Tick Surveillance, Water Year 2024-2025
Tick Collections from parks, 2024-2025 Season (November 2024 through May 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 May include Edgewood Park in Redwood City, San Pedro Valley Park in Pacifica, La Honda Open Space Preserve near La Honda, and Waterdog Lake in Belmont. Surveys of tick nymphs will continue in June.
Tick Collections from parks and neighborhoods, 2024-2025 Season (through May 2025)
| 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 | 235 |
| 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 | 112 |
| Thornewood Open Space | Woodside | 324 | |
| Junipero Serra Park | San Bruno | 20 | |
| Eaton Park | San Carlos | 31 | |
| Los Trancos Open Space | Portola Valley | 315 | 74 |
| San Pedro Valley Park | Pacifica | 80 | |
| La Honda Open Space | La Honda | 6 | 71 |
Page last reviewed June 5, 2025