Space invaders: effects of invasive alien Pallas’s squirrel on home range and body mass of native red squirrel

Abstract

Alien species can affect native species through several ecological processes such as competition. Here we tested the hypothesis of interspecific competition for space and food resources between the native Eurasian red squirrel and the invasive Pallas’s squirrel introduced in Italy. We used an experimental study design comparing space and habitat use and body condition parameters of red squirrels between areas of co-occurrence with the Pallas’s squirrel and areas without it. There were no differences in mean home range size of red squirrels between red-only areas and red-Pallas. However, when Pallas’s squirrels were removed, the red squirrels increased their home ranges. Moreover, in the area of syntopy, red squirrels had a higher degree of intraspecific home range overlap than in the red-only area. We also found indirect evidence for competition for food with red squirrels having a poorer body condition when co-occurring with the alien species. We analyzed the body mass and size of red squirrels in the two areas and our results showed that red squirrels had a reduced body mass and size when in syntopy, confirming that the interspecific competition does not allow red squirrels to reach the optimum body condition that they would have if the competitor was not present. Moreover, tree-species niche overlap was very high and both species fed primarily on the same tree seeds. Differences in vegetation cover between areas are discussed. This is the first study that confirms the invasiveness of the Pallas’s squirrel also in terms of capability to compete with native species.

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References

  1. Adriaens T, Baert K, Breyne P et al (2015) Successful eradication of a suburban Pallas’s squirrel Callosciurus erythraeus (Pallas 1779) (Rodentia, Sciuridae) population in Flanders (northern Belgium). Biol Invasions 17:2517–2526. doi:10.1007/s10530-015-0898-z

    Article  Google Scholar 

  2. Alexander JM, Edwards PJ (2010) Limits to the niche and range margins of alien species. Oikos 119:1377–1386. doi:10.1111/j.1600-0706.2009.17977.x

    Article  Google Scholar 

  3. Alterio N (1998) Spring home range, spatial organisation and activity of stoats Mustela erminea in a South Island Nothofagus forest, New Zealand. Ecography 21:18–24. doi:10.1111/j.1600-0587.1998.tb00390.x

    Article  Google Scholar 

  4. Andersson MB (1994) Sexual selection. Princeton University Press, Princeton

    Google Scholar 

  5. Bates D, Mächler M, Bolker B, Walker S (2014) Fitting linear mixed-effects models using lme4. arXiv preprint arXiv:1406.5823

  6. Bertolino S, Lurz PWW (2013) Callosciurus squirrels: worldwide introductions, ecological impacts and recommendations to prevent the establishment of new invasive populations. Mammal Rev 43:22–33. doi:10.1111/j.1365-2907.2011.00204.x

    Article  Google Scholar 

  7. Bertolino S, Cordero di Montezemolo N, Preatoni DG et al (2014) A grey future for Europe: sciurus carolinensis is replacing native red squirrels in Italy. Biol Invasions 16:53–62. doi:10.1007/s10530-013-0502-3

    Article  Google Scholar 

  8. Blackwell GL, Bassett SM, Dickman CR (2006) Measurement error associated with external measurements commonly used in small-mammal studies. J Mammal 87:216–223

    Article  Google Scholar 

  9. Bøhn T, Amundsen P-A (2001) The competitive edge of an invading specialist. Ecology 82:2150–2163. doi:10.2307/2680222

    Article  Google Scholar 

  10. Broennimann O, Treier UA, Müller-Schärer H et al (2007) Evidence of climatic niche shift during biological invasion. Ecol Lett 10:701–709. doi:10.1111/j.1461-0248.2007.01060.x

    CAS  Article  PubMed  Google Scholar 

  11. Bruemmer C, Lurz P, Larsen K, Gurnell J (1999) Impacts and management of the alien eastern gray squirrel in Great Britain and Italy: lessons for British Columbia. In: Proceedings of a conference on the biology and management of species and habitats at risk, Kamloops, BC, 15–19 February. Ministry of Environment, Lands and Parks, Victoria, BC, pp 341–349

  12. Cadi A, Joly P (2003) Competition for basking places between the endangered European pond turtle (Emys orbicularis galloitalica) and the introduced red-eared slider (Trachemys scripta elegans). Can J Zool 81:1392–1398. doi:10.1139/z03-108

