Abstract
1. Outcomes for butterfly conservation can hinge on interactions with host plants during early larval instars. Ontogenetic changes in larvae may cause predictors of survival to shift quickly over time. 2. Survival from instar to instar was measured for an endangered oligophagous butterfly, Euphydryas editha ssp. taylori (Taylor's checkerspot), which was experimentally released in the field on three host plants: Castilleja levisecta, Castilleja hispida, and Plantago lanceolata. Survival rates were quantified, from hatching to the second instar, from the second to the third instar, and from the third to the fourth instar. 3. This study tested whether host plant characteristics (degree of senescence and anthocyanin pigmentation) affected survival during each instar; the effects of oviposition timing and larval group size on survival were also tested, as these vary by group and could affect outcomes for larvae differently on different hosts. 4. Survival rates depended on the host species being consumed, mostly because of a disparity in survival during the transition from the second to the third instar. Survival was lowest on C. levisecta, intermediate on C. hispida, and highest on P. lanceolata. 5. Plant senescence, oviposition timing, and group size were predictors of survival, but their relevance depended on both the host plant being used and the instar being considered. 6. Host plant suitability can vary strongly both within and among species, changing quickly with caterpillar ontogeny during early instars.
Original language | English |
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Pages (from-to) | 742-753 |
Number of pages | 12 |
Journal | Ecological Entomology |
Volume | 43 |
Issue number | 6 |
DOIs | |
State | Published - Dec 2018 |
Bibliographical note
Funding Information:Our thanks to personnel at the Oregon Zoo, and inmates at the Mission Creek Correctional Center for Women, who helped provide eggs used in this study. S. Freed and D. Hays granted site access and logistical support for field work. L. Rafay, M. Bond, S. Erskine, S. Rich, K. Ricks, J. Yim, and R. Mecka served as field and laboratory technicians. Several members of the Taylor’s checkerspot recovery working group provided input on the design of this study, and T. Thomas and G. Canterbury (USFWS) coordinated the permitting process. Two anonymous reviewers, C. Torgersen, J. Ruesink, and M.D. Bowers provided input to this manuscript. This work was funded by the Joint Base Lewis-McChord Army Compatible Use Buffer Program and the National Science Foundation (DEB – 1556106).
Publisher Copyright:
© 2018 The Royal Entomological Society
Keywords
- Butterfly conservation
- Euphydryas editha taylori
- host plant suitability
- host switch
- novel interactions
- ontogenetic niche shift
ASJC Scopus subject areas
- Ecology
- Insect Science