Washington State Snowy Plover Population Monitoring, Research, and Management: 2014 Nesting Season Research Progress Report

During the 2014 Western Snowy Plover (Charadrius nivosus nivosus) nesting season, we monitored breeding phenology, nest success, fledging success and number of nesting adult Snowy Plovers in Washington. Field monitoring and research was conducted by Cyndie Sundstrom, William Ritchie, Jennifer Hahn, and Stephanie Doorly with assistance from Brock Hoenes, Warren Michaelis, Steve Spencer, and Larissa Pfleeger. Management activities included restricting human access to nesting sites, predator management, and restoring nesting habitat. A summary of some of our 2014 activities and results:

Breeding Phenology 

• Clutches were initiated between 14 April and 17 July (Figure 2). However, very early nests could have gone undetected because intensive surveys did not start until early April.
• The first chick known to have fledged, fledged around 16 June and the last chick known to fledge, fledged around 11 September.

Breeding Range 

• We conducted 25 surveys at 11 sites between 19 May and 21 August 2014 to either assess site occupancy status or to count the number of adults.
• Snowy Plovers were only found nesting on Leadbetter Point, Midway Beach, and Graveyard Spit.

Number of Breeding Adults 

• The mean 2014 Washington breeding adult population was 41 (Range: 40-43). All of the breeding adults observed were found on Leadbetter Point, Midway Beach, and Graveyard Spit.
• From 2006-2009 the Washington Snowy Plover population declined annually and precipitously. From 2009-2012, the adult breeding population was fairly stable, around 31-36 birds. There is some suggestion of an increase in 2013 and 2014 relative to the recent lows but several more years of monitoring will be needed to assess whether or not trends are indeed changing.

Nest success 

• Forty-seven nests were discovered and monitored at Midway Beach/Graveyard Spit and Leadbetter Point. Based on chicks observed on the beach, we know there were at least 7 additional nests that we did not locate.
• The percent of nests that survived from egg laying through hatching during the 2014 nesting season was approximately 68%. Overall nest success, when accounting for exposure, was 59%. No nests were exclosed in 2014. This is an extremely high nest success rate for unexclosed nests and is likely attributable to USDA Wildlife Service's ongoing predator management on Leadbetter Point and the initiation of predator management at Midway Beach.
• For the second year, nest predation was not the primary source of nest failure. Corvids and coyotes were the only apparent nest predators and were identified based on tracks left at the nest.

Fledging Success 

• The average number of young fledged per adult male on the three Washington nesting sites was 1.88 (possible range = 1.67-2.13). Population viability analyses indicate that, on average, at least one young must fledge per adult male to have a stable population. This fledging rate is the highest that we have ever observed and may again be attributed to predator management.

Management Actions 

• Restrictions: Fireworks were prohibited on beaches where State Parks and U.S. Fish and Wildlife Service (USFWS) are the upland land owners.
• Nest exclosures: No nests were exclosed in 2014.
• Signing: In an effort to protect nests, approximately 8.0 miles of beach at Leadbetter Point and approximately 1.4 miles of beach at Midway Beach were signed to restrict human access on the dry portions of the beach. Access restrictions on private land only occurred when permitted by the land owner. New signs were purchased and now all signs have a similar appearance and message regardless of land ownership.
• Clam tides: Washington Department of Fish and Wildlife and US Fish and Wildlife coordinated law enforcement activities especially during clam tides. A federal fish and wildlife officer helped keep people out of closure areas at Leadbetter Point during clam harvest openings. Portable toilets were again placed on the beach at Leadbetter to minimize intrusions into the closed nesting habitat.
• Nest Predation: Predator management was conducted by wildlife specialists with USDA APHIS Wildlife Services on both Leadbetter Point and Midway/Grayland Beach in 2014. Management consisted of dispersing or targeted lethal removal of known nest predators (corvids) in or adjacent to the plover nesting areas. Early results suggest that this activity was successful in increasing nest hatching rates and fledging rates.
• Restoration: The Willapa NWR habitat restoration area (HRA) at Leadbetter Point now totals more than 400 acres and there is a new 10 acre restoration area on Washington State Parks land at Leadbetter Point. These areas have been mostly cleared of non-native beachgrass using mechanical and chemical methods.