    Article  Google Scholar 

  13. Caravaggi A, Montgomery WI, Reid N (2014) Range expansion and comparative habitat use of insular, congeneric lagomorphs: invasive European hares Lepus europaeus and endemic Irish hares Lepus timidus hibernicus. Biol Invasions 17:687–698. doi:10.1007/s10530-014-0759-1

    Article  Google Scholar 

  14. Cassini GH, Guichón ML (2009) Variaciones morfológicas y diagnosis de la ardilla de vientre rojo, Callosciurus erythraeus (Pallas, 1779), en Argentina. Mastozool Neotropical 16:39–47

    Google Scholar 

  15. Clavero M, García-Berthou E (2005) Invasive species are a leading cause of animal extinctions. Trends Ecol Evol 20:110. doi:10.1016/j.tree.2005.01.003

    Article  PubMed  Google Scholar 

  16. Edelman AJ, Koprowski JL (2005) Introduced Abert’s squirrels in the Pinaleño Mountains: a review of their natural history and potential impacts on the red squirrel. In: Sanderson HR, Koprowski JL (eds) Proceedings of the endangered Mount Graham red squirrel symposium. University of Arizona Press, Tucson

  17. Edelman AJ, Koprowski JL (2006) Seasonal changes in home ranges of Abert’s squirrels: impact of mating season. Can J Zool 84:404–411. doi:10.1139/z06-009

    Article  Google Scholar 

  18. Emmons LH (1980) Ecology and resource partitioning among nine species of African Rain Forest Squirrels. Ecol Monogr 50:31–54. doi:10.2307/2937245

    Article  Google Scholar 

  19. Scalera R, Genovesi P, Essl F, Rabitsch W (2012) The impacts of invasive alien species in Europe. European Environment Agency Technical Report 16:114

  20. Ferner JW (1974) Habitat relationships of Tamiasciurus hudsonicus and Sciurus aberti in the Rocky Mountains. Southwest Nat 18:470–473. doi:10.2307/3670306

    Article  Google Scholar 

  21. Goldstein EA, Butler F, Lawton C (2015) Frontier population dynamics of an invasive squirrel species: do introduced populations function differently than those in the native range? Biol Invasions 17:1181–1197. doi:10.1007/s10530-014-0787-x

    Article  Google Scholar 

  22. Gosler AG (1996) Environmental and social determinants of winter fat storage in the great tit parus major. J Anim Ecol 65:1–17. doi:10.2307/5695

    Article  Google Scholar 

  23. Guichón ML, Doncaster PC (2008) Invasion dynamics of an introduced squirrel in Argentina. Ecography 31:211–220. doi:10.1111/j.2007.0906-7590.05308.x

    Article  Google Scholar 

  24. Gurnell J (1987) Natural history of squirrels. Christopher Helm Publishers Ltd, London

    Google Scholar 

  25. Gurnell J, Lurz PWW, Wauters AL (2015) Years of interactions and conflict in Europe: competition between Eurasian red squirrels and North American grey squirrel. In: Shuttleworth CM, Lurz PWW, Hayward MW(eds) Red squirrels: ecology, conservation & management in Europe England, pp 19–37

  26. Harrington LA, Macdonald DW (2008) Spatial and temporal relationships between invasive American mink and native European polecats in the Southern United Kingdom. J Mammal 89:991–1000. doi:10.1644/07-MAMM-A-292.1

    Article  Google Scholar 

  27. Harrington LA, Harrington AL, Yamaguchi N et al (2009) The impact of native competitors on an alien invasive: temporal niche shifts to avoid interspecific aggression. Ecology 90:1207–1216. doi:10.1890/08-0302.1

    Article  PubMed  Google Scholar 

  28. Hofmannová L, Romeo C, Štohanzlová L et al (2016) Diversity and host specificity of coccidia (Apicomplexa: Eimeriidae) in native and introduced squirrel species. Eur J Protistol 56:1–14. doi:10.1016/j.ejop.2016.04.008

    Article  PubMed  Google Scholar 

  29. Hori M, Yamada M, Tsunoda N (2006) Line census and gnawing damage of introduced Formosan squirrels (Callosciurus erythraeus taiwanensis) in urban forests of Kamakura, Kanagawa, Japan. In: Assessment and control of biological invasion risks. Shoukadoh Book Sellers, Kyoto, Japan and IUCN, Gland, Switzerland, pp 204–209

