Dispersal behavior and habitat variation of Taylor’s checkerspot butterfly
This project is intended to provide information about the Taylor’s checkerspot butterfly (Euphydryas editha taylori) habitat and dispersal behavior to support management of existing populations, habitat connectivity, reserve design, and overall recovery. This project addresses
This project is intended to provide information
about the Taylor’s checkerspot butterfly (Euphydryas editha taylori) habitat and dispersal behavior to support management of existing populations, habitat connectivity, reserve design, and overall recovery. This project addresses two project objectives, measurements of 1. dispersal behavior and 2. habitat characteristics. To meet objective 1, dispersal behavior, we conducted observations at one population in Oregon and three in Washington. We focused on two aspects of dispersal behavior, frequency of movement between habitat patches and responses to habitat edges. For objective 2, habitat characteristics, we measured physical and biological habitat attributes at a range of sites in Oregon, Washington, and British Columbia. This report contains information on progress to date.
Results
- Taylor’s checkerspot butterfly is capable of flying over numerous potential habitat barriers, including roads, shrubs, changes in topography and even forests 20‐30 m in height.
- Males were observed through mark‐recapture methods to move between habitat patches in a forested area in Oregon, in some cases crossing a band of trees more than 100 m across.
- Frequency of travel by males between meadows in Oregon was generally correlated with patch distance. One exception was that butterflies were more likely to move from a low resource patch to high resource patch.
- Taylor’s checkerspot populations in Oregon, South Puget Sound, and Olympic Peninsula occur in different plant communities in each region. These plant communities differ in terms of species present as well as primary functional groups.
– Abundance of plant litter and bare ground varied substantially among populations and do not appear to be strong determinants of habitat quality for this species at the site scale.
– In addition, the primary host plant and nectar plants at individual sites varied substantially, suggesting that the species may be able to adapt to new resource environments.
- Reserve design may best focus on:
- Connectivity between habitat patches, such as opening corridors through forests between meadows to encourage butterfly movement between resource patches
- Improvement of host plant population size, either through planting of Plantago lanceolata or Castilleja hispida, or both to provide increased host diversity.
- Increased abundance and diversity of nectar resources.
