The distribution of exotic species bearing fruits may depend in part on their palatability to birds, because species attracting a more diverse array of dispersers should broadcast seed to a wider range of habitats, including those otherwise assumed to represent refuges from exotic species invasion, such as small islands. To test these ideas, we compared the palatability of 11 exotic shrub species to their occurrence on 91 islands of varying size and isolation in the Gulf Islands of British Columbia, Canada and the San Juan Islands of Washington, USA. The estimated palatability of fruits for 10 common frugivorous birds was positively related to the number of islands on which they occurred. Rubus armeniacus and R. laciniatus were the most widely consumed exotic species and the only such species prevalent on small islands, suggesting that they have benefited by attracting a wide array of frugivores that have, in turn, facilitated their rapid colonization of the region. Our results suggest that protecting small islands from human visitation will be insufficient to prevent exotic species establishment and the loss of native biodiversity.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 18 • No. 4