San Juan Island has ticks; people and dogs have encountered them from Roche Harbor to Cattle Point; from Friday Harbor to the west side; on Cady Mountain and Mount Young. Since 2021, researchers at the conservation biology laboratory Kwiaht have identified and tested nearly two hundred ticks found by islanders. A little more than one in ten ticks were infected with at least one that can cause severe illness in people as well as their pets.
Black-legged tick from San Juan Island
At the top of the list is Babesia, a microparasite in the blood of ticks that can cause symptoms similar to Lyme Disease. Babesiosis has been flagged by the Centers for Disease Control as a significant emerging public health concern in the eastern United States, where it is now widespread. Small numbers of cases have begun to be diagnosed on the Pacific Coast, where they have been linked to different species of Babesia and is presumably still adapting to new conditions and new non-human hosts in the environment.
The key to protecting people (and their pets) from Babesiosis in the islands is discovering where, in our island ecosystems, the ticks that carry Babesia are feeding and reproducing. Each ticks must go through three life-history stages before it can reproduce, and each stage involves a blood meal from a different host. For now, the key hosts are hidden somewhere among the islands’ diverse native and introduced wildlife.
Based on the experiences of the eastern states and California, where more research has already been done, key hosts could include both mammals and reptiles. They could include mice, voles, rabbits, squirrel, foxes, and deer. Birds are not entirely out of the question, although less likely to support large local tick populations. Finding the local hosts in the islands is an important step in controlling the spread of ticks and the diseases they can transmit through a bite.
In cooperation with the Washington Department of Health and the Washington Department of Fish and Wildlife, Kwiaht researchers have begun trapping “candidate species” on San Juan Island, checking them for ticks, and testing ticks and their wild hosts for Babesia and other pathogens.
Wildlife brought to Wolf Hollow Wildlife Rehabilitation Center for care, or trapped by WDFW biologists for other studies, are also being examined for ticks.
This involves a lot of fieldwork and lab expenses, which have thus far been funded primarily by islanders through the San Juan Island Community Foundation.
You can help; the Community Foundation’s County Fair Giving Campaign this week (through Saturday August 19) is an opportunity to help Kwiaht stop ticks in their tracks by discovering their key wild hosts. Donations can be made online at https://sjicf.org/ or by checks made out to the Community Foundation that have “Kwiaht” written on the memo line.