Biological Invasions

, Volume 13, Issue 1, pp 93–104 | Cite as

Throwing the baby out with the bathwater: does laurel forest restoration remove a critical winter food supply for the critically endangered Azores bullfinch?

  • Ricardo S. Ceia
  • Hugo L. Sampaio
  • Sandra H. Parejo
  • Ruben H. Heleno
  • Maria L. Arosa
  • Jaime A. Ramos
  • Geoff M. Hilton
Original Paper


The invasive Clethra arborea has a dual-role in the diet of the Azores bullfinch, a critically endangered bird species endemic to the island of São Miguel (Azores, Portugal). This is a crucial winter food resource but it lowers the availability of native laurel forest species that compose most of the bird’s diet throughout the year. The removal of this and other invasive alien species is part of current laurel forest habitat restoration programmes, disregarding the impact on the Azores bullfinch population. In order to evaluate the first responses of the Azores bullfinch to habitat restoration, we studied bird diet, foraging behaviour, food availability and habitat occupancy in managed (without C. arborea) and control areas. Significant increases in the availability of native food resources in managed areas were noticeable in the diet, particularly the intake of Ilex perado ssp. azorica and Prunus lusitanica ssp. azorica flower buds. In most of the studied months birds heavily used and foraged in managed over control areas. The one exception was in December, when a resource-gap occurred in managed areas, which may be overcome in the short-term due to re-establishment of native plants following removal of invasive aliens.


Azores Clethra arborea Endangered species Habitat restoration Laurel forest Pyrrhula murina 


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Ricardo S. Ceia
    • 1
  • Hugo L. Sampaio
    • 1
  • Sandra H. Parejo
    • 1
  • Ruben H. Heleno
    • 2
  • Maria L. Arosa
    • 3
    • 5
  • Jaime A. Ramos
    • 3
  • Geoff M. Hilton
    • 4
    • 6
  1. 1.Portuguese Society for the Study of BirdsLisbonPortugal
  2. 2.Institut Mediterrani d’Estudis Avançats (CSIC-UIB)Esporles, MallorcaSpain
  3. 3.Institute of Marine Research (IMAR/CMA), Department of Life SciencesUniversity of CoimbraCoimbraPortugal
  4. 4.Royal Society for the Protection of Birds (RSPB)The Lodge, Sandy, BedsUnited Kingdom
  5. 5.Centre for Functional Ecology, Department of Life SciencesUniversity of CoimbraCoimbraPortugal
  6. 6.Wildfowl & Wetlands TrustSlimbridge, GlosUK

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