  30. Houser JD, Ginsberg H, Jakob EM (2014) Competition between introduced and native spiders (Araneae: Linyphiidae). Biol Invasions 16:2479–2488. doi:10.1007/s10530-014-0679-0

    Article  Google Scholar 

  31. Humphries MM, Boutin S (1996) Reproductive demands and mass gains: a paradox in female red squirrels (Tamiasciurus hudsonicus). J Anim Ecol 65:332–338. doi:10.2307/5879

    Article  Google Scholar 

  32. Kenward RE, Holm JL (1993) On the replacement of the red squirrel in britain. a phytotoxic explanation. Proc R Soc Lond B Biol Sci 251:187–194. doi:10.1098/rspb.1993.0028

    CAS  Article  Google Scholar 

  33. Kobayashi R, Hasegawa M, Miyashita T (2006) Home range and habitat use of the exotic turtle Chelydra serpentina in the Inbanuma Basin, Chiba Prefecture, Central Japan. Curr Herpetol 25:47–55. doi:10.3105/1345-5834(2006)25[47:HRAHUO]2.0.CO;2

    Article  Google Scholar 

  34. Kuznetsova A, Brockhoff PB, Christensen RHB (2015) lmerTest: tests in linear mixed effects models. R package version 2.0–20

  35. Latini AO, Petrere M (2004) Reduction of a native fish fauna by alien species: an example from Brazilian freshwater tropical lakes. Fish Manag Ecol 11:71–79. doi:10.1046/j.1365-2400.2003.00372.x

    Article  Google Scholar 

  36. Lawton C, Rochford J (2007) The recovery of grey squirrel (Sciurus carolinensis) populations after intensive control programmes. Biol Environ Proc R Ir Acad 107:19–29. doi:10.3318/BIOE.2007.107.1.19

    Article  Google Scholar 

  37. Lomolino MV, Brown JH, Davis R (1989) Island biogeograhy of montane forest mammals in the American Southwest. Ecology 70:180–194. doi:10.2307/1938425

    Article  Google Scholar 

  38. Lurz PWW, Garson PJ, Wauters LA (2000) Effects of temporal and spatial variations in food supply on the space and habitat use of red squirrels (Sciurus vulgaris L.). J Zool 251:167–178. doi:10.1111/j.1469-7998.2000.tb00601.x

    Article  Google Scholar 

  39. Lurz PWW, Hayssen V, Geissler K, Bertolino S (2013) Callosciurus erythraeus (Rodentia: Sciuridae). Mamm Species 902:60–74. doi:10.1644/902.1

    Article  Google Scholar 

  40. Mayle BA, Broome AC (2013) Changes in the impact and control of an invasive alien: the grey squirrel (Sciurus carolinensis) in Great Britain, as determined from regional surveys. Pest Manag Sci 69:323–333. doi:10.1002/ps.3458

    CAS  Article  PubMed  Google Scholar 

  41. Mayle B, Ferryman M, Harry P (2007) Controlling grey squirrel damage to woodlands. Forestry Authority, Cambridge

    Google Scholar 

  42. Mazzamuto MV, Panzeri M, Wauters L et al (2015) Knowledge, management and optimization: the use of live traps in control of non-native squirrels. Mammalia 80:305–311. doi:10.1515/mammalia-2015-0006

    Google Scholar 

  43. Mazzamuto MV, Pisanu B, Romeo C et al (2016a) Poor parasite community of an invasive alien species: macroparasites of Pallas’s Squirrel in Italy. Ann Zool Fenn 53:103–112. doi:10.5735/086.053.0209

    Article  Google Scholar 

  44. Mazzamuto MV, Galimberti A, Cremonesi G et al (2016b) Preventing species invasion: a role for integrative taxonomy? Integr Zool 11:214–228. doi:10.1111/1749-4877.12185

    Article  PubMed  Google Scholar 

  45. Melero Y, Palazón S, Revilla E et al (2008) Space use and habitat preferences of the invasive American mink (Mustela vison) in a Mediterranean area. Eur J Wildl Res 54:609–617. doi:10.1007/s10344-008-0186-7

