There are typically 8 main reasons attributed for the overall decline in the monarch butterfly population.
1. Pathogens and Diseases
2. Destruction of habitat (We lose 6,000 acres of potential monarch/pollinator habitat a day in the United Stated due to development or 2.2 million acres per year).
3. Lack of floral food for migrating adults
4. Loss of Milkweed plants
5. Increased use of herbicides
6. Pesticides
7. Natural Enemies (such as the cobalt milkweed beetle and red-femured milkweed beetle)
8. Weather changes
Sources:
“Downtown Salt Lake City.” Wikipedia, Wikimedia Foundation, 29 Dec. 2021, https://en.wikipedia.org/wiki/Downtown_Salt_Lake_City.
“Multiple Ways of Saving the Monarchs.” Monarch Butterfly Habitat Corridor, Gardens, and Other Strategies to Protect Native Milkweed Plants Can Prevent Monarch Butterfly Extinction., https://www.monarch-butterfly.com/saving-monarchs.html.
“Utah Pest News.” ANY.RUN - Free Malware Sandbox Online, https://any.run/report/4a6a95966894eb824b41d56e6d680aee86bec00f0e19fb02b09d5757adebb2ab/46b01e24-6653-49c7-8ab6-a45dfd06b675.
Belsky, Joseph, and Neelendra K. Joshi. “Assessing Role of Major Drivers in Recent Decline of Monarch Butterfly Population in North America.” Frontiers, Frontiers, 1 Jan. 1AD, https://www.frontiersin.org/articles/10.3389/fenvs.2018.00086/full.
1. Pathogens and Diseases
2. Destruction of habitat (We lose 6,000 acres of potential monarch/pollinator habitat a day in the United Stated due to development or 2.2 million acres per year).
3. Lack of floral food for migrating adults
4. Loss of Milkweed plants
5. Increased use of herbicides
6. Pesticides
7. Natural Enemies (such as the cobalt milkweed beetle and red-femured milkweed beetle)
8. Weather changes
Sources:
“Downtown Salt Lake City.” Wikipedia, Wikimedia Foundation, 29 Dec. 2021, https://en.wikipedia.org/wiki/Downtown_Salt_Lake_City.
“Multiple Ways of Saving the Monarchs.” Monarch Butterfly Habitat Corridor, Gardens, and Other Strategies to Protect Native Milkweed Plants Can Prevent Monarch Butterfly Extinction., https://www.monarch-butterfly.com/saving-monarchs.html.
“Utah Pest News.” ANY.RUN - Free Malware Sandbox Online, https://any.run/report/4a6a95966894eb824b41d56e6d680aee86bec00f0e19fb02b09d5757adebb2ab/46b01e24-6653-49c7-8ab6-a45dfd06b675.
Belsky, Joseph, and Neelendra K. Joshi. “Assessing Role of Major Drivers in Recent Decline of Monarch Butterfly Population in North America.” Frontiers, Frontiers, 1 Jan. 1AD, https://www.frontiersin.org/articles/10.3389/fenvs.2018.00086/full.