Plant quality and local adaptation undermine relocation in a bog specialist butterfly

• Published in: Ecology and evolution 2013-02, Vol.3 (2), p.244-254
• Main Authors: Turlure, Camille, Radchuk, Viktoriia, Baguette, Michel, Meijrink, Mark, den Burg, Arnold, Vries, Michiel Wallis, Duinen, Gert‐Jan
• Format: Article
• Language: English
• Subjects: Adaptation; Applied ecology; Boloria aquilonaris; Butterflies & moths; Caterpillars; climate-change; Collapse; conservation; Cranberries; diversity; dynamics; Ecosystems; Environmental changes; evolutionary ecology; Extinction; Food; Growth rate; habitat; Host plants; insect‐plant interactions; lepidoptera; local adaptation; Nitrogen; nitrogen deposition; Original Research; phenotypic plasticity; Population; Population decline; Population viability; Populations; Quality; Reintroduction; reintroduction biology; Relocation; selection; Solution strengthening; Species; Vaccinium; Vaccinium oxycoccos
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.427

The butterfly Boloria aquilonaris is a specialist of oligotrophic ecosystems. Population viability analysis predicted the species to be stable in Belgium and to collapse in the Netherlands with reduced host plant quality expected to drive species decline in the latter. We tested this hypothesis by rearing B. aquilonaris caterpillars from Belgian and Dutch sites on host plants (the cranberry, Vaccinium oxycoccos). Dutch plant quality was lower than Belgian one conferring lower caterpillar growth rate and survival. Reintroduction and/or supplementation may be necessary to ensure the viability of the species in the Netherlands, but some traits may have been selected solely in Dutch caterpillars to cope with gradual changes in host plant quality. To test this hypothesis, the performance of Belgian and Dutch caterpillars fed with plants from both countries were compared. Dutch caterpillars performed well on both plant qualities, whereas Belgian caterpillars could not switch to lower quality plants. This can be considered as an environmentally induced plastic response of caterpillars and/or a local adaptation to plant quality, which precludes the use of Belgian individuals as a unique solution for strengthening Dutch populations. More generally, these results stress that the relevance of local adaptation in selecting source populations for relocation may be as important as restoring habitat quality. Reintroduction and/or supplementation may be necessary to ensure the viability of Boloria aquilonaris, a specialist butterfly from oligotrophic ecosystems, in the Netherlands. However, only Dutch caterpillars are able to cope with the lower host plant quality prevailing in the Netherlands, which precludes the use of Belgian caterpillars as a unique solution for strengthening Dutch populations. Practically, these results stress that the relevance of local adaptation in selecting source populations for relocation may be as important as restoring habitat quality.