    Article  Google Scholar 

  46. Mazzamuto MV, Bisi F, Wauters LA et al (2017) Interspecific competition between alien Pallas’s squirrels and Eurasian red squirrels reduces density of the native species. Biol Invasions 19:723–735. doi:10.1007/s10530-016-1310-3

    Google Scholar 

  47. Miyamoto A, Tamura N, Sugimura K, Yamada F (2004) Predicting habitat distribution of the alien Formosan squirrel using logistic regression model. Glob Environ Res 8:13–22

    Google Scholar 

  48. Monteith KL, Stephenson TR, Bleich VC et al (2013) Risk-sensitive allocation in seasonal dynamics of fat and protein reserves in a long-lived mammal. J Anim Ecol 82:377–388. doi:10.1111/1365-2656.12016

    Article  PubMed  Google Scholar 

  49. Mooney HA, Cleland EE (2001) The evolutionary impact of invasive species. Proc Natl Acad Sci 98:5446–5451. doi:10.1073/pnas.091093398

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  50. Neuhaus P (2003) Parasite removal and its impact on litter size and body condition in Columbian ground squirrels (Spermophilus columbianus). Proc R Soc Lond B Biol Sci 270:S213–S215. doi:10.1098/rsbl.2003.0073

    Article  Google Scholar 

  51. Oftedal OT (2000) Use of maternal reserves as a lactation strategy in large mammals. Proc Nutr Soc 59:99–106. doi:10.1017/S0029665100000124

    CAS  Article  PubMed  Google Scholar 

  52. Palmer GH, Koprowski J, Pernas T (2007) Tree squirrels as invasive species: conservation and management implications. Managing Vertebrate Invasive Species, paper 36. http://digitalcommons.unl.edu/nwrcinvasive/36

  53. Parker JD, Torchin ME, Hufbauer RA et al (2013) Do invasive species perform better in their new ranges? Ecology 94:985–994

    Article  PubMed  Google Scholar 

  54. Pianka ER (1986) Ecology and natural history of desert lizards: analyses of the ecological niche and community structure. Princeton University Press, Princeton

    Google Scholar 

  55. Preatoni DG, Bisi F (2013) HRTools: commodity functions for home range calculation. https://r-forge.r-project.org/R/?group_id=1531

  56. R Development Core Team (2014) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna

    Google Scholar 

  57. Ricciardi A, Neves RJ, Rasmussen JB (1998) Impending extinctions of North American freshwater mussels (Unionoida) following the zebra mussel (Dreissena polymorpha) invasion. J Anim Ecol 67:613–619

    Article  Google Scholar 

  58. Romeo C, Wauters LA, Ferrari N et al (2014) Macroparasite fauna of alien grey squirrels (Sciurus carolinensis): composition, variability and implications for native species. PLoS ONE 9:e88002. doi:10.1371/journal.pone.0088002

    Article  PubMed  PubMed Central  Google Scholar 

  59. Ruiz-Miranda CR, Affonso AG, de Morais MM et al (2006) Behavioral and ecological interactions between reintroduced golden lion tamarins (Leontopithecus rosalia Linnaeus, 1766) and introduced marmosets (Callithrix spp, Linnaeus, 1758) in Brazil’s Atlantic Coast forest fragments. Braz Arch Biol Technol 49:99–109

    Article  Google Scholar 

  60. Schumacher BD, Parrish JD (2005) Spatial relationships between an introduced snapper and native goatfishes on hawaiian reefs. Biol Invasions 7:925–933. doi:10.1007/s10530-004-2983-6

    Article  Google Scholar 

  61. Shuttleworth CM, Lurz PWW, Hayward MW (2015) Red Squirrels: ecology, conservation & management in Europe. European Squirrel Initiative, Woodbridge

    Google Scholar 

  62. Sidorovich VE, Polozov AG, Zalewski A (2010) Food niche variation of European and American mink during the American mink invasion in north-eastern Belarus. Biol Invasions 12:2207–2217. doi:10.1007/s10530-009-9631-0

    Article  Google Scholar 

  63. Strubbe D, Matthysen E (2011) A radiotelemetry study of habitat use by the exotic Ring-necked Parakeet Psittacula krameri in Belgium. Ibis 153:180–184

