February 16, 2016
Valentine’s Day came early this year for these amorous Convergent ladybugs. Photo credit: Lila Higgins. Last weekend on a hike to Sandstone Peak, the highest point in the Santa Monica mountains, fellow bug enthusiast Lila Higgins came across a brazen beetle Bacchanalia in full midday swing. Hundreds of ladybugs had gathered on a rotting log where they had previously been “chilling out” for several months. Hippodamia convergens, known as the Convergent ladybug, exhibits this adaptive behavior; these ladybugs will migrate in the fall to higher elevations to overwinter in large aggregations consisting of thousands of individuals. Just as the unseasonably sunny weather inspired Lila to go for a hike, the ladybugs awoke from their rest feeling frisky and ready for action. Gentlemen and lady ladybugs paired off for a little afternoon delight, after which they prepared to migrate back down the mountain to lay eggs and find food. Both the adults and immature larvae are predators, feeding on soft-bodied insects such as aphids and mealybugs. If you have ever purchased ladybugs from a store to use as a natural form a pest control, then you have first hand experience with the Convergent ladybug. California’s Sierra Nevada mountains boasts impressively large aggregations of overwintering Convergent ladybugs, where they are collected by the thousands for commercial use. Many entomologists do not endorse the practice of releasing these store bought ladybugs into your yard for natural pest management because of its questionable efficacy. As mentioned above, Convergent ladybugs migrate as soon as they warm up, so the majority of the chilled ladybugs released in your yard will instinctively fly away. This is not to say that ladybugs are not important as natural predators- they most certainly are! We have several hundred species of ladybugs in California that are already out on the prowl, looking for juicy bugs to eat. As long as we keep our yards a bug friendly zone, our local insect predators will come ahuntin’!
Just a sample of the L.A. ladybug diversity that we have recorded as part of the BioSCAN project. Photo credit: Kelsey Bailey. Ladybugs, along with butterflies and praying mantids, are one of the most beloved insects groups. I have read dozens of poems celebrating the life of the ladybug, but my favorite of all are these wonderful limericks written by an entomologist of many talents, Emily Hartop. Please enjoy! The Ladybug A lady, a bug, dressed in spots A red coat with the blackest of dots So shiny and round She makes not a sound As dainty, along stem, she trots But surprise is lurking within For the dainty she is a him! And she isn’t so lovely The aphids are unlucky To make an encounter so grim For this ‘lady’ she really is gruesome Her and her larvae a terrible twosome Both predaceous and fierce Their prey they do pierce Where did the “lady” name come from? So I warn the ladybug lover Do not judge a book by its cover We may love this bug But he’s just a thug A hoodlum undercover!