Can non-invasive methods replace radiocollar-based winter counts in a 50-year wolf study? Lessons learned from a three-winter trial
Shannon Michelle Barber-Meyer
A B *
+ Author Affiliations
- Author Affiliations
A Formerly US Geological Survey, Northern Prairie Wildlife Research Center, 8711 – 37th Street, SE, Jamestown, ND 58401-7317, USA.
B Present address: Pacific Whale Foundation, 300 Ma’alaea Road, Suite 211, Wailuku, HI 96793, USA.
Wildlife Research - https://doi.org/10.1071/WR22001
Submitted: 9 January 2022 Accepted: 21 June 2022 Published online: 16 August 2022
© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing
Abstract
Context: Monitoring low-density, elusive predators such as grey wolves (Canis lupus) has often been undertaken via live-capture and radio-collaring. Recent advances in non-invasive methods suggest live-captures may not be necessary for adequate monitoring. Further, non-invasive methods are considered best practice when possible.
Aims: I evaluated whether a suite of non-invasive methods could replace aerial radiotelemetry to census resident pack wolves.
Methods: I employed aerial snow-tracking, ground snow-tracking, camera-trapping, non-invasive genetic surveys, and community-scientist reports during three winters (2019–2021) in north-eastern Minnesota, USA to census pack wolves in a 2060 km2 area. I attempted to enumerate individual pack sizes as has been historically undertaken to compile the census. Traditional aerial radiotelemetry methods were also conducted for comparison.
Key results: Ground snow-tracking and camera-trapping provided the most similar information to radiotelemetry for determining pack counts and territory information, and, in some cases, documented higher pack counts than those obtained by aerial radiotelemetry. Radiotelemetry was the best method for determining pack territories, but was limited to radioed packs. A staggered application of both approaches resulted in increased precision and additional pack-level information without greatly increasing overall field effort. Non-invasive methods allowed trapping for radio-collaring to be reduced to every other year (a 50% reduction), but depending on trapping success, survival of animals, and radio-collar battery life, might even be reduced to every third year.
Conclusions: In this 3-year trial, non-invasive methods were not sufficient to completely replace radio-collaring. Nevertheless, non-invasive methods allowed for a 50% reduction in trapping, increased the annual wolf-count precision, and increased community involvement. Anticipated technological improvements in non-invasive methods should reduce some issues encountered – but others will likely persist, in part, because of the fundamental nature of non-invasive methods.
Implications: Less reliance on captures, enhanced pack information, and increased public involvement are all successful outcomes of this 3-year trial of non-invasive methods for monitoring wolf populations. Non-invasive methods continue to broaden and improve technologically, and information from trials such as this will help guide others as they increasingly implement non-invasive methods as partial or complete replacements for traditional capture-based methods.
Keywords: camera-trapping, Canis lupus, capture, census, community scientist, count, genetics, non-invasive, scat, snow-tracking, telemetry, trapping.
References
Åkesson, M, Svensson, L, Flagstad, Ø, Wabakken, P, and Frank, J (2022). Wolf monitoring in Scandinavia: evaluating counts of packs and reproduction events. Journal of Wildlife Management 86, e22206.Ausband, DE, Young, J, Fannin, B, Mitchell, MS, Stenglein, JL, Waits, LP, and Shivik, JA (2011). Hair of the dog: obtaining samples from coyotes and wolves noninvasively. Wildlife Society Bulletin 35, 105–111.
| Hair of the dog: obtaining samples from coyotes and wolves noninvasively.Crossref | GoogleScholarGoogle Scholar |
Balčiauskas, L, Balčiauskienė, L, Litvaitis, JA, and Tijušas, E (2020). Adaptive monitoring: using citizen scientists to track wolf populations when winter-track counts become unreliable. Wildlife Research 48, 76–85.
| Adaptive monitoring: using citizen scientists to track wolf populations when winter-track counts become unreliable.Crossref | GoogleScholarGoogle Scholar |
Barber-Meyer SM (2022) Wolf noninvasive methods trial from 2019–2021 in the Superior National Forest metadata. US Geological Survey Data Release.
| Crossref |
Barber-Meyer, SM, and Mech, LD (2014). How hot is too hot? Live-trapped gray wolf rectal temperatures and 1-year survival. Wildlife Society Bulletin 38, 767–772.
| How hot is too hot? Live-trapped gray wolf rectal temperatures and 1-year survival.Crossref | GoogleScholarGoogle Scholar |
Barber-Meyer, SM, and Mech, LD (2016). White-tailed Deer (Odocoileus virginianus) subsidize Gray Wolves (Canis lupus) during a Moose (Alces americanus) decline: a case of apparent competition? Canadian Field Naturalist 130, 308–314.
| White-tailed Deer (Odocoileus virginianus) subsidize Gray Wolves (Canis lupus) during a Moose (Alces americanus) decline: a case of apparent competition?Crossref | GoogleScholarGoogle Scholar |
Barber-Meyer, SM, Ryan, D, Grosshuesch, D, Catton, T, and Malick-Wahls, S (2018). Use of non-invasive genetics to generate core-area population estimates of a threatened predator in the Superior National Forest, USA. Canadian Wildlife Biology and Management 7, 46–55.
Barber-Meyer, SM, Dysthe, JC, and Pilgrim, KL (2020a). Testing environmental DNA from wolf snow tracks for species, sex, and individual identification. Canadian Wildlife Biology and Management 9, 12–20.
Barber-Meyer, SM, Palacios, V, Marti Domken, B, and Schmidt, LJ (2020b). Testing a new passive acoustic recording device to monitor wolves. Wildlife Society Bulletin 44, 590–598.
| Testing a new passive acoustic recording device to monitor wolves.Crossref | GoogleScholarGoogle Scholar |
Barber-Meyer SM, Mech LD, Wheeldon TJ (2021a) ‘Wolf survival and cause-specific mortality from 1968–2018 in the Superior National Forest data.’ US Geological Survey Data Release. (US Geological Survey) https://doi.org/
| Crossref |
Barber-Meyer, SM, Wheeldon, TJ, and Mech, LD (2021b). The importance of wilderness on wolf (Canis lupus) survival and cause of death over 50 years. Biological Conservation 258, 109145.
| The importance of wilderness on wolf (Canis lupus) survival and cause of death over 50 years.Crossref | GoogleScholarGoogle Scholar |
Barber-Meyer, SM, Zeller, V, and Pilgrim, KL (2022). Testing environmental DNA from wolf snow tracks for species, sex, and individual identification: an addendum. Canadian Wildlife Biology and Management 11, 14–16.
Brøseth, H, Flagstad, Ø, Wärdig, C, Johansson, M, and Ellegren, H (2010). Large-scale noninvasive genetic monitoring of wolverines using scats reveals density dependent adult survival. Biological Conservation 143, 113–120.
| Large-scale noninvasive genetic monitoring of wolverines using scats reveals density dependent adult survival.Crossref | GoogleScholarGoogle Scholar |
Frame, PF, and Meier, TJ (2007). Field-assessed injury to wolves captured in rubber-padded traps. Journal of Wildlife Management 71, 2074–2076.
| Field-assessed injury to wolves captured in rubber-padded traps.Crossref | GoogleScholarGoogle Scholar |
Frenzel, LD (1974). Occurrence of moose in food of wolves as revealed by scat analyses: a review of North American studies. Naturaliste Canadiene 101, 467–479.
Galaverni, M, Palumbo, D, Fabbri, E, Caniglia, R, Greco, C, and Randi, E (2012). Monitoring wolves (Canis lupus) by non-invasive genetics and camera trapping: a small-scale pilot study. European Journal of Wildlife Research 58, 47–58.
| Monitoring wolves (Canis lupus) by non-invasive genetics and camera trapping: a small-scale pilot study.Crossref | GoogleScholarGoogle Scholar |
Gese, EM, Terletzky, PA, Erb, JD, Fuller, KC, Grabarkewitz, JP, Hart, JP, Humpal, C, Sampson, BA, and Young, JK (2019). Injury scores and spatial responses of wolves following capture: cable restraints versus foothold traps. Wildlife Society Bulletin 43, 42–52.
| Injury scores and spatial responses of wolves following capture: cable restraints versus foothold traps.Crossref | GoogleScholarGoogle Scholar |
Harrington, FH, and Mech, LD (1982). An analysis of howling response parameters useful for wolf pack censusing. Journal of Wildlife Management 46, 686–693.
| An analysis of howling response parameters useful for wolf pack censusing.Crossref | GoogleScholarGoogle Scholar |
Hedrick, PW, Stahler, DR, and Dekker, D (2014). Heterozygote advantage in a finite population: black color in wolves. Journal of Heredity 105, 457–465.
| Heterozygote advantage in a finite population: black color in wolves.Crossref | GoogleScholarGoogle Scholar |
Hedrick, PW, Smith, DW, and Stahler, DR (2016). Negative-assortative mating for color in wolves. Evolution 70, 757–766.