    Article  Google Scholar 

  64. Stuyck J, Baert K, Breyne P, Adriaens T (2009) Invasion history and control of a Pallas squirrel Callosciurus erythraeus population in Dadizele, Belgium. In: Proceedings of the science facing aliens conference Brussels. Belgian Biodiversity Platform, Brussels, Belgium. p 46

  65. Tamura N, Nakane M, Satuo S, Hayashi F (1987) Home range size of the formosan squirrel Callosciurus eryhtareus thaiwanensis, estimated by radio tracking. J Mammal Soc Jpn 12:69–72

    Google Scholar 

  66. Tamura N, Hayashi F, Miyashita K (1988) Dominance hierarchy and mating behavior of the formosan squirrel, Callosciurus erythraeus thaiwanensis. J Mammal 69:320. doi:10.2307/1381382

    Article  Google Scholar 

  67. Tamura N, Hayashi F, Miyashita K (1989) Spacing and kinship in the Formosan squirrel living in different habitats. Oecologia 79:344–352

    CAS  Article  PubMed  Google Scholar 

  68. Teangana DÓ, Reilly S, Montgomery WI, Rochford J (2000) Distribution and status of the red squirrel (Sciurus vulgaris) and grey squirrel (Sciurus carolinensis) in Ireland. Mammal Rev 30:45–56. doi:10.1046/j.1365-2907.2000.00054.x

    Article  Google Scholar 

  69. Thorington RWJ, Koprowski JL, Steele MA, Whatton JF (2012) Squirrels of the world. Johns Hopkins University Press, Baltimore

    Google Scholar 

  70. Torchin ME, Lafferty KD, Kuris AM (2001) Release from parasites as natural enemies: increased performance of a globally introduced marine crab. Biol Invasions 3:333–345. doi:10.1023/A:1015855019360

    Article  Google Scholar 

  71. Tosi G, Zilio A (2002) Conoscenza delle risorse ambientali della provincia di Varese. Settore politiche per l’agricoltura e gestione faunistica, Provincia di Varese

    Google Scholar 

  72. van der Veen IT (1999) Effects of predation risk on diurnal mass dynamics and foraging routines of yellowhammers (Emberiza citrinella). Behav Ecol 10:545–551. doi:10.1093/beheco/10.5.545

    Article  Google Scholar 

  73. Warton DI, Hui FKC (2011) The arcsine is asinine: the analysis of proportions in ecology. Ecology 92:3–10. doi:10.1890/10-0340.1

    Article  PubMed  Google Scholar 

  74. Wauters L, Dhondt AA (1989) Body weight, longevity and reproductive success in red squirrels (Sciurus vulgaris). J Anim Ecol 58:637–651. doi:10.2307/4853

    Article  Google Scholar 

  75. Wauters L, Dhondt AA (1992) Spacing behaviour of red squirrels, Sciurus vulgaris: variation between habitats and the sexes. Anim Behav 43:297–311. doi:10.1016/S0003-3472(05)80225-8

    Article  Google Scholar 

  76. Wauters L, Dhondt AA (1993) Immigration pattern and success in red squirrels. Behav Ecol Sociobiol 33:159–167. doi:10.1007/BF00216596

    Article  Google Scholar 

  77. Wauters LA, Dhondt AA (1995) Lifetime reproductive success and its correlates in female Eurasian red squirrels. Oikos 72:402–410. doi:10.2307/3546126

    Article  Google Scholar 

  78. Wauters LA, Gurnell J (1999) The mechanism of replacement of red squirrels by grey squirrels: a test of the interference competition hypothesis. Ethology 105:1053–1071. doi:10.1046/j.1439-0310.1999.10512488.x

    Article  Google Scholar 

  79. Wauters LA, Lens L (1995) Effects of food availability and density on red squirrel (Sciurus vulgaris) reproduction. Ecology 76:2460–2469. doi:10.2307/2265820

    Article  Google Scholar 

  80. Wauters L, Dhondt AA, Vos RD (1990) Factors affecting male mating success in red squirrels (Sciurus vulgaris). Ethol Ecol Evol 2:195–204. doi:10.1080/08927014.1990.9525486

    Article  Google Scholar 

  81. Wauters LA, Lens L, Dhondt AA (1995) Variation in territory fidelity and territory shifts among red squirrel, Sciurus vulgaris, females. Anim Behav 49:187–193. doi:10.1016/0003-3472(95)80166-9

