A breathtaking Blitz!

André-Philippe Drapeau Picard: Thursday, August 17, 2017

By Daphné Laurier Montpetit
Mission Monarch coordinator

From July 29th to August 6th was held the second Mission Monarch Blitz. This year again, the participation (of the citizens and monarchs!) exceeded the expectations. Here is a summary of the week, in numbers.


During the nine days of the Blitz, 115 participants submitted more than 249 missions, exceeding in one week the total number of missions of the 2016 season!
A mission is any outing during which one or more milkweed plants are examined in search of monarch caterpillars and for which observations are shared on the website. People from several Canadian provinces (and even some American states) carried out these 249 missions.


Is the number of milkweed plants inspected by our citizen scientists during the week. This is excellent news, since the host plant of the monarch is at the heart of the mission. The research behind Mission Monarch focuses on identifying the best breeding habitats of the monarch butterfly, and milkweed is an essential part of it. In short, it is as important to document the host plant as the presence of the butterfly. The data collected on milkweed are therefore very valuable, even if no monarchs are found.


Experts agree: we are, so far, witnessing a better year for monarchs. Monarchs observations are on the rise throughout its breeding range, and the 606 adult monarchs reported during the Blitz are only supporting the trend.

The size of populations of migratory monarchs is calculated by counting the number of hectares they occupy during their overwintering season. Based on this summer’s assessment so far, we are hopeful that this year’s count will meet the 2010 and 2015 numbers. Back then, the eastern population covered just over 4 hectares. Still below the last 25 years avergade of 6 hectares, but compared with the 0.67 hectares occupied in 2013, this is a step in the right direction!


They are the stars we hoped to see, and they were there in numbers! During the Blitz, 223 caterpillars were spotted on milkweed plants inventoried.

Caterpillars provide clues to the quality of summer breeding sites. Where they are (and survive), we know that the conditions are adequate. By listing sightings of monarch caterpillars, a map of the most productive habitats can be identified and prioritized to optimize the conservation efforts of the monarch.

No time to rest for monarchs!

The Blitz is over, but for monarchs, the biggest job is coming! The caterpillars that will be observed over the next few weeks will be those that, once adults, will undertake the long journey to their overwintering areas in Mexico. Let’s enjoy their last days among us! The missions carried out in the late summer are just as useful as those during the Blitz.

So, dear participants, we count on you to get back out there and look for caterpillars!
Good missions!