Environmental Management

, Volume 61, Issue 5, pp 875–883 | Cite as

Assessment of Detection Methods and Vegetation Associations for Introduced Finlayson’s Squirrels (Callosciurus finlaysonii) in Italy

  • Leonardo Ancillotto
  • Tommaso Notomista
  • Emiliano Mori
  • Sandro Bertolino
  • Danilo Russo


Managing biological invasions requires rapid, cost-effective assessments of introduced species’ occurrence, and a good understanding of the species’ vegetation associations. This is particularly true for species that are elusive or may spread rapidly. Finlayson’s squirrel (Callosciurus finlaysonii) is native to Thailand and southeastern Asia, and two introduced populations occur in peninsular Italy. One of the two introduced populations is rapidly expanding, but neither effective monitoring protocols nor reliable information on vegetation associations are available. To fill this gap, we conducted visual surveys and hair tube sampling in a periurban landscape of southern Italy to compare the effectiveness of these two methods in assessing presence of Finlayson’s squirrel. We also determined the species’ association with vegetation types at detection locations and nesting sites. Both visual and hair tube sampling effectively assessed the species’ presence, but hair tubes resulted in fewer false absences. Moreover, when we controlled for the costs of labor and equipment, hair tubes were 33.1% less expensive than visual sampling. Presence of squirrels and their nests was positively correlated with shrub species richness, indicating that the occurrence of forests with well-developed understory may inhibit the spread of the species.


Callosciurus finlaysonii Early detection Hair tubes Nest selection Occupancy models 



We thank Alessia D’Auria for assisting with laboratory procedures. This project did not receive any specific funding. Thanks also go to the associate editor who handled our paper and two anonymous reviewers whose recommendations helped us to improve our manuscript greatly.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approval

All procedures performed in studies involving wild species were in accordance with the ethical standards of the Institutional or National Research Committee and with approved ethical standards.

Supplementary material

267_2018_1013_MOESM1_ESM.docx (23 kb)
Supplementary material


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Wildlife Research Unit, Dipartimento di AgrariaUniversità degli Studi di Napoli Federico IIPorticiItaly
  2. 2.Dipartimento di Biologia Strutturale e FunzionaleUniversità degli Studi di Napoli Federico IINapoliItaly
  3. 3.Unità di Ricerca di Ecologia ComportamentaleEtologia e Gestione della Fauna—Dipartimento di Scienze della Vita—Università di SienaSienaItaly
  4. 4.Dipartimento di Scienze della Vita e Biologia dei SistemiUniversità di TorinoTorinoItaly
  5. 5.School of Biological SciencesUniversity of BristolBristolUK

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