Mark-Recapture Survival Estimates of Sympatric Northern and Southern Flying Squirrels

Abstract

Climate change is shifting the ranges of many species, such as northern (Glaucomys sabrinus) and southern (Glaucomys volans) flying squirrels, and changing survival rates at range limits. Gaps in knowledge about vital rates exist for both species however, with no studies assessing sympatric populations. We undertook a study to address this gap, expecting higher survival for northern flying squirrels due to a slower life history. Using mark-recapture data from a long-term study of sympatric populations, we investigated survival rates and the effects of winter temperatures and mast seed abundance on these rates. Apparent annual survival was nearly equivalent during 2019–2023 (0.20 and 0.19 for northern and southern flying squirrels, respectively). We did not observe strong effects of acorn abundance or winter temperature on survival of either species. Our information will help with modeling to assess anticipated changes in the future as a result of ongoing climate warming.

Keywords

Cormack–Jolly–Seber / flying squirrels / mark-recapture / range expansion / survival estimates

References

[1] Arbogast, B. S., K. I. Schumacher, N. J. Kerhoulas, A. L. Bidlack, J. A. Cook, and G. J. Kenagy. 2017. “Genetic Data Reveal a Cryptic Species of New World Flying Squirrel: Glaucomys oregonensis.” Journal of Mammalogy 98, no. 4: 1027–1041. https://doi.org/10.1093/JMAMMAL/GYX055.

[2] Badia-Boher, J. A., J. Real, J. L. Riera, et al. 2023. “Joint Estimation of Survival and Dispersal Effectively Corrects the Permanent Emigration Bias in Mark‑Recapture Analyses.” Scientific Reports 13: 6970. https://doi.org/10.1038/s41598-023-32866-0.

[3] Blomberg, E. J., J. S. Sedinger, D. V. Nonne, and M. T. Atamian. 2013. “Seasonal Reproductive Costs Contribute to Reduced Survival of Female Greater Sage-Grouse.” Journal of Avian Biology 44, no. 2: 149–158. https://doi.org/10.1111/J.1600-048X.2012.00013.X.

[4] Bonner, S. J., and C. J. Schwarz. 2006. “An Extension of the Cormack–Jolly–Seber Model for Continuous Covariates With Application to Microtus pennsylvanicus.” Biometrics 62, no. 1: 142–149. https://doi.org/10.1111/J.1541-0420.2005.00399.X.

[5] Bowman, J., G. L. Holloway, J. R. Malcolm, K. R. Middel, and P. J. Wilson. 2005. “Northern Range Boundary Dynamics of Southern Flying Squirrels: Evidence of an Energetic Bottleneck.” Canadian Journal of Zoology 83, no. 11: 1486–1494. https://doi.org/10.1139/Z05-144.

[6] Brommer, J. E., R. Wistbacka, and V. Selonen. 2017. “Immigration Ensures Population Survival in the Siberian Flying Squirrel.” Ecology and Evolution 7: 1858–1868. https://doi.org/10.1002/ece3.2807.

[7] Cunningham, H. R., L. J. Rissler, L. B. Buckley, and M. C. Urban. 2016. “Abiotic and Biotic Constraints Across Reptile and Amphibian Ranges.” Ecography 39, no. 1: 1–8. https://doi.org/10.1111/ECOG.01369.

[8] Diggins, C. A. 2023. “Anthropogenically-Induced Range Expansion as an Invasion Front in Native Species: An Example in North American Flying Squirrels.” Frontiers in Ecology and Evolution 11: 1096244. https://doi.org/10.3389/fevo.2023.1096244.

[9] Dolan, P. G., and D. C. Carter. 1977. “Glaucomys volans.” Mammalian Species 78: 1–6.

[10] Duron, Q., T. Cornulier, E. Vidal, E. Bourguet, and L. Ruffino. 2020. “Combining Live and Lethal Trapping to Inform the Management of Alien Invasive Rodent Populations in a Tropical Montane Forest.” NeoBiota 63: 101–125. https://doi.org/10.3897/neobiota.63.53811.

[11] Endangered and Threatened Wildlife and Plants. 1982. “Review of Vertebrate Wildlife for Listing as Endangered or Threatened Species, 50 C.F.R pt.17.58459.” https://www.govinfo.gov/content/pkg/FR-1982-12-30/pdf/FR-1982-12-30.pdf#page=1.

