Deutschman Lab - San Diego State University

Harbison's Dun Skipper is restricted to southern Orange County and San Diego County, with no published records from Mexico. In addition to the restricted range, habitat loss associated with urbanization, pollution, recent wildfires of 2003 and 2007, and prolonged dry conditions over the last decade, pose important threats to the Harbison's dun skipper. Entomologists have expressed concern that the Harbison's dun skipper is at risk of extinction and it was previously given a Category 2 status by U.S. Fish & Wildlife Service.

Only two papers specific to the Harbison's Dun Skipper have been published so little is known about this subspecies. Adults are present during the early summer and remain relatively close to their only known host plant, San Diego Sedge (Carex spissa). Larvae construct a shelter (hibernacula) by attaching two to four leaves together where they can be found when not foraging.

The Harbison's Dun Skipper project is a description of the current status of the species in San Diego County. This includes an initial investigation into the range of the skipper (identifying suitable habitat followed by a comprehensive survey) as well as providing a baseline for preliminary work on both population status (landscape genetic study) and habitat requirements (initial habitat/occupancy modeling). It is expected that subsequent work will provide more insight into the status and trend of the subspecies as well as refine landscape genetic and habitat models for the skipper. The subsequent projects will benefit from the crucial baseline data collected during this initial phase of work.

Research Tasks

1. Document patches of host plant for the Harbison's Dun Skipper on conserved lands in San Diego County

2. Describe the distribution of Harbison's Dun Skipper on conserved lands in San Diego County

3. Describe the biology of adults, including flight season phenology, behavior, and nectar sources

4. Estimate population sizes

Lead Biologist: Daniel Marschalek

This project is funded by a grant from the California Department of Fish & Wildlife.