Garrapata (Spanish for tick) State Park in Big Sur.
(Courtesy Daniel J. Salkeld)
Environment

Ticked-off scientists: Santa Cruzans need not worry about blood-sucking arachnids crawling our beaches

The scientist behind a recent study that found ticks — some carrying Lyme disease — in California’s “coastal areas” would like to set some things straight. For starters, ticks do not hang out in the sand.

Many Santa Cruz County residents and Lookout readers were alarmed by the results of a new study that found that ticks, some of them carrying Lyme disease, are prevalent in California coastal areas. The news conjured images of ticks crawling the sand and latching on to sunbathers.

Lyme disease-carrying ticks usually found in woodlands and fields are spreading along California’s beaches, carried by...

Daniel Salkeld, an ecologist and the lead author of that study, says the facts of what he found are much less alarming.

“These are not like blood-sucking crabs crawling over the sand,” Salkeld said. “[The ticks are] on those areas of scrubs that you might walk through to get down to the beach, like those trails that are following the clifftops that have coastal chaparral or grasslands.”

The news that ticks are present in coastal chaparral is likely not a surprise to most Santa Cruz residents. Ticks along the California coast have been a fact of life for decades — whether wandering down the trails of beaches north of Santa Cruz or much further south.

Garrapata State Park in Big Sur was established in 1985, and garrapata is Spanish for tick.

So although the presence of ticks in the coastal zone (not on the beach!) was unsurprising, the fact that some of these ticks were infected with Lyme disease and a related bacterium, Borrelia miyamotoi, was unexpected.

“We wouldn’t have expected them to be infected with tick-borne diseases because in those habitats you don’t have Western grey squirrels,” Salkeld said. “Those are what we understand is the main reservoir for Lyme disease in California. So, given the absence of those, I expected the ticks might be there but they wouldn’t be infected with anything.”

The numbers were small and shouldn’t be too alarming, Salkeld said. The highest prevalence of the bacteria the scientists found at any site in Santa Cruz was two out of twenty ticks, which was at Nisene Marks (though Salkeld cautioned this is a small sample size to draw conclusions from). But the question of what animal is hosting the disease remains a mystery. Squirrels are present in the coastal zone, but they’re usually ground squirrels, a different species.

“It’s kind of a humbling realization that we don’t know everything about disease ecology and Lyme disease in California,” Salkeld said. “It could be ground squirrels, it could be voles or rabbits or possibly even birds. That’s anyone’s guess.”

For now, the most important thing for Santa Cruz County residents to know is that tick precautions, including tick checks, are an essential safety measure — whether you’re hiking in the hills or the coastal grasslands.