I get excited when I see one butterfly. Last weekend I joined a guided tour with Natural Bridges State Beach docent Alyse Lui and saw more than 2,000 of them. October marks the arrival of monarch butterflies from the Rocky Mountain range, and Natural Bridges hosts these lepidopterids in all of their delicate glory.
Much like the monarchs before a big migration, the tour starts with the basics: food. Lui, a nature enthusiast in a brown Friends of Santa Cruz State Parks jacket, leads us to a fenced-in 20ft x 20ft rectangle where we find about a dozen types of milkweed. Before their migration, monarchs plump up on milkweed and nectar, storing as much body fat as they can for the next 2,000 wind-blown miles.
“Milkweed is actually poisonous, but it’s their favorite, and the female monarchs are very picky about where they lay their eggs—it’s milkweed or nothing,” says Lui.
Santa Cruz’s dependable 65-degree fall weather draws the butterflies to the thick canopy of Natural Bridge’s eucalyptus grove—the tour’s main event. From the milkweed garden we amble down a zigzagging wooden walkway, submerging ourselves into the chilly shade of the eucalyptus trees. The walkway winds back and forth through a tranquil scene punctuated with laminated posters of butterfly trivia. About three-quarters of the way down the ramp we’ve yet to see a butterfly. But in the last stretch of the walkway our tour pauses at a telescope angled slightly skyward. All of our eyes naturally trace the telescope’s line of vision, and next to me, a little girl gasps and points. “OH! There they are!” My thoughts exactly.
Thousands are nestled in trees, layered in bushes and fluttering across the sky. Lui urges us to peer through the telescope and “get up close and personal.” Butterflies spill outside of the scope of the lens and layer on top of each other like shingles on a roof. Even in (what I imagine) are uncomfortably close quarters, the clouds of orange and black buzz with energy and motion.
Just beyond the telescope is an expansive wooden platform directly below the bulk of the monarchs. This is where most spectators collect. Families with young children tend to visit the butterflies, making for a fairly dependable kid-gets-excited followed by mom-shushes-kid pattern. Please everyone, use your “butterfly voices.”
Third graders on field trips, locals and tourists all quietly congregate alongside the families and marvel at the sights in the pit of the grove. Not many crowds of people are this peaceful. It’s hard to be stressed when you’re surrounded by 2,000 butterflies (something I’ll keep in mind for finals week).
In past years, Lui explains, the monarch count exceeded 4,000, but numbers have dwindled considerably. Natural Bridges’ naturalists speculate that the overall decrease in monarchs stems from ebbing milkweed growth and excessive pesticide usage. But by no means have butterfly lovers lost hope. Planting milkweed, especially in the Bay Area, has shown promising rebound potential for the monarchs.
At Natural Bridges, numbers fell during a period of violent winds in the 1990s. It’s not that the butterflies were helplessly blown away; it’s that the eucalyptus trees were losing limbs from the intense gusts.
Monterey pine trees used to expand across most of Natural Bridges, providing the eucalyptus grove with protection from blustery winds. But when pitch canker—a pine tree-killing disease—infected the vast majority of pines they had to be removed, leaving the eucalyptus grove vulnerable. Large monarch-attracting branches were torn off and a small number of eucalyptus trees were blown over. Cypress trees were planted as a new source of wind protection and have proven to be a sturdy shield, allowing some monarchs to retain their temporary home at Natural Bridges.
Though this year’s count is only around half as much as previous years, the thick of the season hasn’t hit yet. Butterflies typically stay at Natural Bridges until late January, but peak in mid-November.
Heading back up the wooden walkway, a small child passes me and grins. “I just saw one!” he exclaims. I smile and congratulate him. He’s in for a real treat.
