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Mammalian Biology

, Volume 81, Issue 4, pp 365–371 | Cite as

Weight operated see-saw feeding hoppers are not selective for red squirrels when greys are present

  • Simone Lioy
  • Emiliano Mori
  • Lucas A. Wauters
  • Sandro BertolinoEmail author
Original investigation

Abstract

The competition for food resources between the native red squirrel and the introduced American Eastern grey squirrel is well known, and can lead to the extinction of the native species. Providing supplementary food resources for the red squirrel, by adopting selective feeding hoppers, has been proposed as a possible support for the short term conservation of native populations, but studies that investigate its effectiveness have not yet been performed. In this study we evaluate the effectiveness of the feeding hoppers, in terms of selectivity towards the smaller native species, quantifying their utilization by the two species in sympatry and allopatry.

Feeding hoppers were not selective toward the native species. The success in the attempts to enter the hoppers was 95% for red and 86% for grey squirrels. The 50 hazelnuts provided during each feeding session, covering the energetic requirements of an individual for 6 (reds) or 3.5 (greys) days, were consumed in 45:43 ± 38:26 hh:mm by red and 31:07 ± 37:18 hh:mm by grey squirrels. The average weight of grey squirrels that entered the feeding hopper (490 ± 47 g) was higher than the calibration weight of the see-saw floor (400 g). This highlights that weight operated see-saw feeding hoppers are poorly selective. Structural modification of the feeding hoppers should be considered to obtain a real selectivity according to species before their implementation in the conservation of red squirrel populations.

However, feeding hoppers were selective in feeding squirrels when using hazelnuts, excluding the access to food supplies by other species. Therefore they can be used with success in supplementary feeding studies or behavioural and ecological studies, especially if combined with camera traps and individually marked animals.

Keywords

Activity pattern Competition Sciurus vulgaris Sciurus carolinensis Supplementary feeding 

