livestock

20. +
Giant Kangaroo Rat
 Found in California
 1/20 species of kangaroo rats
 Is only found in one area of less
than five square miles between
the Carrizo Plain and the city of
Taft, in west-central California
 It is legally protected
 Threatened by habitat loss to
agricultural development

21. +
Mantled Howler Monkey
 Endangered from Mexico to
South America
 Threatened by habitat
destruction, rainforest
fragmentation and natural
disasters
 It is legally protected, and about
1300 individuals can be found
in protected areas

22. +
Steller Sea Lion
 Endangered in
Alaska, California, Canada, North
Pacific Ocean, Oregon, and
Washington
 Numbers have declined because
of :
 Accidental capture in fishnets
 Loss of food source to
fishermen, and hunting
 Some are shot each year by
fishermen who consider them
competition or pests to the
fishing industry
 This species is now legally
protected by the United
States, and intentional killing of
any Steller sea-lion is prohibited

23. +
Interview with Donna Leonard
 Click to hear interview


24. +
Graphs

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Citations
 http://nhb-
arcims.si.edu/mammals_arcims/viewer.htm?Title=North%20Am
erican%20Mammals
 http://www.earthsendangered.com/continent.asp?ID=9
 http://www.defenders.org/programs_and_policy/wildlife_conser
vation/imperiled_species/jaguar/
 http://www.cougarfund.org/conservation/conservation/