Nearly Extinct Species: maybe only 100 individuals exist

Yellowstone NP 63 mi 54 mi 466 mi of roads 950 mi of backcountry trails 97 trailheads 287 backcountry campsites

http://www.youtube.com/watch?v=2aEULGJ05So&feature=fvw http://www.bing.com/videos/watch/video/crying-wolf-in-yellowstone/6198y2q (1:10) http://www.ksl.com/index.php?sid=3743475

Wolves in Yellowstone National Park

The last wolves in Yellowstone (1920’s)

Wolves commonly live in packs

Packs can kill larger prey Social vs Solo

Packs give the ability to obtain more food, but also mean sharing food, reduced chance of reproduction, and increased chance of diseases.

Wolves are very territorial and will kill intruders

Wolves were re-introduced to Yellowstone in 1995

Wolf relocation

“hard” release: directly to new location In Yellowstone used“soft” release: Kept in 1 acre pens to acclimate to new environment

Wolves were re-introduced to Yellowstone in 1995

Yellowstone area wolf packs 2004 http://www.forwolves.org/ralph/historical.html

Wolf deaths 1995-2005 38 deaths= 33%

The cost of wolves in Yellowstone NP: Currently about 300 wolves 2003- 137 sheep and 66 cattle = $32,000 2004- 209 sheep, 57 cattle, and 6 other animals = $70,000

Estimate millions of dollars in increased visitors

Predator-predator interactions

Predator-predator interactions

Yellowstone Grizzly Bear population increases

Wolves are decreasing the elk population

Benefits of decreasing herbivore populations

Increased Riparian Habitat

Increased Riparian Habitat Fig 2

Increased Riparian Habitat Fig 2

Increased Riparian Habitat Fig 3

Are wolves responsible? 1998 1999 2000 2001 year 1998 1999 2000 2001 Fig 5

high risk low risk

high risk low risk

high risk low risk

Are wolves responsible? 1998 1999 2000 2001 year 1998 1999 2000 2001 Fig 5

Protection vs herbivory gully depth vs browsing Fig 6

The greatest difference has been in the deepest gullies, which are at the greatest risk of erosion. Fig 6

The reintroduction of wolves to Yellowstone NP has had numerous positive benefits.

The reintroduction of wolves to Yellowstone NP has had numerous positive benefits: More food available for other carnivores

The reintroduction of wolves to Yellowstone NP has had numerous positive benefits: Increased Riparian Habitat Fig 3