How Many Wolves are in Yellowstone?

Yellowstone Wolf Howl

Seeing a wolf in Yellowstone National Park is a rare and thrilling experience.

2015: 99 wolves running in 10 packs 

2014: 104 wolves running in 11 packs 

2013: 95 wolves in 10 packs 

Wolf Population Chart for Yellowstone National Park

Wolf Population Fluctuation

The wolf population in the Yellowstone region has constantly fluctuated in recent times largely due to food scarcity (especially fewer elk, their primary source of food), wolves killing other wolves, and human-related mortality both within the park and outside of it. As of December 2012, the population was down to 34 wolves, a significant decrease from December 2007 when the NPS recorded a total of 94 wolves living in the park. However, by 2015, that number had climbed to 99 wolves and 10 packs.

Many factors make predicting the Yellowstone wolf population difficult. Environmental conditions like severe winters, as well as human interactions like vehicle strikes and harvest outside the park, and pack immigration and emigration around park boundaries all significantly affect the final totals.

Wolf Harvesting

Each state where the wolves reside has its own management system for how and when wolves can be killed, although wolf harvesting is illegal within Yellowstone Park boundaries. Of course wolves don’t recognize park or state lines and often wander across them. This means a wolf that usually lives in Yellowstone, but crosses over into state land, can be harvested when it’s outside of the park.

In March 2013 the National Park Service recorded that 12 wolves had been legally killed outside Yellowstone’s boundaries. It’s estimated that the Yellowstone population could withstand even higher losses and still sustain itself.

Seven of the 10 wolf packs in the park lost at least one member during the 2012-13 hunting season. At least three were of high social status, either an alpha female or beta male, a fact potentially detrimental to reproduction, hunting behavior and territory defense in the short term, say National Park Service biologists. However, those biologists note that vacant spots in the wolves’ social hierarchy are quickly filled.

Reference http://www.nps.gov/yell/naturescience/wolfhunt.htm