Snowy plover monitoring in the Golden Gate National Recreation Area: Summary report 2015?2019

Abstract

This report summarizes results from five seasons, 2015?2019, of Golden Gate National Recreation Area?s western snowy plover (Charadrius nivosus nivosus) monitoring program. The goals of our monitoring program are to estimate trends in the overwintering snowy plover population size and distribution, as well as to track potential disturbance threats to snowy plovers. We surveyed Ocean Beach and Crissy Field for snowy plovers twice a week every other week, from 01-July 2015 to 13-May 2020. During each of the five years, we observed snowy plover counts that were higher than long-term average counts calculated from 1994 to 2019 on Ocean Beach, with a record maximum count of 106 plovers in 2015. We also observed higher-than-average numbers of snowy plovers on Crissy Field, ranging from a maximum count of six in 2017 to a record maximum count of 12 in 2019. Additional field seasons and analyses are necessary to determine population trends for these two beaches. Following recent use patterns at Ocean Beach, snowy plovers were primarily observed in the wider area of beach between Lawton and Lincoln streets. At Crissy Field, snowy plovers were only found in the Wildlife Protection Area to the east of the US Coast Guard pier. Leash non-compliance rates at Ocean Beach remain high, approaching 80% of dogs observed unleashed in the Snowy Plover Protection Area. In contrast, many fewer dogs?mostly on leash?were observed in the Wildlife Protection Area at Crissy Field, where the area is smaller and where National Park Service (NPS) staff installed protective fencing, entrance gates, and signage in 2010. Dog owners were often observed approaching Crissy Field?s fenced Wildlife Protection Area but turning back at the fence without entering. Continued low levels of compliance with leash regulations at Ocean Beach indicate a need to enhance outreach and enforcement actions related to off-leash dog walking.