Abstract
The Canary Islands are home to a large variety of endemic fauna. The Canary shrew (Crocidura canariensis) has a distribution restricted to Fuerteventura, Lanzarote and the islets of Lobos and Montaña Clara. One of the main threats to the insular fauna is the arrival of exotic species. The greater white-toothed shrew (Crocidura russula) is an easily transportable animal and a potential competitor for C. canariensis. Therefore, C. russula should be taken into account in the management protocols for invasive species. One of the most easily applicable techniques for detecting shrews is the analysis of pellets. This study aims to assess which morphological characters are diagnostic and easy to use when identifying both species of shrews. For this purpose, a blind specific assignment has been made using seven previously described characters and another three added in the present study. The results show that the observer’s experience did not improve the correct identification rate and that only three of the evaluated characters have a high discriminant capacity. Finally, it was found that the combined use of the maximum number of characters and the identification by two independent observers reduces the probability of making a mistake in the determination to minimum values.
Acknowledgments
The authors would like to thank Beneharo Rodríguez (GOHNIC) for the cession of owl pellets collected on Montaña Clara islet. Logistic and technical support were provided by scientific collection of Doñana Biological Station ICTS-RBD.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
References
Aubry, K.B., Raley, C.M., and McKelvey, K.S. (2017). The importance of data quality for generating reliable distribution models for rare, elusive, and cryptic species. PLoS One 12: e0179152. https://doi.org/10.1371/journal.pone.0179152.Search in Google Scholar
Bellard, C., Cassey, P., and Blackburn, T.M. (2016). Alien species as a driver of recent extinctions. Biol. Lett. 12: 20150623. https://doi.org/10.1098/rsbl.2015.0623.Search in Google Scholar
Biedma, L., Román, J., Calzada, J., Friis, G., and Godoy, J.A. (2018). Phylogeography of Crocidura suaveolens (Mammalia: Soricidae) in Iberia has been shaped by competitive exclusion by C. russula. Biol. J. Linn. Soc. 123: 81–95. https://doi.org/10.1093/biolinnean/blx126.Search in Google Scholar
Biedma, L., Román, J., Godoy, J.A., and Calzada, J. (2019). Using owl pellets to infer habitat associations and clarify the regional distribution of a cryptic shrew. J. Zool. 308: 139–148. https://doi.org/10.1111/jzo.12660.Search in Google Scholar
Bover, P., Parpal, L., Pons, J., and Alcover, J.A. (2012). Evidence for a recent introduction of Crocidura russula (Mammalia, Eulipotyphla, Soricomorpha) in Mallorca (Balearic Islands, Western Mediterranean Sea). Mammalia 76: 113–116. https://doi.org/10.1515/mamm.2011.101.Search in Google Scholar
Bradsworth, N., White, J.G., Isaac, B., and Cooke, R. (2017). Species distribution models derived from citizen science data predict the fine scale movements of owls in an urbanizing landscape. Biol. Conserv. 213, Part A: 27–35. https://doi.org/10.1016/j.biocon.2017.06.039.Search in Google Scholar
Burnham, K.P., Anderson, D.R., and Huyvaert, K.P. (2011). AIC model selection and multimodel inference in behavioral ecology: some background, observations, and comparisons. Behav. Ecol. Sociobiol. 65: 23–35. https://doi.org/10.1007/s00265-010-1029-6.Search in Google Scholar
Calzada, J. and Román, J. (2017). EgaEduca. Una herramienta didáctica de investigación con egagrópilas. Vicerrectorado de calidad y formación de la Universidad de Huelva, Huelva, Available at: <http://www.uhu.es/egaeduca/ficha-5-c%C3%B3mo-diferenciar-entre-las-dos-especies-de-musara%C3%B1as-de-dientes-blancos-del-g%C3%A9nero-crocidura>.Search in Google Scholar
Dubey, S., Cosson, J.F., Magnanou, E., Vohralík, V., Benda, P., Frynta, D., Hutterer, R., Vogel, V., and Vogel, P. (2007). Mediterranean populations of the lesser white-toothed shrew (Crocidura suaveolens group): an unexpected puzzle of Pleistocene survivors and prehistoric introductions. Mol. Ecol. 16: 3438–3452. https://doi.org/10.1111/j.1365-294X.2007.03396.x.Search in Google Scholar
Early, R., Bradley, A.B., Dukes, J.S., Lawler, J.J., Olden, J.D., Blumenthal, D.M., Gonzalez, P., Grosholz, E.D., Ibañez, I., Miller, L.P., et al. (2016). Global threats from invasive alien species in the twenty-first century and national response capacities. Nat. Commun. 7: 12485. https://doi.org/10.1038/ncomms12485.Search in Google Scholar
Eckrich, C.A., Flaherty, E.A., and Ben-David, M. (2017). Functional and numerical responses of shrews to competition vary with mouse density. PLoS One 13: e0189471. https://doi.org/10.1371/journal.pone.0189471.Search in Google Scholar
