Snowy Plover Population Monitoring, Research, and Management Actions: 2008 Nesting Season Research Progress Report
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Snowy Plover Population Monitoring, Research, and Management Actions: 2007 Nesting Season Research Progress Report

Snowy Plover Distribution, Abundance & Reproductive Success: 2006 Research Progress Report

Snowy Plover Population Monitoring, Research, and Management Actions:
2008 Nesting Season Research Progress Report
Scott F. Pearson, Cyndie Sundstrom, Kathryn Gunther, Deborah Jaques, and Kirsten Brennan
March 2009

Breeding Phenology

• Clutches were initiated between 24 March and 15 July. However, very early nests could have gone undetected because intensive surveys did not start until after April 1
• The first chick to fledge, fledged around 8 June and the last chick known to fledge, fledged around 3 September.

Breeding Range

• Conducted 39 surveys on 12 sites to either assess occupancy or to count the number of nesting adults
• Snowy Plovers nested on Leadbetter, Midway Beach, and Graveyard Spit. Plovers did not nest on Damon Point or surrounding areas and there was no evidence of plover presence on other areas surveyed.
• To determine site occupancy, we continue to recommend conducting three surveys of a potential nesting site by experienced observers between early to mid-May and the end of the first week of July – the period of greatest plover nesting activity – to have a very high probability of determining site occupancy.

Number of Breeding Adults

• The mean 2008 Washington breeding adult population was 55 (95% Confidence interval: 42-68). Nearly all of the breeding adults were found on Leadbetter Point and Midway/Grayland Beach. Staff and volunteer surveyors conducted surveys with volunteers contributing approximately 306 hours.
• Errors associated with double counting and detectability were addressed.

Nesting Success

• Fifty-six nests were discovered and monitored.
• The percent of nests that survived from egg laying through hatching during the 2008 nesting season was 36% which was almost identical to the 2007 nesting season.
• As in past years, the primary sources of nest failure were predation (primarily by crows and ravens but also coyotes) and nests buried by drifting sand. A number of nests were abandoned and two nests were destroyed by humans.

Management Actions

• Education: State Park rangers contacted hundreds of visitors and their enforcement and patrol activities emphasizeeducation and not citation. Washington Department of Fish and Wildlife presented one program on Snowy Plovers to approximately 10 Audubon volunteers in the spring of 2008.
• Enforcement: State Parks Beach Rangers patrolled nesting habitat in the Grayland Beach State Park vicinity (Midway/Grayland Beach) and Cape Disappointment State Park (Leadbetter Point). Seven State Park Rangers contacted approximately 33 people on foot, 8 people in vehicles and 3 people on horses within the closed nesting area at Grayland Beach State Park. Contacts emphasized education and no citations were issued. In 2008 there were 10 razor clam digs at Leadbetter and 15 at Midway/Grayland beach and the digs occurred on beaches where Snowy Plovers were actively nesting. State Parks Rangers spent approximately 20 hours during clam tides at Leadbetter point to protect plovers when they made approximately 100 educational contacts. US Fish and Wildlife Service had one or 2 officers work most clam digs for approximately 100 officer hours worked and focused their efforts on keeping people out of the restricted nesting habitat. To accomplish this, they contacted and educated approximately 45 people, they issued warnings to another 49 people, and they issued violation notices (citations) to 19 people. Another 9 people were observed within the closed nesting area, but were gone before officers could get to them. Wildlife Biologist Cyndie Sundstrom worked three clam tides in April and four in May to discourage entry into restricted areas. Technician John Deibert worked with Cyndie during the May 24th clam tide. A Federal agent also followed-up on the apparent removal of eggs from a Snowy Plover nest by people but no arrests or citations occurred because of lack of evidence and authority.
• Restrictions: Beaches were closed to fireworks at locations where State Parks and U.S. Fish and Wildlife Service are the upland land owners.
• Nest exclosures: 28 nests were exclosed on the Wildlife Refuge at Leadbetter, and 9 nests were exclosed on State Park land at Midway Beach.
• Signing: Approximately 7.5 miles of beach was signed at Leadbetter and approximately 1 mile of Midway Beach was signed to restrict human access to the dry portion of the beach and protect nests. Access restrictions did not occur on private land.
• Restoration: U.S. Fish and Wildlife Service cleared approximately 37 acres at Leadbetter dominated by non-native beachgrasses, bringing the total acres treated at this restoration site to 121. Two hundred and sixty-nine cubic yards of oyster shell were added to 3.9 acres. Additional treatments included mechanical clearing of beach grass in January, February and early March, and the herbicide, Imazapyr (brand name: Polaris AQ), was applied by hand (backpack spray) to beachgrass in September to the portion of the HRA containing pink sand verbena plants. Beachgrass near individual pink sand verbena plants was pulled in order to avoid accidently spraying the verbena plants. A tractor-mounted spray boom was used in October to apply chemical to the remainder of the previously cleared area. Herbicide was also applied from a helicopter to a 40 acre area of dense beachgrass on the foredune and outer beach in September.
• In 2007, Washington Department of Fish and Wildlife and State Parks established five treatment plots on Leadbetter State Park (approximately 1 acre each) and five control plots to evaluate the effectiveness of restoration activities for both native plants, Snowy Plovers and Streaked Horned Larks. Pre-treatment bird and plant monitoring was conducted by Washington Department of Fish and Wildlife under the supervision of Dave Hays with the assistance of Audubon volunteers and initial treatments to control non-native beachgrasses were conducted by Washington Department of Fish and Wildlife. Pre-treatment vegetation data were collected in summer 2007 followed by an initial treatment in October 2007 and a second treatment in Sept - Oct 2008. Treatment plots were sprayed with a combination of Polaris AQ (4 pints/acre) and Aquaneat (4.5 pints/acre) each year. The surfactant used was crop oil applied at 1% solution. Each year native plants were covered to prevent direct herbicide application. To remove thatch and to create an open habitat, dead grass was raked in February/March 2008. Another raking is planned for February 2009. Post-treatment vegetation data will be collected in the summer 2009 and an additional treatment is planned for the fall of 2009. The first year of post-treatment bird monitoring occurred in the spring/summer of 2008 with the help of Willapa Hills and Grays Harbor Audubon volunteers and volunteers from the Shoalwater Bird Club who contributed approximately 280 hours to both bird and vegetation monitoring.

Recommendations

• Continue testing methods for estimating adult population size.
• Continue to engage volunteers in monitoring.
• Conduct research to identify the conditions where plover populations can be self sustaining.
• Conduct research to identify habitat features important to successful plover nesting.
• Initiate a study to examine the effectiveness of predator control.
• Continue to link management activities with research and monitoring.
• Evaluate effectiveness and continued use of nest exclosures.
• Evaluate effectiveness and need for habitat restoration areas.
• Evaluate impact and timing of clam digging on plover nesting, foraging and fledging.
• Evaluate effectiveness of enforcement activities on reducing human impacts to plovers.
• Initiate education and outreach activities.