| Negative-assortative mating for color in wolves.Crossref | GoogleScholarGoogle Scholar |
Heinselman ML (1996) ‘The boundary waters wilderness ecosystem.’ (University of Minnesota Press: Minneapolis, MN, USA)
Hellström M, Wijkmark N, Edbom-Blomstrand C, Hellström P, Näslund J (2019) Footsteps in the snow—Pilot study for future monitoring of individual lynx (Lynx lynx) from eDNA in snow tracks. AquaBiota Report 2019, p. 10. (AquaBiota) Available at https://www.aquabiota.se/en/reports/
Iannarilli F, Erb J, Arnold T, Fieberg J (2016) Evaluation of design and analysis of a camera-based multi-species occupancy survey of carnivores in Minnesota. Summaries of Wildlife Research Findings, 187–204. Available at https://files.dnr.state.mn.us/wildlife/research/summaries/2017/fur/2017fur002.pdf
Kojola, I, Helle, P, Heikkinen, S, Lindén, H, Paasivaara, A, and Wikman, M (2014). Tracks in snow and population size estimation: the wolf Canis lupus in Finland. Wildlife Biology 20, 279–284.
| Tracks in snow and population size estimation: the wolf Canis lupus in Finland.Crossref | GoogleScholarGoogle Scholar |
Kuehn, DW, Fuller, TK, Mech, LD, Paul, WJ, Fritts, SH, and Berg, WE (1986). Trap related injuries to wolves in Minnesota. Journal of Wildlife Management 50, 90–91.
| Trap related injuries to wolves in Minnesota.Crossref | GoogleScholarGoogle Scholar |
Learn, JR (2021). Pulling DNA out of the air. , .
Long RA, MacKay P, Ray J, Zielinski W (Eds) (2012) ‘Noninvasive survey methods for carnivores.’ (Island Press: Washington, DC, USA)
Loonam, KE, Ausband, DE, Lukas, PM, Mitchell, MS, and Robinson, HS (2021). Estimating abundance of an unmarked, low-density species using cameras. Journal of Wildlife Management 85, 87–96.
| Estimating abundance of an unmarked, low-density species using cameras.Crossref | GoogleScholarGoogle Scholar |
Lucchini, V, Fabbri, E, Marucco, F, Ricci, S, Boitani, L, and Randi, E (2002). Noninvasive molecular tracking of colonizing wolf (Canis lupus) packs in the western Italian Alps. Molecular Ecology 11, 857–868.
| Noninvasive molecular tracking of colonizing wolf (Canis lupus) packs in the western Italian Alps.Crossref | GoogleScholarGoogle Scholar |
Marucco, F, Vucetich, LM, Peterson, RO, Adams, JR, and Vucetich, JA (2012). Evaluating the efficacy of non-invasive genetic methods and estimating wolf survival during a ten-year period. Conservation Genetics 13, 1611–1622.
| Evaluating the efficacy of non-invasive genetic methods and estimating wolf survival during a ten-year period.Crossref | GoogleScholarGoogle Scholar |
Mech LD (1973) ‘Wolf numbers in the Superior National Forest of Minnesota.’ USDA Forest Service Research Paper NC-97. (North Central Forest Experimental Station: St Paul, Minnesota, USA)
Mech LD (1974) Current techniques in the study of elusive wilderness carnivores. In ‘Proceedings of the 11th International Congress of Game Biologists’, 3–7 September 1973, Stockholm. pp. 315–322. (National Swedish Environment Protection Board: Stockholm, Sweden)
Mech LD (1986) ‘Wolf numbers and population trend in the Superior National Forest, 1967–1985.’ USDA Forest Service Research Paper NC-270. (North Central Forest Experimental Station: St Paul, Minnesota, USA)
Mech LD (2009) Long-term research on wolves in the Superior National Forest. In ‘Recovery of Gray Wolf in the Great Lakes Region of the United States: an endangered species success story’. (Eds AP Wydeven, TR VanDeelen, EJ Heske) pp. 15–34. (Springer: New York, NY, USA)
Mech LD, Barber S (2002) A critique of wildlife radio-tracking and its uses in National Parks. US National Park Service Report. (United States National Park Service: Fort Collins, CO).