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References

  1. Agostinelli, C., Lund, U, 2013. R Package ‘circular’: Circular Statistics (version 0.4-7) (accessed 23.03.16.) https://doi.org/r-forge.r-project.org/projects/circular/.
  2. Bertolino, S., 2008. Introduction of the American grey squirrel (Sciurus carolinensis) in Europe: a case study in biological invasion, Curr. Sci. India 95 (7), 903–906.Google Scholar
  3. Bertolino, S., Lurz, P., Sanderson, R.A., Rushton, S.P., 2008. Predicting the spread of the American grey squirrel (Sciurus carolinensis) in Europe: a call for a co-ordinated European approach, Biol. Conserv. 141, 2564–2575.CrossRefGoogle Scholar
  4. Bertolino, S., Girardello, M., Amori, G., 2014a. Identifying conservation priorities when data are scanty: a case study with small mammals in Italy. Mamm. Biol. 79, 349–356.CrossRefGoogle Scholar
  5. Bertolino, S., Montezemolo, N.C., Preatoni, D.G., Wauters, L.A., Martinoli, A., 2014b. A grey future for Europe: Sciurus carolinensis is replacing native red squirrels in Italy. Biol. Invasions 16 (1), 53–62.CrossRefGoogle Scholar
  6. Bertolino, S., Colangelo, P., Mori, E., Capizzi, D., 2015. Good for management, not for conservation: an overview of research, conservation and management of Italian small mammals, Hystrix 26, 25–35.Google Scholar
  7. Bosch, S., Lurz, P.W.W., 2012. The Eurasian Red Squirrel. Westarp Wissenschaften, Hohenwarsleben, Germany.Google Scholar
  8. Bosch, S., Spiessl, M., Müller, M., Lurz, P.W.W., Haalboom, T., 2015. Mechatronics meets biology: experiences and first results with a multipurpose small mammal monitoring unit used in red squirrel habitats, Hystrix 26, 169–172.Google Scholar
  9. Bryce, J.M., Speakman, J.R., Johnson, P.J., Macdonald, D.W., 2001. Competition between Eurasian red and introduced Eastern grey squirrels: the energetic significance of body-mass differences, Proc. R. Soc. Lond. 268, 1731–1736.CrossRefGoogle Scholar
  10. Collen, B., Böhm, M., Kemp, R., Baillie, J.E.M., 2012. Spineless: Status and Trends of the World’s Invertebrates. Zoological Society of London, London.Google Scholar
  11. Dagnall, J., Gurnell, J., Pepper, H., 1998. Bark-stripping by grey squirrels in state forests of the United Kingdom: a review, Ecology and evolutionary biology of tree squirrels. Virginia Museum of Natural History, Special Publication 6, 249–261.Google Scholar
  12. Di Febbraro, M., Lurz, P.W.W., Genovesi, P., Maiorano, L., Girardello, M., Bertolino, S., 2013. The use of climatic niches in screening procedures for introduced species to evaluate risk of spread: a case with the American Eastern Grey Squirrel, PLoS One 8 (7), 1–10.CrossRefGoogle Scholar
  13. Everest, D.J., Shuttleworth, C.M., Stidworthy, M.F., Grierson, S.S., Duff, J.P., Kenward, R.E., 2014. Adenovirus: an emerging factor in red squirrel Sciurus vulgaris conservation, Mamm. Rev. 44, 225–233.CrossRefGoogle Scholar
  14. Goheen, J.R., Swihart, R.K., 2003. Food-hoarding behavior of gray squirrels and North American red squirrels in the central hardwoods region: implications for forest regeneration, Can. J. Zool. 81, 1636–1639.CrossRefGoogle Scholar
  15. Gurnell, J., 1996. The grey squirrel in Britain: problems for management and lessons for Europe. In: Proceedings of the I European Congress of Mammalogy. Museu Bocage, Lisboa, pp. 67–81.Google Scholar
  16. Gurnell, J., Pepper, H.W., 1991. Conserving the Red Squirrel. Forestry Commission Research Division. Res. Inf. Note, 205.Google Scholar
  17. Gurnell, J., Pepper, H.W., 1993. A critical look at conserving the British Red Squirrel Sciurus vulgaris, Mamm. Rev. 23, 127–137.CrossRefGoogle Scholar
  18. Gurnell, J., Wauters, L.A., Lurz, P.W.W., Tosi, G., 2004. Alien species and interspecific competition: effects of introduced eastern grey squirrels on red squirrel population dynamics, J. Anim. Ecol. 73, 26–35.CrossRefGoogle Scholar
  19. Gurnell, J., Lurz, P.W.W., Bertoldi, I.W., 2014. The changing patterns in the distribution of red and grey squirrels in the North of England and Scotland between 1991 and 2010 based on volunteer surveys, Hystrix 25 (2), 83–89.Google Scholar
  20. Gurnell, J., Lurz, P.W.W., Wauters, L.A., 2015. Years of interaction and conflict in Europe: competition between Eurasian red squirrels and North American grey squirrels. In: Shuttleworth, C., Lurz, P.W.W., Haywood, M.W. (Eds.), Red squirrels: Ecology, Conservation and Management in Europe. European Squirrel Initiative, pp. 19–37.Google Scholar
  21. Harris, S., Yalden, D.W., 2008. Mammals of the British Isles. In: Handbook, 4th ed. The Mammal Society, Southampton.Google Scholar
