Climate Impacts on Nectar Resources of the Endangered Fender’s Blue Butterfly

  • U.S. Fish & Wildlife Service
  • Joint Base Lewis McChord
In Progress

Pollinators are threatened by many climate change impacts, but resource mismatches are an emerging and important area of research, especially for short-lived pollinators. Across the globe, the timing of the flower production of plants is changing due to climate change, and insect emergence dates are also shifting. This phenomenon, called phenological shifts, can lead to mismatches between an organism and the availability of its resources. For example, some butterflies may emerge after their favorite flower has finished blooming. 

This project will investigate if phenological shifts of butterflies and nectar communities will lead to a positive or negative change in resources for the Fender’s blue butterfly, which can utilize a broad range of plants but within a limited time frame. The Fender’s blue butterfly (Plebejus icarioides fenderi) is an endangered species that has been well-monitored since the 1990s and could be susceptible to resource mismatches given its short life span and sedentary tendencies.

This research project will finish evaluating the nectar resources for the near future based on the estimated timing changes of the butterflies and nectar plants, then create a nectar calculator that allows managers to evaluate individual patches of Fender’s blue habitat to ensure that the butterfly has access to proper resources as the climate continues to cause phenological shifts to occur. The nectar calculator will allow land managers to begin proactively managing for any negative impacts on the nectar resources, including seeding specific nectar plants that will provide nectar for the next 30 years, as opposed to seeding plants that are soon to phenologically mismatch with the Fender’s blue butterfly. Finally, researchers will conduct site evaluations of closely related blues (other Plebejus icarioides subspecies) and their nectar resources within Western Washington and Oregon to assess the potential impact of climate change on these blue butterflies in the region.