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Article by: Thomas M. Gehring Bradly A. Potter Presentation By: Ashley E. Wood

Wolf Habitat Analysis in Michigan: An Example of the Need for Proactive Land Management for Carnivore Species. Article by: Thomas M. Gehring Bradly A. Potter Presentation By: Ashley E. Wood. Background. Gray wolves are native to Michigan and once occurred in all 83 counties.

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Article by: Thomas M. Gehring Bradly A. Potter Presentation By: Ashley E. Wood

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  1. Wolf Habitat Analysis in Michigan: An Example of the Need for Proactive Land Management for Carnivore Species Article by: Thomas M. Gehring Bradly A. Potter Presentation By: Ashley E. Wood

  2. Background • Gray wolves are native to Michigan and once occurred in all 83 counties. • 1911: Locally extinct in the Lower Peninsula of Michigan. • 1960: Nearly extirpated from the Upper Peninsula. • 1965: Granted full legal protection by state Legislature. • 1973: Listed under the Endangered Species Act (ESA) with an estimated 6 wolves remaining. • 2012: Delisted from the ESA. References to the book: “A species is locally extinct when it is no longer found in an area it once inhabited but is still found elsewhere in the wild” (Primack 2010:134). “In the United States, the principal conservation law protecting species is the [ESA], passed in 1973” (Primack 2010:471).

  3. Background Wolf population increases in Michigan's Upper Peninsula. The population from 1989 to 2011. Credit MDNR

  4. Background References to the book: “Flagship and indicator species, whose protection automatically extends protection to other species and the community, are known as umbrella species” (Primack 2010:353). • Gray wolves can disperse great distances and can also cross long stretches of ice. • Only 6.5 km separate the Upper Peninsula from the Northern Lower Peninsula at the narrowest part of the Straits of Mackinac, providing a potential route of wolf dispersal. • Conserving large carnivore habitat in the NLP for wolves can be enable managers to conserve greater amounts of biodiversity. • Wolves may act as an umbrella species.

  5. Objectives • To determine the distribution and quantity of potential habitat available for gray wolves in the Northern Lower Peninsula. • To estimate the potential population size of gray wolves this available habitat could support. • To present and discuss management challenges and suggested strategies.

  6. Methods Reference to book: “Habitat fragmentation is the process whereby a large, continuous area of habitat is both reduced in area and divided into two or more fragments” (Primack 2010:189). • Step 1 – Acquired a Geographic Information System (GIS) map of road coverage for the NLP • Step 2 – Divided the GIS coverage into 1-km2 cells using an ArcMAP density tool and assigned each cell a road-density value • Step 3 – Averaged cells within a 10-km radius from the center of each focal cell by combining neighborhood statistics with a moving-window analysis • Step 4 – Mladenoff et al. (1995) Calculated the probability of wolf presence using averaged cell values as follows: logit(p) = -6.5988+ 14.6189R • P = probability of wolf presence • R = road density

  7. Methods • Step 5 – Fuller et al. (1992) and Mladenoff et al. (1997) Calculated the number of wolves using the predicted area of potential wolf habitat as follows: N = {AW / [M(l+i)]) / (I-D) • N = estimated number of wolves • A = area of favorable habitat • W = mean midwinter pack size (4.1) • i = proportion of saturated habitat in interstitial areas (0.37) • D = proportion of dispersers (0.15) • Definition of favorable habitat varied. • <50 km2 and >50 km2 vs. only >50 km2

  8. Results • Approximately 40,000 km2 with a 0.00 % probability of wolf presence • 14 patches of potential habitat >50 km2 (p>0.5) • At least 1 livestock farm on all 14 habitat patches Top: Distribution of potential habitat for gray wolves in the NLP. Right: Amount of potential habitat for gray wolves in probability classes 0-1.

  9. Results • 4,231 km2 of favorable wolf habitat (p>0.50) • 2,198 km2 of favorable wolf habitat excluding patches <50 km2 • Majority of favorable habitat to the northeast • 61% of favorable habitat publicly owned Top: Distribution of potential favorable habitat for gray wolves in the NLP. Left: Amount of potential habitat for gray wolves in probability classes 0-1.

  10. Results • An estimated 89 wolves for 4,231 km2 of favorable wolf habitat • 90% CI • 78 – 105 wolves • An estimated 46 wolves for 2,198 km2 of favorable wolf habitat • 90% CI • 40 – 54 wolves

  11. Discussion • A wolf population in the NLP would possibly provide a second wolf population in the northern Great Lakes Region • But, the amount of potential favorable wolf habitat is considerably less than Wisconsin and the UP. Consequences: • Smaller population size • Increased risk of extinction • Increased risk of hybridization References to the book: “Small populations are more likely to go locally extinct than large populations because of their greater vulnerability to loss of genetic variability” (Primack 2010:159). “When a species is rare or its habitat is damaged, outbreeding– mating between individuals of different populations or species – may occur” (Primack2010:255).

  12. Discussion Suggested Management Strategies • Increase state-level protection of gray wolves in NLP • Increase favorable habitat in NLP by decreasing road density • Road closures on public and private land • Change management scale for addressing wolf-livestock conflicts on agricultural lands • Current scale of management = individually affected farms • Proposed scale before recolonization = neighborhoods of farms • Proposed scale after recolonization = wolf pack territories

  13. Discussion • Removal of wolves from individually affected farms is a short-lived solution • Farms are not independent • Ex: A livestock carcass dump on one farm can increase wolf conflicts for farming neighborhood • Removal of whole wolf packs could create sink habitats. Results: • Declining wolf numbers • Local extinction

  14. Discussion Suggested Management Strategies • Increase social tolerance for wolves • Communicate and cooperate with stakeholders to increase their understanding and involvement in gray wolf conservation • Institute Carnivore Habitat Incentive Program (CHIP) to increase gray wolf conservation on private farm lands • Ex: Financial incentive for proactive, nonlethal control tools • Include incentives for nonfarm landowners • Ex: Financial incentive for reducing vehicular traffic on property

  15. Resources Gehring, T. M., and B. A. Potter. 2005. Wolf habitat analysis in Michigan: An example of the need for carnivore species. Wildlife Society Bulletin 33:1237-1244. Fuller, T. K., W. E. Berg, G. L. Radde, M. S. Lenarz, and G. B. Joselyn. 1992. A history and current estimate of wolf distribution and numbers in Minnesota. Wildlife Society Bulletin 20:42-55. Mladenoff, D. J., T. A. Sickley, R. G. Haight, and A. P. Wydeven. 1995. A regional landscape analysis and prediction of favorable gray wolf habitat in the northern Great Lakes Region. Conservation Biology 9:279-294. Mladenoff, D. J., R. G. Haight, T. A. Sickley and A. P. Wydeven. 1997. Causes and implications of species restoration in altered ecosystems: a spatial landscape projection of wolf population recovery. BioScience 47:21-31. Primack, R. B. 2010. Essentials of conservation biology. Sinauer Associates, Inc., Sunderland, Massachusetts, USA.

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