  22. Huxley, L., 2003. The grey squirrel review—profile of an invasive alien species grey squirrel (Sciurus carolinensis). Eur. Squirrel Initiative Dorset.Google Scholar
  23. Kenward, R.E., Hodder, K.H., 1998. Red squirrels (Sciurus vulgaris) released in conifer woodland: the effects of source habitat, predation and interactions with grey squirrels (Sciurus carolinensis), Zool. Soc. Lond. 244, 23–32.CrossRefGoogle Scholar
  24. Kenward, B., Kenward, R.E., Kacelnik, A., 2005. An automatic technique for selective feeding and logging of individual wild squirrels, Ethol. Ecol. Evol. 17, 271–277.CrossRefGoogle Scholar
  25. Klenner, W., Krebs, C.J., 1991. Red squirrel population dynamics I. The effect of supplemental food on demography. J. Anim. Ecol. 60(3), 961–978.Google Scholar
  26. Koprowski, J.L., 1994. Sciurus carolinensis, Mamm. Species 480, 1–9.Google Scholar
  27. Lowe, S., Browne, M., Boudjelas, S., De Poorter, M., 2000.100 of the world’s worst invasive alien species. A selection from the Global Invasive Species Database. The Invasive Species Specialist Group (ISSG) a specialist group of the Species Survival Commission (SSC) of the World Conservation Union (IUCN). First published as special lift-out in Aliens 12, December 2000.Google Scholar
  28. Lurz, P.W.W., Gurnell, J., Magris, L., 2005. Sciurus vulgaris, Mamm. Species 769, 1–10.CrossRefGoogle Scholar
  29. Macdonald, I.M.V., 1997. Field experiments on duration and precision of grey and red squirrel spatial memory, Anim. Behav. 54, 879–891.PubMedCrossRefGoogle Scholar
  30. Mahan, R.P., 1991. Circular Statistical Methods: Applications in Spatial and Temporal Performance Analysis. United States Army Research Institute for the Behavioral and Social Sciences, special report 16.Google Scholar
  31. Manchester, S.J., Bullock, J.M., 2000. The impacts of non-native species on UK biodiversity and the effectiveness of control, J. Appl. Ecol. 37, 845–864.CrossRefGoogle Scholar
  32. Martinoli, A., Bertolino, S., Preatoni, D.G., Balduzzi, A., Marsan, A., Genovesi, P., Tosi, G., Wauters, L.A., 2010. Headcount 2010: the multiplication of the grey squirrel introduced in Italy, Hystrix 21 (2), 127–136.Google Scholar
  33. National Agricultural Library, 2015. USDA National Nutrient Database for Standard Reference, Release 27, Report Date: February 03, 2015.Google Scholar
  34. Parrott, D., Quy, R., Van Driel, K., Lurz, P., Rushton, S., Gurnell, J., Aebischer, N., Reynolds, J., 2009. Review of Red Squirrel Conservation Activity in Northern England. Natural England Contract No. 08/09/N/004. 2009. Report by Central Science Laboratory and Newcastle University.Google Scholar
  35. Pepper, H.W., 1993. Red squirrel supplementary food hopper. Forestry Commission Research Division. Res. Inf. Note, 235.Google Scholar
  36. R Core Team, 2015. R: A language and environment for statistical computing R Foundation for Statistical Computing, Vienna, Austria (accessed 15.10.15.) https://doi.org/www.R-project.org/.
  37. R Studio Team, 2015. RStudio: Integrated Development for R. R Studio, Inc., Boston, MA (accessed 15.10.15.) https://doi.org/www.rstudio.com/.Google Scholar
  38. Romeo, C., Ferrari, N., Rossi, C., Everest, D.J., Grierson, S.S., Lanfranchi, P., Martinoli, A., Saino, N., Wauters, LA., Hauffe, H.C., 2014a. Ljungan virus and an adenovirus in Italian squirrel populations. J. Wildl. Dis. 50, 409–411.PubMedCrossRefGoogle Scholar
  39. Romeo, C, Wauters, L.A., Ferrari, N., Lanfranchi, P., Martinoli, A., Pisanu, B., Preatoni, D.G., Saino, N., 2014b. Macroparasite fauna of alien grey squirrel (Sciurus carolinensis): composition, variability and implications for native species. PLoS One 9 (2), e88002.PubMedPubMedCentralCrossRefGoogle Scholar
  40. Romeo, C., Ferrari, N., Lanfranchi, P., Saino, N., Santicchia, F., Martinoli, A., Wauters, L.A., 2015. Biodiversity threats from outside to inside: effects of alien grey squirrel (Sciurus carolinensis) on helminth community of native red squirrel (Sciurus vulgaris), Parasitol. Res. 114, 2621–2628.PubMedCrossRefPubMedCentralGoogle Scholar
  41. Rovero, F., Zimmermann, F., Berzi, D., Meek, P., 2013. Which camera trap type and how many do I need: a review of camera features and study designs for a range of wildlife research applications, Hystrix 24, 148–156.Google Scholar
  42. Rushton, S.P., Lurz, P.W.W., Gurnell, J., Fuller, R., 2000. Modelling the spatial dynamics of parapoxvirus disease in red and grey squirrels: a possible cause of the decline in the red squirrel in the United Kingdom? J, Appl. Ecol. 37, 997–1012.CrossRefGoogle Scholar
