Pollinator week is here (June 16 – 22), the Summer Solstice arrives this Saturday and Dr. Chip Taylor of Monarch Watch is bullish on Monarchs this season.
Taylor has been updating the DPLEX list of late with positive, upbeat messages suggesting that this year’s Monarch crop may be slightly larger than last year’s record low. That would be heartening.
Skippers and other pollinators enjoyed the Swamp milkweed last weekend on the Llano. No Monarchs. Yet. Photo by Monika Maeckle
“There will be a modest increase in Monarch numbers and most of that will come from the upper midwest,” Dr. Taylor wrote via email when asked to explain.
For those unaware, the D-PLEX list, named after the Monarch butterfly’s Latin designation, Danaus plexipus, is an old-fashioned email listserv started by Taylor that reaches hundreds of butterfly enthusiasts and scientists. Sign up to receive D-PLEX emails on the Monarch Watch webpage.
Taylor bases his predictions on past history, warmer temperatures this spring and a late summer. Also, this year’s tough winter has obliterated the usual natural predators to
Tachinid flies lay their eggs on Monarch caterpillars, using them as a host. Taylor says they are not as pervasive this year as in years past. Photo via University of Georgia Athens
Monarch larvae–the tachinid flies, wasps, spiders and other death threats that couple with climate change, habitat loss, genetically modified crops and insecticide use to pose a grave threat to the continuation of the Monarch butterfly migration.
Here’s what Dr. Taylor wrote on June 15:
The harsh winter may account in part for the lack of predators but the last three dry summers may have driven local predator populations down as well…. The tachinid flies also seem to be down….
Whatever the cause, or causes, of these low numbers of predators and parasites, Monarch larvae should survive in greater numbers. Elevated reproductive success in early generations usually leads to growth of the population.
We’ll take it.
The Solstice occurs this Saturday, June 21 at 5:51 AM CDT marking the astronomical moment when the sun reaches its northernmost point in the sky, resulting in the longest day of the year. From here til December, the days will get shorter. Monarch butterflies use the sun compass in their antennae to pick up on these solar cues and by late August they’ll start heading south on their journey to Mexico to roost for the winter. Won’t be long now.
Keep an eye out for those that respond to the sun’s signals and your fingers crossed that Dr. Taylor’s optimistic predictions are correct.
Like what you’re reading? Follow butterfly and native plant news at the Texas Butterfly Ranch. Sign up for email delivery, like us on Facebook, or follow us on Twitter, @monikam.