Just a few days ago, our staff was weeding in our trial gardens when they noticed what looked like a leaf hanging under the shed door. Curious, he took a closer look. There, dangling precariously just above the ground, was a tiny green chrysalis. And sure enough, our trials and research coordinator identified it as a monarch butterfly chrysalis. Follow along as ‘Murph’ the monarch completes her metamorphosis and makes her grand entrance.
The distinctive pattern visible on the chrysalis, with the gold stripe at the top and spots towards the bottom, suggested we had a monarch on our hands.
Stage One: Location, Location, Location
Murph began her journey as a single monarch egg, most likely laid on or near our various milkweed plants within the trial gardens. Milkweed, especially Butterfly Milkweed (Asclepias tuberosa), acts as a host plant for the monarch butterfly species as the caterpillars rely solely on milkweed species for food. The adult butterflies will consume nectar from a variety of floral sources.
Monarch caterpillars can travel up to 10 meters from where they hatched, and thus Murph found her spot to pupate and form her chrysalis under a shed door. Upon discovering the chrysalis, we could not ascertain how long the chrysalis had been developing, and as it was in a high-traffic area, we thought it best to move it to a safer location once it was hard enough. The metamorphosis process takes 10 to 14 days, so we agreed to check the next day to ensure the chrysalis would be sturdy enough to transfer.
The Next Day 10:40 AM MST: The chrysalis has lost its green hue and indicates that the monarch butterfly will emerge within 24 hours.
Stage 2: The Beginning
As we discovered the next day, Murph was much farther along in her metamorphosis than we realized. At this point, what was once a caterpillar had secreted digestive enzymes within the chrysalis to break itself down into a nutritious goo. All that was left was the ‘imaginal discs’ that make up the future components of the adult butterfly. The caterpillar was born with these imaginal discs, and as it breaks down, the discs use the protein-rich goo to fuel cells rapidly dividing and growing into adult portions of the monarch, from wings to eyes to legs and more.
By 10:40 AM MST we were far past the “goo” phase and could clearly see the unique monarch wing patterns as the chrysalis became less opaque (pictured right). At this point when the chrysalis has lost its green hue, it’s a safe bet that the butterfly will emerge within 24 hours, so we left Murph safely in place.
1:00 PM MST: The chrysalis has become more transparent as the butterfly pulls itself from the chrysalis walls.
Over the course of the day, the chrysalis rapidly became more transparent. By now, you could clearly see that Murph the caterpillar had been rebuilt into her adult form. Later in the afternoon, you could even see some free air spaces where the body had taken shape and pulled away from the chrysalis wall (pictured left).
Usually, monarchs will eclose (emerge from their chrysalis) in the wee hours of the morning, so we went out at the end of our day with every intention of taking one last photo, and coming back and celebrating a marvelous butterfly birthday the next morning. Much to our surprise, Murph had other plans and her chrysalis broke open just as we were turning to leave!