Mech, LD, and Barber-Meyer, SM (2020). Sixty years of white-tailed deer (Odocoileus virginianus) yarding in a wolf (Canis lupus) and deer system. The Canadian Field-Naturalist 133, 343–351.
| Sixty years of white-tailed deer (Odocoileus virginianus) yarding in a wolf (Canis lupus) and deer system.Crossref | GoogleScholarGoogle Scholar |
Mech LD, Frenzel LD Jr (Eds) (1971) ‘Ecological studies of the timber wolf in northeastern Minnesota.’ USDA Forest Service Research Paper NC-52. (North Central Forest Experimental Station: St Paul, MN, USA)
Mech, LD, Seal, US, and DelGiudice, GD (1987). Use of urine in snow to indicate condition of wolves. Journal of Wildlife Management 51, 10–13.
| Use of urine in snow to indicate condition of wolves.Crossref | GoogleScholarGoogle Scholar |
Mech LD, Adams LG, Meier TJ, Burch JW, Dale BW (1998) ‘The wolves of Denali.’ (University of Minnesota Press: Minneapolis, MN, USA)
Mech, LD, Fieberg, J, and Barber-Meyer, S (2018). An historical overview and update of wolf–moose interactions in northeastern Minnesota. Wildlife Society Bulletin 42, 40–47.
| An historical overview and update of wolf–moose interactions in northeastern Minnesota.Crossref | GoogleScholarGoogle Scholar |
Miller, CR, Joyce, P, and Waits, LP (2005). A new method for estimating the size of small populations from genetic mark–recapture data. Molecular Ecology 14, 1991–2005.
| A new method for estimating the size of small populations from genetic mark–recapture data.Crossref | GoogleScholarGoogle Scholar |
Nelson, ME, and Mech, LD (1981). Deer social organization and wolf depredation in northeastern Minnesota. Wildlife Monographs 77, 3–53.
Nelson ME, Mech LD (1986a) ‘Deer population in the Central Superior National Forest, 1967–1985, Research Paper NC-271.’ (US Department of Agriculture, Forest Service, North Central Forest Experiment Station: St Paul, MN, USA). https://doi.org/
| Crossref |
Nelson, ME, and Mech, LD (1986b). Mortality of white-tailed deer in northeastern Minnesota. Journal of Wildlife Management 50, 691–698.
| Mortality of white-tailed deer in northeastern Minnesota.Crossref | GoogleScholarGoogle Scholar |
O’Brien, DJ, Beyer, DE, Largent, E, Melotti, JR, Ott-Conn, CN, Lonsway, DH, Cooley, TM, Atkinson, R, Clayson, M, and Straka, KA (2022). Foot injuries in Michigan, USA, gray wolves (Canis lupus), 1992–2014. Journal of Wildlife Diseases 58, 148–157.
Olson, SF (1938). Organization and range of the pack. Ecology 19, 168–170.
| Organization and range of the pack.Crossref | GoogleScholarGoogle Scholar |
Patterson, BR, Quinn, NWS, Becker, EF, and Meier, DB (2004). Estimating wolf densities in forested areas using network sampling of tracks in snow. Wildlife Society Bulletin 32, 938–947.
| Estimating wolf densities in forested areas using network sampling of tracks in snow.Crossref | GoogleScholarGoogle Scholar |
Pennell, MW, Stansbury, CR, Waits, LP, and Miller, CR (2013). Capwire: a R package for estimating population census size from non-invasive genetic sampling. Molecular Ecology Resources 13, 154–157.
| Capwire: a R package for estimating population census size from non-invasive genetic sampling.Crossref | GoogleScholarGoogle Scholar |
Peters, R, and Mech, LD (1975). Scent-marking in wolves: a field study. American Scientist 63, 628–637.
Rothman, RJ, and Mech, LD (1979). Scent-marking in lone wolves in and newly formed pairs. Animal Behaviour 27, 750–760.
| Scent-marking in lone wolves in and newly formed pairs.Crossref | GoogleScholarGoogle Scholar |
Rowcliffe, JM, Field, J, Turvey, ST, and Carbone, C (2008). Estimating animal density using camera traps without the need for individual recognition. Journal of Applied Ecology 45, 1228–1236.
| Estimating animal density using camera traps without the need for individual recognition.Crossref | GoogleScholarGoogle Scholar |
Sargeant, GA, Johnson, DH, and Berg, WE (1998). Interpreting carnivore scent-station surveys. Journal of Wildlife Management 62, 1235–1245.
| Interpreting carnivore scent-station surveys.Crossref | GoogleScholarGoogle Scholar |
Scandura, M (2005). Individual sexing and genotyping from blood spots on the snow: a reliable source of DNA for non-invasive genetic surveys. Conservation Genetics 6, 871–874.