  43. Sainsbury, A.W., Nettleton, P., Gilray, J., Gurnell, J., 2000. Grey squirrels have high seroprelavalence to a parapoxvirus associated with deaths in red squirrels, Anim. Conserv. 3, 229–233.CrossRefGoogle Scholar
  44. Schuchert, P., Shuttleworth, C.M., McInnes, C.J., Everest, D.J., Rushton, S.P., 2014. Landscape scale impacts of culling upon a European grey squirrel population: can trapping reduce population size and decrease the threat of squirrel pox virus infection forthe native red squirrel? Biol, Invasions 16, 2381–2391.CrossRefGoogle Scholar
  45. Shuttleworth, C, Lurz, P.W.W., Geddes, N., Browne, J., 2012. Integrating red squirrel (Sciurus vulgaris) habitat requirements with the management of pathogenic tree disease in commercial forests inthe UK, For. Ecol. Manag. 279, 167–175.CrossRefGoogle Scholar
  46. Shuttleworth, C.M., Everest, J.D., McInnes, C.J., Greenwood, A., Jackson, N.L, Rushton, S., Kenward, R.E., 2014. Inter-specific viral infections: can the management of captive red squirrel collections help inform scientific research? Hystrix 25, 18–24.Google Scholar
  47. Shuttleworth, C.M., Lurz, P.W.W., Halliwell, E.C., 2015a. Shared Experience of Red Squirrel Conservation Practice. European Squirrel Initiative (accessed 11.03.16.) https://doi.org/www.redsquirrels.info/wp-content/uploads/2015/09/Red-Squirrel-Conservation-eBook.pdf.
  48. Shuttleworth, C, Lurz, P., Hayward, M., Bertolino, S., 2015b. Developing integrated red squirrel conservation in Europe. In: Shuttleworth, C., Lurz, P., Hayward, M. (Eds.), Red Squirrels: Ecology, Conservation & Management in Europe, 317–328. European Squirrel Initiative, Woodbridge, Suffolk UK.Google Scholar
  49. Shuttleworth, C, Signorile, LA, Everest, D.J., Duff, J.P., Lurz, P.W.W., 2015c. Assessing causes and significance of red squirrel (Sciurus vulgaris) mortality during regional population restoration: an applied conservation perspective. Hystrix,  https://doi.org/10.4404/hystrix-26.2-11166, Online first.
  50. Simberloff, D., 2005. Non-native species do threaten the natural environment! J, Agric. Environ. Ethics 18, 595–607.CrossRefGoogle Scholar
  51. Tattoni, C, Preatoni, D., Lurz, P., Rushton, S., Tosi, G., Bertolino, S., Martinoli, A., Wauters, L.A., 2006. Modelling the expansion of a grey squirrel population: implications for squirrel control, Biol. Invasions 8, 1605–1619.CrossRefGoogle Scholar
  52. Tompkins, D. M., White, A.R., Boots, M., 2003. Ecological replacement of native red squirrels by invasive greys driven by disease, Ecol. Lett. 6 (3), 189–196.CrossRefGoogle Scholar
  53. Tonkin, J.M., 1983. Activity patterns of the Red squirrel (Sciurus vulgaris), Mamm. Rev. 13, 99–111.CrossRefGoogle Scholar
  54. Vié, J.C., Hilton-Taylor, C., Stuart, S.N., 2009. Wildlife in a changing world: an analysis of the 2008 IUCN Red List of threatened species. IUCN.Google Scholar
  55. Wauters, L.A., 2000. Squirrels—medium-sized granivores in woodland habitats. In: Halle, S., Stenseth, N.C. (Eds.), Activity Patterns in Small Mammals: A Comparative Ecological Approach. Ecological Studies 141. Springer-Verlag, Heidelberg, Germany.Google Scholar
  56. Wauters, L.A., Dhondt, A.A., 1987. Activity budget and foraging behaviour of the red squirrel (Sciurus vulgaris Linnaeus, 1758) in a coniferous habitat, Z. Säugetierkd. 52, 341–352.Google Scholar
  57. Wauters, L.A., Swinnen, C, Dhondt, A.A., 1992. Activity budget and foraging behaviour of red squirrels (Sciurus vulgaris) in coniferous and deciduous habitats, J. Zool. 227, 71–86.CrossRefGoogle Scholar
  58. Wauters, L.A., Gurnell, J., Martinoli, A., Tosi, G., 2001. Does interspecific competition with introduced grey squirrels affect foraging and food choice of Eurasian red squirrels? Anim, Behav. 61, 1079–1091.CrossRefGoogle Scholar
  59. Wauters, L.A., Tosi, G., Gurnell, J., 2002a. Interspecific competition in tree squirrel: do introduced grey squirrels (Sciurus carolinensis) deplete tree seeds hoarded by red squirrels (S. vulgris)? Behav. Ecol. Sociobiol. 51, 360–367.CrossRefGoogle Scholar
  60. Wauters, L.A., Gurnell, J., Martinoli, A., Tosi, G., 2002b. Interspecific competition between native Eurasian red squirrels and alien grey squirrels: does resource partitioning occur? Behav. Ecol. Sociobiol. 52 (4), 332–341.CrossRefGoogle Scholar

Copyright information

© Deutsche Gesellschaft für Säugetierkunde 2016

Authors and Affiliations

  • Simone Lioy
    • 1
  • Emiliano Mori
    • 1
  • Lucas A. Wauters
    • 2
  • Sandro Bertolino
    • 1
    Email author
  1. 1.Department of Agriculture, Forest and Food SciencesUniversity of TurinGrugliasco, TurinItaly
  2. 2.Department of Theoretical and Applied SciencesUniversity of InsubriaVareseItaly

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