[12] Ergon, T., and B. Gardner. 2014. “Separating Mortality and Emigration: Modelling Space Use, Dispersal and Survival With Robust-Design Spatial Capture–Recapture Data.” Methods in Ecology and Evolution 5, no. 12: 1327–1336. https://doi.org/10.1111/2041-210X.12133.

[13] Garroway, C. J., J. Bowman, T. J. Cascaden, et al. 2010. “Climate Change Induced Hybridization in Flying Squirrels.” Global Change Biology 16, no. 1: 113–121. https://doi.org/10.1111/J.1365-2486.2009.01948.X.

[14] Gomez, D. M., R. G. Anthony, and J. P. Hayes. 2005. “Influence of Thinning of Douglas-Fir Forests on Population Parameters and Diet of Northern Flying Squirrels.” Journal of Wildlife Management 69, no. 4: 1670–1682. https://doi.org/10.2193/0022-541X(2005)69[1670:IOTODF]2.0.CO;2.

[15] Gordon, S. P., D. N. Reznick, M. T. Kinnison, et al. 2009. “Adaptive Changes in Life History and Survival Following a New Guppy Introduction.” American Naturalist 174, no. 1: 34–45. https://doi.org/10.1086/599300.

[16] Hanski, I. K., and V. Selonen. 2009. “Female-Biased Natal Dispersal in the Siberian Flying Squirrel.” Behavioral Ecology 20, no. 1: 60–67. https://doi.org/10.1093/BEHECO/ARN115.

[17] Harlow, R. F., and A. T. Doyle. 1990. “Food Habits of Southern Flying Squirrels (Glaucomys volans) Collected From Red-Cockaded Woodpecker (Picoides borealis) Colonies in South Carolina.” American Midland Naturalist 124, no. 1: 187–191. https://doi.org/10.2307/2426093.

[18] Harsch, M. A., and J. HilleRisLambers. 2016. “Climate Warming and Seasonal Precipitation Change Interact to Limit Species Distribution Shifts Across Western North America.” PLoS One 11, no. 7: e0159184. https://doi.org/10.1371/JOURNAL.PONE.0159184.

[19] Helmick, K. R., T. L. Barrett, and G. W. Barrett. 2014. “Dietary Resource Preference of the Southern Flying Squirrel (Glaucomys volans).” American Midland Naturalist 171, no. 2: 371–374. https://doi.org/10.1674/0003-0031-171.2.371.

[20] Horton, G. E., B. H. Letcher, and W. L. Kendall. 2011. “A Multistate Capture–Recapture Modeling Strategy to Separate True Survival From Permanent Emigration for a Passive Integrated Transponder Tagged Population of Stream Fish.” Transactions of the American Fisheries Society 140, no. 2: 320–333. https://doi.org/10.1080/00028487.2011.567861.

[21] Jacques, C. N., J. S. Zweep, S. E. Jenkins, and R. W. Klaver. 2017. “Home Range Use and Survival of Southern Flying Squirrels in Fragmented Forest Landscapes.” Journal of Mammalogy 98, no. 5: 1479–1488. https://doi.org/10.1093/JMAMMAL/GYX089.

[22] Krichbaum, K., C. G. Mahan, M. A. Steele, G. Turner, and P. J. Hudson. 2010. “The Potential Role of Strongyloides robustus on Parasite-Mediated Competition Between Two Species of Flying Squirrels (Glaucomys).” Journal of Wildlife Diseases 46, no. 1: 229–235. https://doi.org/10.7589/0090-3558-46.1.229.

[23] Laake, J. L., D. S. Johnson, and P. B. Conn. 2013. “Marked: An R Package for Maximum Likelihood and Markov Chain Monte Carlo Analysis of Capture–Recapture Data.” Methods in Ecology and Evolution 4, no. 9: 885–890. https://doi.org/10.1111/2041-210X.12065.

[24] Lancaster, L. T., R. Y. Dudaniec, B. Hansson, and E. I. Svensson. 2015. “Latitudinal Shift in Thermal Niche Breadth Results From Thermal Release During a Climate-Mediated Range Expansion.” Journal of Biogeography 42, no. 10: 1953–1963. https://doi.org/10.1111/JBI.12553.

[25] Lehmkuhl, J. F., K. D. Kistler, J. S. Begley, and J. Boulanger. 2006. “Demography of Northern Flying Squirrels Informs Ecosystem Management of Western Interior Forests.” Ecological Applications 16, no. 2: 584–600. https://doi.org/10.1890/1051-0761(2006)016[0584:DONFSI]2.0.CO;2.

