A resource-efficient procedure to improve planning of invasive cat management on inhabited islets

Biological Invasions volume 21, pages1817–1831(2019)Cite this article

Abstract

Cats (Felis silvestris catus) are one of the most pernicious invasive species on islands, being responsible for the decline and extinction of many vertebrate taxa. Eradications programs are a powerful tool to fight against cat impacts on islands, but their implementation requires planning and design to prevent failure. In that sense, gathering data on cat habitat use, abundance and trophic interactions provides key information to effectively design management actions. The present contribution presents a simple resource-efficient methodology using cat feces to assess cat distribution, density and trophic ecology on an inhabited islet. This information is essential in order to effectively organize trapping efforts and minimize subsequent impacts of other species if a control or eradication campaign is undertaken. Additionally, our research effort evaluated the potential influence of coastal and anthropic resources on cat diet, which can also provide useful information for planning aside management actions. Cat distribution on our model islet, La Graciosa, was ‘clumped’, presenting higher densities in anthropic areas (villages and farms). The invasive house mouse and the European rabbit were the main prey items, although native invertebrates, reptiles and birds were also consumed. Cats on La Graciosa ingested a large quantity of garbage, which was negatively correlated with distance from human settlements. Considering the low time and resource requirements of this methodology, and the useful basic ecological information it provides, it can be employed to make optimal management planning decisions for small inhabited islands where cat control or eradication programs are being considered.

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Acknowledgements

We are deeply thankful to the Organismo Autónomo de Parques Nacionales -in particular to Aurelio Centellas- for their collaboration, which greatly facilitated this research. We also thank Francisco J. Morata, Juan C. Morata, Noemí Rodríguez, Jeremías Cabrera and Jonay Cubas for their participation during fieldwork, and express our gratitude to Alberto García and Javier Luzardo from the NGO “Asociación Amigos de las Pardelas”, for their great support. Aurelio Martín (Department of Animal Biology of the University of La Laguna) and Juan Carlos Rando helped us in the identification of prey remains. We acknowledge the contribution of two anonymous reviewers from Biological Invasions, whose excellent review improved significantly the final version of this manuscript. This study was funded by the Cabildo of Lanzarote (1701.48000). MLD was funded by a program of Cabildo Insular de Tenerife, under the identification mark “Tenerife 2030” (P. INNOVA 2016-2021). JCP was funded by a Canary Islands Government PhD fellowship (TESIS 2017010051).

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  1. J. C. Piquet and E. S. Baumgartner have contributed equally to this work.

Affiliations

  1. Island Ecology and Evolution Research Group (IPNA-CSIC), Ave. Astrofísico Fco. Sánchez No. 3, 38206, San Cristóbal de La Laguna, Tenerife, Canary Islands, Spain

    J. C. Piquet, F. M. Medina, N. Díaz-Luis, H. López, M. Nogales & M. López-Darias

  2. School of Biological Sciences, College of Science and Engineering, University of Edinburgh, Edinburgh, UK

    E. S. Baumgartner

  3. Servicio de Medio Ambiente, Cabildo Insular de La Palma, Santa Cruz de La Palma, Canary Islands, Spain

    F. M. Medina

  4. C/ Jaime Ramos 3, 38206, San Cristóbal de La Laguna, Tenerife, Canary Islands, Spain

    J. Sevilla

  5. Asociación Amigos de las Pardelas, Edificio de Usos Múltiples de Bañaderos, C/ Océano Glacial Antártico 2, 35400, Arucas, Gran Canaria, Spain

    M. López-Darias

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  1. J. C. Piquet
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Piquet, J.C., Baumgartner, E.S., Medina, F.M. et al. A resource-efficient procedure to improve planning of invasive cat management on inhabited islets. Biol Invasions 21, 1817–1831 (2019). https://doi.org/10.1007/s10530-019-01941-x

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Keywords

  • Cat density
  • Conservation biology of islets
  • Ecological factors
  • Feeding habits
  • Felis silvestris catus
  • Invasive predator