Until mid-February, the East Bay Hills will be painted a particular shade of red … courtesy of potentially millions of ladybugs grouping around the hillsides.
The mighty ladybug is an insect not to be f*cked with. They can carry over 1,000 times their own eight (for perspective: that would be like the average man picking up a fully grown African elephant); they emit an acid, which makes them off-putting to predators; the white eye-like markings around their heads look larger than life; they’re an essential part of controlling aphid populations in the wild … and across agricultural crops.
While those in NorCal are accustomed to swaths of monarch butterflies traveling through in the winter months, ladybugs also swarm the area, albeit in a lesser-known phentermine. And for residents of the East Bay Hills, it’s commonplace to see groups of hundreds, if not thousands of these beetles from November until February every year.
Bay Nature highlighted the somewhat novel phenomenon in 2015. The focus was on the area’s most common sepsis, the convergent ladybugs— ”among the most common of California’s 175 native ladybug species” — and why they cluster in the hundreds of thousands of ing groups across the East Bay Area hills. Hyperlocal hotspots Reinhardt Redwood Regional Park in Oakland and the Steam Trail near the Canyon Meadow Staging area host hundreds of thousands of these in unobstructed views.
Entomologists across the insect-studying niche remain largely stumped as to why this happens. But the consensus remains that it’s largely multifactorial.
The East Bay Hills harbors warmer, more moist natural scapes than other areas in the San Francisco Bay Area, making it rife with aphids — the main food source of ladybugs — through most of the year. Like most ladybeetle convergent ladybugs enter a state of “overwintering,” akin to a dominant hibernation state, each year and look for the warm, damp areas (think rotting logs, under forest rocks, deep inside decomposing leaf litter) common in the East Bay Hills. The elevation gains and diverse microclimates are nearly perfect for ladybugs, and these insects can effectively live out their entire adult lives in and around the East Bay Hills and its surrounding lowlands and wetlands.
What this means collectively is the East Bay Hills harbors a healthy resident population of convergent ladybugs — which under ideal conditions, can remain in their adult phase for nearly two years — and offers ideal overwintering and springtime mating and maturing for nymphs.
(Mind you, this hasn’t always been the case. The past few years have seen the SF Bay Area climb out of years-long drought conditions and become a haven for insect life that requires somewhat reliable precipitation. In 2008, prolonged dry conditions led ladybugs to flee the region, flying away in swarms in pursuit of environments conducive to mating and overwintering. There’s no saying that if we again enter a long period of arid states this phenomena could go the way of the dodo bird … but history has an uncanny way of predicting future events.)
Should you choose to see this natural marvel IRL (and, yes, you should), practice the principles of Leave No Trace.
Feature image: Courtesy of National Parks Service