[26] MacArthur, R. H. 1984. Geographical Ecology: Patterns in the Distribution of Species. Princeton University Press.

[27] Maser, Z., C. Maser, and J. M. Trappe. 1985. “Food Habits of the Northern Flying Squirrel (Glaucomys sabrinus) in Oregon.” Canadian Journal of Zoology 63, no. 5: 1084–1088. https://doi.org/10.1139/z85-162.

[28] McCarthy, M. A., R. Citroen, and S. C. McCall. 2008. “Allometric Scaling and Bayesian Priors for Annual Survival of Birds and Mammals.” American Naturalist 172, no. 2: 216–222. https://doi.org/10.1086/588074.

[29] Molles, M. C., J. F. Cahill, and A. Laursen. 2017. Ecology Concepts and Applications ( 4th ed.). McGraw-Hill Ryerson Limited.

[30] Moritz, C., J. L. Patton, C. J. Conroy, J. L. Parra, G. C. White, and S. R. Beissinger. 2008. “Impact of a Century of Climate Change on Small-Mammal Communities in Yosemite National Park, USA.” Science 322: 261–264. https://doi.org/10.1126/science.1163428.

[31] Normand, S., U. A. Treier, C. Randin, P. Vittoz, A. Guisan, and J. C. Svenning. 2009. “Importance of Abiotic Stress as a Range-Limit Determinant for European Plants: Insights From Species Responses to Climatic Gradients.” Global Ecology and Biogeography 18, no. 4: 437–449. https://doi.org/10.1111/J.1466-8238.2009.00451.X.

[32] O'Brien, P. P., J. Bowman, S. L. Newar, and C. J. Garroway. 2022. “Testing the Parasite-Mediated Competition Hypothesis Between Sympatric Northern and Southern Flying Squirrels.” International Journal for Parasitology: Parasites and Wildlife 17: 83–90. https://doi.org/10.1016/j.ijppaw.2021.11.001.

[33] O'Brien, P. P., J. Bowman, A. B. Coombs, S. L. Newar, and C. J. Garroway. 2021. “Winter Nest Trees of Sympatric Northern (Glaucomys sabrinus) and Southern (Glaucomys volans) Flying Squirrels: A Test of Reinforcement in a Hybrid Zone.” Canadian Journal of Zoology 99, no. 10: 859–866. https://doi.org/10.1139/cjz-2021-0086.

[34] Patterson, J. E. H., and S. J. Patterson. 2010. “Multiple Annual Litters in Glaucomys sabrinus (Northern Flying Squirrel).” Northeastern Naturalist 17, no. 1: 167–169. https://doi.org/10.1656/045.017.0115.

[35] Perret, N., R. Pradel, C. Miaud, O. Grolet, and P. Joly. 2003. “Transience, Dispersal and Survival Rates in Newt Patchy Populations.” Journal of Animal Ecology 72, no. 4: 567–575. https://doi.org/10.1046/j.1365-2656.2003.00726.x.

[36] Persad, R., S. M. Stead, R. B. Stephens, and J. Bowman. 2025. “Home Range Size, Habitat Selection, and Mycophagy of Sympatric North American Flying Squirrels.” Ecosphere 16: e70333. https://doi.org/10.1002/ecs2.70333.

[37] Ponchon, A., R. Choquet, J. Tornos, K. D. McCoy, T. Tveraa, and T. Boulinier. 2018. “Survival Estimates Strongly Depend on Capture–Recapture Designs in a Disturbed Environment Inducing Dispersal.” Ecography 41, no. 12: 2055–2066. https://doi.org/10.1111/ECOG.03334.

[38] Price, P. W., M. Westoby, and B. Rice. 1988. “Parasite-Mediated Competition: Some Predictions and Tests.” American Naturalist 131, no. 4: 544–555. https://doi.org/10.1086/284805.

[39] Priol, P., M. J. Mazerolle, L. Imbeau, P. Drapeau, C. Trudeau, and J. Ramière. 2014. “Using Dynamic N-Mixture Models to Test Cavity Limitation on Northern Flying Squirrel Demographic Parameters Using Experimental Nest Box Supplementation.” Ecology and Evolution 4, no. 11: 2165–2177. https://doi.org/10.1002/ECE3.1086.

[40] Ransome, D. B., P. M. F. Lindgren, D. S. Sullivan, and T. P. Sullivan. 2004. “Long-Term Responses of Ecosystem Components to Stand Thinning in Young Lodgepole Pine Forest. I. Population Dynamics of Northern Flying Squirrels and Red Squirrels.” Forest Ecology and Management 202, no. 1/3: 355–367. https://doi.org/10.1016/J.FORECO.2004.08.002.

