Science, education, and wolf conservation John A. Vucetich, Ph.D. School of Forest Resources & Environmental Science Michigan Technological University, Houghton, MI javuceti@mtu.edu 9/19/2018 Template copyright 2005 www.brainybetty.com

Template copyright 2005 www.brainybetty.com Isle Royale (544 km2) Thunder Bay, ON Lake Superior Sault Sainte Marie, MI Houghton, MI Duluth, MN 9/19/2018 Template copyright 2005 www.brainybetty.com

Template copyright 2005 www.brainybetty.com Wolves are recovering. Scientists have been studying wolves for some time. What insights can scientists offer efforts to recover and conserve? 9/19/2018 Template copyright 2005 www.brainybetty.com

Q1: How many deer do wolves kill in a year Q1: How many deer do wolves kill in a year? Q2: What kind of prey do wolves kill? Q3: How do wolves affect deer abundance?

How many prey do wolves kill? 1) Two ways to express the kill rate: # of kills per wolf per month. # of kills per pack per month. 2) Across North America ~160 estimates of kill rate 17 different places ~90 of these estimates come from Isle Royale. 3) Kill rate is almost always estimated during winter. 4) Know virtually nothing about kill rates from March through December.

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971, 1972 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971, 1972, 1973 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971-1974 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971-1975 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971-1981 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Jan. & Feb. of: 1971-1991 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Kill rates are EXTREMELY variable. Jan. & Feb. of: 1971-2000 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Kill rates are EXTREMELY variable. Maximum kill rate is 2-1/2 times typical kill rate. Minimum kill rate is 15% of typical kill rate. Jan. & Feb. of: 1971-2000 Kills per wolf per month minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical)

Kill rates: Isle Royale wolves & moose Kill rates are EXTREMELY variable. Maximum kill rate is 2-1/2 times typical kill rate. Minimum kill rate is 15% of typical kill rate. Jan. & Feb. of: 1971-2000 ¼ Kills per wolf per month When times are good (25% of the time), wolves get 2-4 times more food than when times are bad (25% of the time). minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical) ½ ¼

Kill rates: Isle Royale wolves & moose Kill rates are EXTREMELY variable, and only partly predictable. ¼ Kills per wolf per month wolves 0.17 unknown 0.54 minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical) ½ ¼

Isle Royale kill rates (Jan-Feb), 1971-2000 Kill rates are EXTREMELY variable, and only somewhat predictable. Isle Royale kill rates (Jan-Feb), 1971-2000 Kills / wolf / day minimum 0.13 (15% of typical) lower quartile 0.59 median 0.86 upper quartile 1.2 max 2.3 (2-1/2 times more than typical) R2=0.34

Kill Rates for Upper Michigan Wolves: group of ~30 wolves in packs of size 2-6 in U.P. Brett Huntzinger 2005

Between January and April, kill rate can vary five fold! Brett Huntzinger 2005

Kill Rates Kill rate varies from year to year. Kill rate varies from month to month. Kill rate varies with moose, wolves, snow, prey vulnerability Very little idea about summer kill rates. Kill rate studies tell us VERY little about the effect of wolves on prey abundance. We cannot answer the question: how many prey do wolves kill in a year?

Prey selection What kind of prey do wolves kill? If wolves primarily kill prey that are old, weak, or vulnerable to death from some other cause, perhaps: wolves will have little effect on prey abundance, wolves will cull genetically inferior prey, reduce rate of death due to starvation.

Prey selection By the 1970s, we knew (3 things): 1) Wolves test moose before killing them. They kill only 1 in 20 that they test. Wolves cannot kill 95% of the moose they encounter.

Prey selection By the 1970s, we knew: 2) About ½ of all the adult moose that wolves kill on Isle Royale have something seriously wrong with them (starving, jaw necrosis, arthritis).

Prey selection By the 1970s, we knew: 2) About ½ of all the moose that wolves kill on Isle Royale have something seriously wrong with them (starving, jaw necrosis, arthritis).

Prey selection By the 1970s, we knew: 2) About ½ of all the moose that wolves kill on Isle Royale have something seriously wrong with them (starving, jaw necrosis, arthritis).

Prey selection By the 1970s, we knew: 3) Wolves prefer to kill calves and old prey. Peterson 1977

Prey selection By the 1970s, we knew: 3) Wolves are usually only able to kill calves and old prey. Peterson 1977

Prey selection More recently… Ages of elk killed by hunters and wolves in Yellowstone. Greg Wright 2003

Prey selection More recently… Ages of deer killed by cars and wolves in Michigan. Huntzinger 2005

Prey selection What kind of prey do wolves kill? Wolves primarily kill prey that are young, old, weak, or vulnerable in some way. Perhaps: wolves affect prey abundance less than would be suggested by kill rate, wolves cull genetically inferior prey, reduce rate of death due to starvation.

Wolves & prey abundance How do wolves affect the abundance of prey populations?

Wolves & prey abundance – Isle Royale After the Isle Royale wolf population crashed in 1980 and remain low for a decade (due to disease), moose abundance increased dramatically. Moose Wolves Year 9/19/2018 Template copyright 2005 www.brainybetty.com

Wolves & prey abundance – Isle Royale Think about all the fluctuations in moose abundance. Can we explain those fluctuations? What causes those fluctuations? wolves, food, climate? Moose Wolves Year 9/19/2018 Template copyright 2005 www.brainybetty.com

Wolves & prey abundance – Isle Royale After watching for nearly 50 years, we still can’t explain a significant portion of fluctuations in Isle Royale moose. Of the influences we can identify, climate is most important, and wolves are least important. spring Thank you for your interest in the wolves and moose of Isle Royale. My discussion today consists of two portions: First, I’ll discuss the natural history of wolves and moose. Then in the second part of this talk, we’ll look at the research techniques and findings that are particular to Isle Royale.

Wolves & prey abundance – Yellowstone wolf reintroduction

Wolves & prey abundance – North America Prey abundance determines wolf abundance. 9/19/2018 Template copyright 2005 www.brainybetty.com

Wolves & prey abundance – North America Predators determine prey abundance. 40 studies: -- moose (26) -- caribou (7) -- elk (6) -- bison (1) N = 18 N = 17 N = 15 9/19/2018 Template copyright 2005 www.brainybetty.com