Tick Surveillance, Water Year 2024-2025
Tick Collections from parks, 2024-2025 Season (November 2024 through April 2025)
Laboratory staff continued field collections of nymphal Ixodes pacificus (Western black-legged ticks) in April. Nymphal ticks are collected by flagging with a white sheet of flannel attached to a wooden dowel, in leaf litter areas or on rocks and fallen logs. Ixodes pacificus ticks will be tested for the presence of Borrelia burgdorferi (the agent of Lyme disease), as well as Borrelia miyamotoi (the agent of hard-tick relapsing fever) and Anaplasma phagocytophilum (the agent of granulocytic anaplasmosis).
Parks surveyed in April include Edgewood Park in Redwood City, Eaton Park in San Carlos, Wunderlich Park in Woodside. Additionally, a school in an unincorporated area near San Mateo and a few residential yards in Portola Valley, San Mateo and Hillsborough were flagged for Ixodes nymphs. Surveys of tick nymphs will continue in May and June.
Tick Collections from parks and neighborhoods, 2024-2025 Season (through April2025)
| Park/Neighborhood | Nearest City/Town | Number of Ix. pacificus adults | Number of Ix. pacificus nymphs |
|---|---|---|---|
| Windy Hill Open Space Preserve | Portola Valley | 412 | |
| Wunderlich Park | Woodside | 379 | 153 |
| Edgewood Park | Redwood City | 854 | 124 |
| Crystal Springs Regional Trail | San Mateo | 113 | |
| Laurelwood Park | San Mateo | 242 | |
| Pulgas Ridge Open Space Preserve | Redwood City | 255 | |
| Wavecrest Open Space | Half Moon Bay | 53 | |
| Mills Canyon | Burlingame | 198 | |
| Sweeney Ridge | Pacifica | 19 | |
| Waterdog Lake | Belmont | 458 | |
| Thornewood Open Space | Woodside | 324 | |
| Junipero Serra Park | San Bruno | 20 | |
| Eaton Park | San Carlos | 31 | |
| Los Trancos Open Space | Portola Valley | 315 | 74 |
Page last reviewed May 13, 2025