Monarch butterfly populations decline by 86 percent in a year

The transcript discusses the significant decline in monarch butterfly populations in California, highlighting a drop from 148,000 in 2017 to 20,456 in a year. Research indicates a 72% risk of extinction in 20 years due to factors like habitat loss, pesticide use, and climate change. Rising carbon dioxide levels may contaminate milkweed, the monarch caterpillar's sole food source, while increasing temperatures could alter migration routes and affect breeding areas.

What was the population of overwintering monarch butterflies in California in 2017?

• 148,000

• 20,456

• 200,000

• 72,000

What is the estimated risk of monarch butterflies becoming extinct in 20 years?

• 72%

• 60%

• 50%

• 80%

Which of the following is NOT a factor contributing to the decline in monarch butterfly populations?

• Pesticide use

• Climate change

• Habitat loss

• Increased predation

What plant is the sole food source for monarch caterpillars?

• Rose

• Dandelion

• Milkweed

• Sunflower

How might increasing temperatures affect monarch butterflies?

• Change their color

• Increase their size

• Alter their migration route

• Shorten their lifespan