Resource selection in an endangered butterfly: Females select native nectar species
Abstract
Management of at-risk species requires attention to species-specific resource requirements. In butterflies, lack of information on resource selection in adults limits conservation. We investigated nectar plant use and selection by Fender's blue butterfly (Plebejus [= Icaricia] icarioides fenderi), a species endangered by loss of over 99% of prairie habitat in Oregon's Willamette Valley, USA. We observed 156 male and 75 female nectaring bouts by Fender's blue at 3 sites across the range of the species concurrent with weekly surveys of nectar availability. Overall, 53% of nectar uses by males and 20% of uses by females were on non-native species. Of the 24 plant species used by males and females, 8 species accounted for 86% of uses. Tests of resource selection (Wilkes λ) using compositional analysis for these 8 species were significant, indicating that nectar resources were used selectively, rather than in proportion to availability. Females selected native nectar species over non-native species, whereas patterns for males were less clear. This study highlights the importance of differentiating between males and females when examining habitat requirements for endangered species. In addition, understanding how specific non-native species are used by endangered species will help managers decide when they should be removed or conserved.
- Publication:
-
The Journal of Wildlife Management
- Pub Date:
- January 2016
- DOI:
- 10.1002/jwmg.987
- Bibcode:
- 2016JWMan..80..171T