Meet The Locals: Western Fence Lizards, or Bluebellies

Sceloporus occidentalis

For many native species, habitat loss, overconsumption, disease, and out-competition by invasive species have been the customary tragedies of the modern human era. The world of industry through capitalism has meant that many species' lives, homes, and histories have been upended by Western expansion across the globe. And yet, this is not always the case for all creatures. Some, despite the ever-changing world around them, may shift with the world, and not just survive, but thrive. In California there is no better example than the Western fence lizard.

At times called bluebellies for their distinctive undersides which brighten marvelously on males during the spring breeding season, these small lizards are nearly omnipresent across the state, in any semi-arid region. Walking on a trail, or passing through a manicured garden, you’ll often spot them only for a second before they dash away from fence lines or duck into the shade of a leaf or rock. Like their name suggests, they do love to sit atop the wooden fences on trails and range-lands to bask in the sun and look over their territory for other lizards. If they spot another bluebelly, they will sometimes do push-ups, which scientists believe is a form of communication meant to defend their territory without fighting directly. 

While their ubiquity makes us fail to consider our neighbor, their presence might be a great aid to those of us who enjoy going out into the open, grassy California hills and meadows. In recent years, scientists have discovered that fence lizards might be inadvertently helping keep lyme disease down within the state. Ticks, the quiet menace that slowly wreak havoc on one's life, often also feed on the blood of bluebellies. Scientists discovered that there is a protein in their blood that kills the bacteria that causes lyme disease in ticks. The ticks will latch onto the lizard, feasting on their blood, and their blood in turn will essentially cleanse the tick of the bacteria that causes lyme disease. This then means that there are often less lyme-ridden ticks in areas where they live in the American West, causing scientists to wonder if this is the main reason why lyme disease has not spread across the West as easily as it has in many other areas of the county. 

Greg Sarris, Chairman of the Federated Indians of Graton Rancheria in Sonoma and Marin County, wrote in Bay Nature in 2011, that the bluebellies are a reminder of the return to spring, “According to the old stories, the sun gave Bluebelly a piece of its home — the sky — to wear as a sign of kinship. Sun said to Bluebelly, ‘With my home on your stomach, the people will always know to remember me. When they see you each spring, again sitting atop the rocks, they will know too that I have returned. Your belly will match the sky where once again I’m looking down.’” 

Next time you're out on a walk, even around the rocks on the west side of Lake Merritt, and you spot a fence lizard, don’t forget that they have been here far longer than us. They know to live with the sun, and they will always thrive here, in ever shifting, sun-soaked land.