[41] Root, T. 1988. “Environmental Factors Associated With Avian Distributional Boundaries.” Journal of Biogeography 15, no. 3: 489–505. https://doi.org/10.2307/2845278.

[42] Rosentreter, R., G. D. Hayward, and M. Wicklow-Howard. 1997. “Northern Flying Squirrel Seasonal Food Habits in the Interior Conifer Forests of Central Ldaho, USA.” Northwest Science 71, no. 2: 97–102.

[43] Savage, V. M., J. F. Gillooly, J. H. Brown, G. B. West, and E. L. Charnov. 2004. “Effects of Body Size and Temperature on Population Growth.” American Naturalist 163, no. 3: 429–441. https://doi.org/10.1086/381872.

[44] Schaub, M., and J. A. Royle. 2014. “Estimating True Instead of Apparent Survival Using Spatial Cormack–Jolly–Seber Models.” Methods in Ecology and Evolution 5, no. 12: 1316–1326. https://doi.org/10.1111/2041-210X.12134.

[45] Selonen, V. 2004. “Young Flying Squirrels (Pteromys volans) Dispersing in Fragmented Forests.” Behavioral Ecology 15, no. 4: 564–571. https://doi.org/10.1093/BEHECO/ARH049.

[46] Selonen, V., and I. K. Hanski. 2006. “Habitat Exploration and Use in Dispersing Juvenile Flying Squirrels.” Journal of Animal Ecology 75, no. 6: 1440–1449. https://doi.org/10.1111/j.1365-2656.2006.01168.x.

[47] Selonen, V., and R. Wistbacka. 2016. “Siberian Flying Squirrels Do Not Anticipate Future Resource Abundance.” BMC Ecology 16: 51. https://doi.org/10.1186/s12898-016-0107-7.

[48] Smith, M. 2011. “Effects of Habitat Amount and Configuration on the Survival and Movement of the Northern Flying Squirrel (Glaucomys sabrinus) in a Forest Mosaic.” Doctoral thesis, University of New Brunswick. Libraries and Archives Canada.

[49] Sonenshine, D. E., D. M. Lauer, T. C. Walker, and B. L. Elisberg. 1979. “The Ecology of Glaucomys volans (Linnaeus, 1758) in Virginia.” Acta Theriologica 24, no. 26: 363–377. https://doi.org/10.4098/AT.arch.79-33.

[50] Stabb, M. A. 1988. COSEWIC Assessment and Status Report on the Southern Flying Squirrel (Glaucomys volans) in Canada. Committee on the Status of Endangered Wildlife in Canada.

[51] Taulman, J. F., and K. G. Smith. 2004. “Home Range and Habitat Selection of Southern Flying Squirrels in Fragmented Forests.” Mammalian Biology 69, no. 1: 11–27. https://doi.org/10.1078/1616-5047-113.

[52] Thomas, C. D. 2010. “Climate, Climate Change and Range Boundaries.” Diversity and Distributions 16, no. 3: 488–495. https://doi.org/10.1111/J.1472-4642.2010.00642.X.

[53] Weigl, P. D. 1968. “The Distribution of the Flying Squirrels, Glaucomys volans and G. sabrinus; An Evaluation of the Competitive Exclusion Idea.” PhD diss., Duke University.

[54] Weigl, P. D. 1977. “Status of the Northern Flying Squirrel, Glaucomys sabrinus coloratus, in North Carolina.” In Endangered and Threatened Plants and Animals of North Carolina, edited by J. E. Cooper, S. S. Robinson, and J. B. Funderburg, 398–400. North Carolina State Museum of Natural History.

[55] Weigl, P. D. 1978. “Resource Overlap, Interspecific Interactions and the Distribution of the Flying Squirrels, Glaucomys volans and G. sabrinus.” American Midland Naturalist 100, no. 1: 83–96. https://doi.org/10.2307/2424779.

[56] Wells-Gosling, N., and L. R. Heaney. 1984. “Glaucomys sabrinus.” Mammalian Species 229: 1–8.

[57] Wetzel, E. J., and P. D. Weigl. 1994. “Ecological Implications for Flying Squirrels (Glaucomys spp.) of Effects of Temperature on the In Vitro Development and Behavior of Strongyloides robustus.” American Midland Naturalist 131, no. 1: 43–54. https://doi.org/10.2307/2426607.

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