San Diego Management & Monitoring Program


Hermes Copper Butterfly Surveys and Translocation Efforts - Task 8: 2021 Harbison’s Dun Skipper Adult Surveys

Type: report

Article abstract: This report summarizes our survey efforts of 2021. Additional efforts for this project/task are planned for 2022 and will include a marking study to calibrate transect counts with population size estimates, and quantify habitat preferences. In 2021, surveys for Harbison’s dun skipper adults were conducted to assess year to year variation in population size and update the status of each local population/site. Surveys focused on the relatively small geographic area where skippers were observed in past years. In 2013- 2017, 14 sites had confirmed observations of Harbison’s dun skipper adults. All but one of these sites were surveyed in 2021, with Harbison’s dun skipper adults observed at only six sites. Population sizes at those six sites were similar to the smallest population sizes recorded during the 2013-2017 surveys. Overall, transect counts (visual observations) continue to describe small populations when skippers are present. However, the large size and uneven terrain of some riparian oak woodlands, patchy distribution of adult skippers, and shifting locations of San Diego sedge present challenges to accurately categorizing presence/absence and relative population sizes. (SANDAG TransNet EMP Contract #5005783)

Number of pages: 14

Authors: Marschalek, Dan;

Day: 31

Month: December

Year: 2021

Notes: SANDAG TransNet EMP Contract #: 5005783

Prepared for: San Diego Association of Governments;

Prepared by: University of Central Missouri;

Keywords: Harbison's dun skipper; Harbisons dun skipper;

Species: Harbison's Dun Skipper

Projects: