Unlike recent years, Christina Garcia needed a pen, paper and a fair amount of time Friday to count all the monarch butterflies dangling in clumps high atop the eucalyptus trees at Fremont’s Ardenwood Historic Farm.
Garcia, a naturalist with the East Bay Regional Park District, counted 4,176 butterflies — the most since 1998 and way more than the 224 she counted last year.
“It’s great to see so many of them,” she said. “We thought they were going to keep dropping in numbers and maybe not come at all.”
The butterflies, which spend their winters along the Central and Southern California coast, also can be seen at San Leandro’s Monarch Bay Golf Course and for the first time since 2004, at Point Pinole Regional Shoreline in Richmond.
The Xerces Society, a butterfly conservation group, began the Thanksgiving week butterfly count more than a decade ago to monitor the dramatic decline of monarchs wintering in the state. Counters last year spotted 129,460 butterflies, down from nearly 400,000 a decade earlier.
Garcia said this year’s resurgence might be due to the especially wet spring. Late rain is good for the milkweed plant, which serves both as the monarch’s egg repository and a major food source.
Most monarchs live less than six weeks, first as caterpillars chomping on milkweed and later as butterflies that mate and produce hundreds of eggs.
But the current crop of monarchs lead a very different life.
Instead of rushing to mate, they expend their energy flying at speeds as high as 25 miles per hour to the same select shoreline locales where they’ll live for months before mating in February.
Much of their winter is spent huddled in trees with their wings overlapping like shingles to protect them from wind and rain. But when the sun comes out, they’ll cascade down toward the ground foraging for nectar.
“It’s awesome,” Garcia said. “You can even hear their wings fluttering.”
This is the first year that visitors to Ardenwood are allowed to visit the butterfly grove unattended. The district also runs weekend butterfly walks throughout December and January. The park is located at 34600 Ardenwood Blvd., Fremont. For more information, visit www.ebparks.org/parks/ardenwood or call 510-544-2797.