Just off Highway 1 lies one of the best places to see the iconic monarch butterfly around. The Pismo Monarch Grove is a dedicated area filled with towering Eucalyptus trees which the monarchs use as refuge during their grand migrations. Even just approaching the area, you’ll notice a marked increase in the amount of butterflies in the location. Oftentimes, they’ll be fluttering around the heights of the trees or resting in the open grass to warm their wings. The tranquility of the grove offers a lovely place to relax and sit while you watch these marvelous insects. Another peculiar thing one might note is the number of spinning apparatuses located in the treetops. These instruments measure wind speed to be used alongside the monarch counts. This data is crucial to understanding how best to preserve this irreplaceable sanctuary for monarchs.
But why exactly do the monarchs cluster here together every winter? Despite being such a colorful insect, the monarch butterfly can be found as far north as Canada. A part of their strategy to survival is finding locations with just the correct temperature during the winter months. Not too cold that it would kill them, but cool enough that their metabolisms are slowed meaning that their lives are extended. And they will travel many miles, sometimes around 2,000 or so, just to make these grand exoduses. The Pismo State Beach Monarch Grove is just one of around four hundred overwinter locations in the state, and one of the most important among them due to the high number of monarchs that overwinter here annually.
Here’s where it gets even crazier. The typical lifespan of a monarch butterfly is roughly 2-6 weeks. With such a short lifespan, why would they spend precious time overwintering in this location? Well, there’s a special exception to this rule as the last generation of monarchs born during the last months of the year are special in that they undergo reproductive diapause, a kind of state which prevents them from reproducing. This is contrary to monarchs born in earlier months which are sexually mature the moment they emerge from the chrysalis. When spring arrives however, they are then able to reproduce and the next generation of monarchs will be born. Interestingly, the locations these monarchs seek out on their grand journeys are locations they have never been to before. It may have been generations even after the original departure before the new generation reaches its location.
The sight of trees bathed in orange and black is certainly one to add to your bucket list. This behavior is called clustering and it also helps them survive the colder temperatures of winter. Because of this, the best time to see this behavior is during the fall and winter months of October to February when it’s too cold for them to be flying that frequently. If the time is just right, and you’re in the area, be sure you don’t miss out on witnessing one of nature’s most fascinating phenomena of intergenerational migrating behavior. They may seem fragile, but these are some of the toughest insects out there.