Martín, A., Hutterer, R., and Corbet, G.B. (1984). On the presence of shrews (Soricidae) in the Canary Islands. Bonn. Zool. Beitr. 35: 5–14.Search in Google Scholar
McDevitt, A.D., Montgomery, W.I., Tosh, D.G., Lusby, J., Reid, N., White, T.A., McDevitt, C.D., O’Halloran, J., Searle, J.B., and Yearsley, J.M. (2014). Invading and Expanding: range dynamics and ecological consequences of the greater white-toothed shrew (Crocidura russula) invasion in Ireland. PLoS One 9: e100403. https://doi.org/10.1371/journal.pone.0100403.Search in Google Scholar
Morris, P.A. and Harper, J.F. (1965). The occurrence of small mammals in discarded bottles. Proc. Zool. Soc. Lond. 145: 148–153. https://doi.org/10.1111/j.1469-7998.1965.tb02010.x.Search in Google Scholar
Hutterer, R., López-Jurado, L.F., and Vogel, P. (1987). The shrews of the eastern Canary Islands: a new species (Mammalia: Soricidae). J. Nat. Hist. 21: 1347–1357. https://doi.org/10.1080/00222938700770851.Search in Google Scholar
Palomo, L.J., Gisbert, J., and Blanco, J.C. (2007). Atlas y Libro Rojo de los mamíferos silvestres de España. Dirección General para la Biodiversidad-SECEM-SECEMU, Madrid, p. 588.Search in Google Scholar
Poitevin, F., Catalan, J., Fons, R., and Croset, H. (1987). Biologie évolutive des populations Ouest-Européennes de Crocidures (Mammalia, Insectivora). II: ecologie comparée de Crocidura russula Hermann, 1780 et de Crocidura suaveolens Pallas, 1811 dans le midi de la France et en Corse: rôle probable de la compétition dans le partage des milieux. Revue d’Ecologie (Lla Terre et la Vie) 42: 32–58.10.3406/revec.1987.5394Search in Google Scholar
Rando, J.C., Alcover, J.A., Michaux, J., Hutterer, R., and Navarro, J.F. (2012). Late-Holocene asynchronous extinction of endemic mammals on the eastern Canary Islands. Holocene 22: 801–808. https://doi.org/10.1177/0959683611430414.Search in Google Scholar
Russell, J.C., Meyer, J.Y., Holmes, N.D., and Pagad, S. (2017). Invasive alien species on islands: impacts, distribution, interactions and management. Environ. Conserv. 44: 359–370. https://doi.org/10.1017/S0376892917000297.Search in Google Scholar
SAS Institute Inc. (2012). What’s new in SAS® 9.3. SAS Institute Inc., Cary, North Carolina.Search in Google Scholar
Schuster, C. (2014). Distribución de la musaraña canaria (Crocidura canariensis) en Fuerteventura, Islas Canarias. Galemys 26: 77–83. https://doi.org/10.7325/Galemys.2014.A8.Search in Google Scholar
Sullivan, B.L., Wood, C.L., Iliff, M.J., Bonney, R.E., Fink, D., and Kelling, S. (2009). eBird: a citizen-based bird observation network in the biological sciences. Biol. Conserv. 142: 2282–2292. https://doi.org/10.1016/j.biocon.2009.05.006.Search in Google Scholar
Tollington, S., Turbé, A., Rabitsch, W., Groombridge, J.J., Scalera, R., Essl, F., and Shwartz, A. (2017). Making the EU legislation on invasive species a conservation success. Conserv. Lett. 10: 112–120. https://doi.org/10.1111/conl.12214.Search in Google Scholar
Torre, I., Bosch, M., and Arrizabalaga, A. (1998). Botellas de uso doméstico como trampas selectivas para micromamíferos. Galemys 10: 53–59.Search in Google Scholar
Torre, I., Bastardas-Llabot, J., Arrizabalaga, A., and Díaz, M. (2020). Population dynamics of small endotherms under global change: greater white-toothed shrews Crocidura russula in Mediterranean habitats. Sci. Total Environ. 705: 135799. https://doi.org/10.1016/j.scitotenv.2019.135799.Search in Google Scholar
Tosh, D.G., Lusby, J., Montgomery, W.I., and O’Halloran, J. (2008). First record of greater white-toothed shrew Crocidura russula in Ireland. Mammal Rev. 38: 321–326. https://doi.org/10.1111/j.1365-2907.2008.00130.x.Search in Google Scholar
Vantieghem, P., Maes, D., Kaiser, A., and Merckx, T. (2017). Quality of citizen science data and its consequences for the conservation of skipper butterflies (Hesperiidae) in Flanders (northern Belgium). J. Insect Conserv. 21: 451–463. https://doi.org/10.1007/s10841-016-9924-4.Search in Google Scholar
Vogel, P. (1999). Colonisation capacity of the Greater white-toothed shrew Crocidura russula: an experimental study. Säugetierkund Mitt 44: 38–47.Search in Google Scholar
Vogel, P., Cosson, J.F., and López-Jurado, L.F. (2003). Taxonomic status and origin of the shrews (Soricidae) from the Canary Islands inferred from a mtDNA comparison with the European Crocidura species. Mol. Phylogenetics Evol. 27: 271–282. https://doi.org/10.1016/S1055-7903(02)00403-7.Search in Google Scholar
Wilson, D.E. and Mittermeier, R.A. (2018). Handbook of the mammals of the world – volume 8: insectivores, sloths and colugos. Lynx Edicions, Barcelona.Search in Google Scholar
Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/mammalia-2020-0043).
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