Monitoring gray wolf populations using multiple survey methods

David E. Ausband, Lindsey N. Rich, Elizabeth M. Glenn, Michael S. Mitchell, Pete Zager, David Andrew Miller, Lisette P. Waits, Bruce B. Ackerman, Curt M. MacK

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

The behavioral patterns and large territories of large carnivores make them challenging to monitor. Occupancy modeling provides a framework for monitoring population dynamics and distribution of territorial carnivores. We combined data from hunter surveys, howling and sign surveys conducted at predicted wolf rendezvous sites, and locations of radiocollared wolves to model occupancy and estimate the number of gray wolf (Canis lupus) packs and individuals in Idaho during 2009 and 2010. We explicitly accounted for potential misidentification of occupied cells (i.e., false positives) using an extension of the multi-state occupancy framework. We found agreement between model predictions and distribution and estimates of number of wolf packs and individual wolves reported by Idaho Department of Fish and Game and Nez Perce Tribe from intensive radiotelemetry-based monitoring. Estimates of individual wolves from occupancy models that excluded data from radiocollared wolves were within an average of 12.0% (SD = 6.0) of existing statewide minimum counts. Models using only hunter survey data generally estimated the lowest abundance, whereas models using all data generally provided the highest estimates of abundance, although only marginally higher. Precision across approaches ranged from 14% to 28% of mean estimates and models that used all data streams generally provided the most precise estimates. We demonstrated that an occupancy model based on different survey methods can yield estimates of the number and distribution of wolf packs and individual wolf abundance with reasonable measures of precision. Assumptions of the approach including that average territory size is known, average pack size is known, and territories do not overlap, must be evaluated periodically using independent field data to ensure occupancy estimates remain reliable. Use of multiple survey methods helps to ensure that occupancy estimates are robust to weaknesses or changes in any 1 survey method. Occupancy modeling may be useful for standardizing estimates across large landscapes, even if survey methods differ across regions, allowing for inferences about broad-scale population dynamics of wolves.

Original languageEnglish (US)
Pages (from-to)335-346
Number of pages12
JournalJournal of Wildlife Management
Volume78
Issue number2
DOIs
StatePublished - Jan 1 2014

Fingerprint

survey method
Canis lupus
wolves
monitoring
carnivore
methodology
population dynamics
carnivores
radiotelemetry
population distribution
tribal peoples
modeling
radio telemetry
fish
prediction

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Nature and Landscape Conservation

Cite this

Ausband, D. E., Rich, L. N., Glenn, E. M., Mitchell, M. S., Zager, P., Miller, D. A., ... MacK, C. M. (2014). Monitoring gray wolf populations using multiple survey methods. Journal of Wildlife Management, 78(2), 335-346. https://doi.org/10.1002/jwmg.654
Ausband, David E. ; Rich, Lindsey N. ; Glenn, Elizabeth M. ; Mitchell, Michael S. ; Zager, Pete ; Miller, David Andrew ; Waits, Lisette P. ; Ackerman, Bruce B. ; MacK, Curt M. / Monitoring gray wolf populations using multiple survey methods. In: Journal of Wildlife Management. 2014 ; Vol. 78, No. 2. pp. 335-346.
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Ausband, DE, Rich, LN, Glenn, EM, Mitchell, MS, Zager, P, Miller, DA, Waits, LP, Ackerman, BB & MacK, CM 2014, 'Monitoring gray wolf populations using multiple survey methods', Journal of Wildlife Management, vol. 78, no. 2, pp. 335-346. https://doi.org/10.1002/jwmg.654

Monitoring gray wolf populations using multiple survey methods. / Ausband, David E.; Rich, Lindsey N.; Glenn, Elizabeth M.; Mitchell, Michael S.; Zager, Pete; Miller, David Andrew; Waits, Lisette P.; Ackerman, Bruce B.; MacK, Curt M.

In: Journal of Wildlife Management, Vol. 78, No. 2, 01.01.2014, p. 335-346.

Research output: Contribution to journalArticle

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