The Migration Route of the Monarch Butterflies to Mexico is a miraculous journey.
This journey begins around late August in the Northern states and Southern Canada.
The peak of the Monarch migration is mid to late September.....
continuing through October into mid-November.
Although the Monarchs start their journey Southward individually, they start to gather at points along the migration route to rest, feed and drink.
These are called roosting sites.
Avoiding open water, they follow the water's edge, peninsulas and fingers of land. The Monarchs seem to sense bad weather and avoid flight.....which can hold them in one place, increasing their numbers to the 1000's.
My daughter went to college in Newport, Rhode Island and was hiking at Sachuest Wildlife Refuge late last Fall. This is located on a peninsula near Newport. She noticed many butterflies flying around her, when she came upon a tall tree covered with "leaves" which upon closer inspection she realized were Monarch Butterflies!! As she continued along, another tree was also covered with Monarchs. She had discovered a roosting site!
Three factors determine roost location:
Size of trees
They settle on the downward side of trees and close their wings. They use small hooks on their legs to grip the bark or leaves.
If the temperature drops below 50 degrees they enter a state of torpor or semi-paralysis. As the temperature climbs in the morning, the Monarchs warm their wings and continue on their migration route.
They glide at an altitude of 4000 feet from thermal to thermal taking advantage of warm air currents. They fly at about 12 MPH and travel only during the day.
A large number of wildflowers are needed so the Monarchs can store nectar in a part of their body called the lipid mass. This carries them through the long winter. Many die if the wildflowers are not plentiful due to heat or drought.
The Monarch Butterflies that survive continue on their journey to Mexico......What a miracle that the Monarchs seem to know exactly where they are going!!