    Article  Google Scholar 

  82. Wauters LA, Dhondt AA, Knothe H, Parkin DT (1996) Fluctuating asymmetry and body size as indicators of stress in red squirrel populations in woodland fragments. J Appl Ecol 33:735. doi:10.2307/2404944

    Article  Google Scholar 

  83. Wauters LA, Lurz PWW, Gurnell J (2000) Interspecific effects of grey squirrels (Sciurus carolinensis) on the space use and population demography of red squirrels (Sciurus vulgaris) in conifer plantations. Ecol Res 15:271–284. doi:10.1046/j.1440-1703.2000.00354.x

    Article  Google Scholar 

  84. Wauters LA, Gurnell J, Martinoli A, Tosi G (2001a) Does interspecific competition with introduced grey squirrels affect foraging and food choice of Eurasian red squirrels? Anim Behav 61:1079–1091. doi:10.1006/anbe.2001.1703

    Article  Google Scholar 

  85. Wauters LA, Gurnell J, Preatoni D, Tosi G (2001b) Effects of spatial variation in food availability on spacing behaviour and demography of Eurasian red squirrels. Ecography 24:525–538. doi:10.1111/j.1600-0587.2001.tb00487.x

    Article  Google Scholar 

  86. Wauters L, Gurnell J, Martinoli A, Tosi G (2002a) Interspecific competition between native Eurasian red squirrels and alien grey squirrels: does resource partitioning occur? Behav Ecol Sociobiol 52:332–341. doi:10.1007/s00265-002-0516-9

    Article  Google Scholar 

  87. Wauters L, Tosi G, Gurnell J (2002b) Interspecific competition in tree squirrels: do introduced grey squirrels (Sciurus carolinensis) deplete tree seeds hoarded by red squirrels (S. vulgaris)? Behav Ecol Sociobiol 51:360–367. doi:10.1007/s00265-001-0446-y

    Article  Google Scholar 

  88. Wauters AL, Vermeulen M, Van Dongen S et al (2007a) Effects of spatio-temporal variation in food supply on red squirrel Sciurus vulgaris body size and body mass and its consequences for some fitness components. Ecography 30:51–65. doi:10.1111/j.2006.0906-7590.04646.x

    Article  Google Scholar 

  89. Wauters LA, Preatoni DG, Molinari A, Tosi G (2007b) Radio-tracking squirrels: performance of home range density and linkage estimators with small range and sample size. Ecol Model 202:333–344. doi:10.1016/j.ecolmodel.2006.11.001

    Article  Google Scholar 

  90. Wickham H (2009) ggplot2: elegant graphics for data analysis. Springer, New York

    Google Scholar 

  91. Wirsing AJ, Steury TD, Murray DL (2002) Relationship between body condition and vulnerability to predation in red squirrels and snowshoe hares. J Mammal 83:707–715. doi:10.1644/1545-1542(2002)083<0707:RBBCAV>2.0.CO;2

    Article  Google Scholar 

  92. Wittenberg R, Cock MJW (2001) Invasive alien species: a toolkit of best prevention and management practices. CABI, Wallingford

    Google Scholar 

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Acknowledgements

Authors thank Regione Lombardia, Provincia di Varese and all the students involved in the survey. A special thanks to Ambrogio Molinari, Dimitri Sonzogni, Giovanni Zardoni, Francesca Santicchia and Elisabetta Rossi. Thanks to Parco Pineta, Parco Adda Nord, Villa Castelbarco, Provincia di Bergamo. We thank Craig Shuttleworth and the anonymous reviewer for the careful reading of our manuscript and their many insightful comments and suggestions. We are also grateful to the European Squirrel Initiative (ESI) for funding radio-collars. This work was supported by the EU and realized under the LIFE09 NAT/IT/000095 EC-SQUARE Project. This is Paper No. 11 of the ECSQUARE project.

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Mazzamuto, M.V., Morandini, M., Panzeri, M. et al. Space invaders: effects of invasive alien Pallas’s squirrel on home range and body mass of native red squirrel. Biol Invasions 19, 1863–1877 (2017). https://doi.org/10.1007/s10530-017-1396-2

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Keywords

  • Callosciurus erythraeus
  • Sciurus vulgaris
  • Body condition
  • Radio tracking
  • Removal
  • Niche differentiation