This summer’s drought and record heat could affect the autumn migration of the monarch butterfly in danger of extinction, according to researchers at the University of Ottawa.
They say that the extreme climate can be prohibiting plants to produce enough nectar that monarchs need to feed their autumn migration to Mexico.
“We believe that climate change is the key factor. More and more, it has actually been prioritized as the main threat of face the monarchs, especially since 2005,” said associated professor Heather Kharouba.
“We know, especially watching the numbers we get from Mexico, that if there was a year of bad weather, it really affects the monarchs.”
The monarch is a kind of popular butterfly that lives in all the provinces of Canada with the exception of Newfoundland and Labrador, according to the profile of the Government of the Canada government.
Climate change and the Canadian environment have classified the butterfly as in danger since December 2023 under the Federal Law of Species at risk.
The agency associated with the University and Kharouba to investigate how the plants they need are affected by warming temperatures.
In a farm in Kinburn on the western rural edge of Ottawa, the Kharouba team has placed approximately 40 cages in pairs of around five different species of plants.
One of each pair contains a mini-greenhouse of open ceiling around the plant, increasing the temperature in a few degrees to imitate the effects of climate change.
“It is really important to know how flowers change, so if they bloom before or if they flourish later, that has important implications for the population,” said Jenna Boomhower, a master’s student at the University of Ottawa who leads the project under the supervision of Kharouba.
Boomhower said that during one of this year’s heat waves, temperatures in the mini Greenhouse increased to 50 ° C, compared to the control cage in around 45 C.
Throughout the summer, the monarchs are placed in the cage noted where they can feed on the nectar from the plant, Boomhower explained.
Then, the researchers weigh the monarch for a period of five days and measure the amount of sugar on the plant using portable instruments and capillary tubes to determine the quality of the nectar.
According to Boomhower, providing good quality nectar should allow the monarch to increase weight and build energy reserves.
While the researchers initially focused on the impact of heating temperatures on plants, this non -anticipated dry summer has added an additional layer of complexity.
“The drought has caused the nectar to be thicker, and that can create problems for the monarchs while trying to get the nectar with their trunk,” Boomhower said. “Have you ever tried to drink a shake with a small straw? It’s really difficult to go out.”
The lack of moisture also created problems for plants, many of which dried and died.
“It is completely killed to some of the plants we have been considering. So, in that sense, there is no food from those available plants, there are no flowers,” Kharouba said.
“At this time we are looking to see how the monarchs will respond to the flowers that have been under these drought conditions.”
The experiment extends until September 15, when researchers will begin a detailed analysis of their findings.
While Kharouba’s team took five butterflies from the field, raised more than 300 monarchs, many of which will be more thoroughly analyzed. The rest of the butterflies will be released for migration.