| Individual sexing and genotyping from blood spots on the snow: a reliable source of DNA for non-invasive genetic surveys.Crossref | GoogleScholarGoogle Scholar |
Sikes, RS, the Animal Care and Use Committee of the American Society of Mammalogists (2016). 2016 Guidelines of the American Society of Mammalogists for the use of wild mammals in research and education. Journal of Mammalogy 97, 663–688.
| 2016 Guidelines of the American Society of Mammalogists for the use of wild mammals in research and education.Crossref | GoogleScholarGoogle Scholar |
Stansbury, CR, Ausband, DE, Zager, P, Mack, CM, Miller, CR, Pennell, MW, and Waits, LP (2014). A long-term population monitoring approach for a wide-ranging carnivore: noninvasive genetic sampling of gray wolf rendezvous sites in Idaho, USA. Journal of Wildlife Management 78, 1040–1049.
| A long-term population monitoring approach for a wide-ranging carnivore: noninvasive genetic sampling of gray wolf rendezvous sites in Idaho, USA.Crossref | GoogleScholarGoogle Scholar |
Stenglein, JL, Waits, LP, Ausband, DE, Zager, P, and Mack, CM (2010). Efficient, noninvasive genetic sampling for monitoring reintroduced wolves. Journal of Wildlife Management 74, 1050–1058.
| Efficient, noninvasive genetic sampling for monitoring reintroduced wolves.Crossref | GoogleScholarGoogle Scholar |
Stenglein, JL, Waits, LP, Ausband, DE, Zager, P, and Mack, CM (2011). Estimating gray wolf pack size and family relationships using noninvasive genetic sampling at rendezvous sites. Journal of Mammalogy 92, 784–795.
| Estimating gray wolf pack size and family relationships using noninvasive genetic sampling at rendezvous sites.Crossref | GoogleScholarGoogle Scholar |
Stępniak, KM, Niedźwiecka, N, Szewczyk, M, and Mysłajek, RW (2020). Scent marking in wolves Canis lupus inhabiting managed lowland forests in Poland. Mammal Research 65, 629–638.
| Scent marking in wolves Canis lupus inhabiting managed lowland forests in Poland.Crossref | GoogleScholarGoogle Scholar |
Turnbull, TT, Cain, JW, and Roemer, GW (2013). Anthropogenic impacts to the recovery of the Mexican gray wolf with a focus on trapping-related incidents. Wildlife Society Bulletin 37, 311–318.
| Anthropogenic impacts to the recovery of the Mexican gray wolf with a focus on trapping-related incidents.Crossref | GoogleScholarGoogle Scholar |
USDA Forest Service (2020) ‘Lynx analysis unit. Analysis for the Superior National Forest.’ (USDA Forest Service: Duluth, MN, USA)
Valiere, N, and Taberlet, P (2000). Urine collected in the field as a source of DNA for species and individual identification. Molecular Ecology 9, 2150–2152.
| Urine collected in the field as a source of DNA for species and individual identification.Crossref | GoogleScholarGoogle Scholar |
Waits, LP, and Paetkau, D (2005). Noninvasive genetic sampling tools for wildlife biologist: a review of applications and recommendations for accurate data collection. Journal of Wildlife Management 69, 1419–1433.
| Noninvasive genetic sampling tools for wildlife biologist: a review of applications and recommendations for accurate data collection.Crossref | GoogleScholarGoogle Scholar |
Weather Underground (2022) Ely, MN Weather History 2022. Available at https://www.wunderground.com/history/monthly/us/mn/ely/KELO [Accessed 6 June 2022]
Welbourne, DJ, MacGregor, C, Paull, D, and Lindenmayer, DB (2015). The effectiveness and cost of camera traps for surveying small reptiles and critical weight range mammals: a comparison with labour-intensive complementary methods. Wildlife Research 42, 414–425.
| The effectiveness and cost of camera traps for surveying small reptiles and critical weight range mammals: a comparison with labour-intensive complementary methods.Crossref | GoogleScholarGoogle Scholar |
Zemanova, MA (2020). Towards more compassionate wildlife research through the 3Rs principles: moving from invasive to non-invasive methods. Wildlife Biology 1, 17 March 2020, .
| Towards more compassionate wildlife research through the 3Rs principles: moving from invasive to non-invasive methods.Crossref | GoogleScholarGoogle Scholar |
