Many people visit Crossroads at Big Creek this time of year to exercise. In some cases, walkers and joggers are hoping to lose weight or to keep that nasty body fat from accumulating. At the sane time, in the upland areas of the preserve, yellow, green and black caterpillars are hatching, eating and metamorphosing into monarch butterflies, and these insects use the meadows of Crossroads to get a fat as possible.
The monarchs we are seeing this time of year soon will begin to migrate to the southern states and Mexico. They are capable of flying as many as 2000 miles.
During migration, monarchs travel an average 80 miles a day. When they reach their winter range, butterflies weigh five times more than when they started. When monarch expert Dr. Lincoln Brower was at Crossroads last spring, he referred to fall monarchs as “little butterballs.”
First, understand that monarchs don't use much energy. Because they are light, they can ride weather patterns. They just flutter into the wind and let it carry them miles and miles, often across several states. Sometimes the wind blows them off course, but it still is the most efficient way to travel.
Another butterfly flight technique is similar to the migration style of hawks. Monarch butterflies merely extend their wings and ride thermals--rising warm air-- high into the sky. Similarly, monarchs ride the up-drafts which form along hills and ridges. After they have reached a great altitude, monarchs just glide down. They can travel many miles without a single flap of the wings.
The travel route of the monarchs is flowery, and that's no coincidence. The butterflies reach an area at just the time vast fields of nectar-rich blossoms are at their peak. And butterflies fuel up with nectar every chance they get. While they travel, monarchs take in more calories than they burn off. The food stored in their bodies will keep them alive as they rest through the winter. In fact, they use so little food during their semi-hibernation that they still have energy reserves to fly north in the spring.
We know that monarchs from Crossroads reach Mexico because, several years ago, the Northeast Wisconsin Audubon (NEW Audubon) offered a workshop on tagging butterflies, and one of the tagged specimens was recovered in the wintering site.
On Monday, September 3 (Labor Day), NEW Audubon repeat this fascinating workshop. Randy Korb will present a program in the Collins Learning Center from 1:00 to 3:00 pm. Following a short presentation on the monarch butterfly and a demonstration of the tagging process, participants will drive to local fields to net monarchs and attach numbered tags to their wings as part of a nationwide project sponsored by the University of Kansas .
This field trip is suitable for children 4years and up. Children should wear long pants. The program is free to NEW Audubon members. The non-member fee is $5 per adult and $3 per child 17 years and under. Pre-registration is not required. Non-members may join NEW Audubon at the event. Butterfly nets are available.
Actually, butterfly nets are available for families any time the Collins Learning Center is open. We encourage families to enjoy capture/ release insect study in our meadows. Or, you could participate in a naturalist-led program. This week, programs about water, beavers and butterflies are offered for families . In honor of Labor Day, we will present videos about historical labor in Door County. Visitors are also invited to attend the meeting of the Door Peninsula Astronomical Society.
The Collins Learning Center is open 11:00-3:00 Monday through Saturday and 1:00-3:00 on Sunday. The Historical Village at the Crossroads is open Saturday and Sunday 1:00-3:00. The trails are always open to the public. Crossroads is located at 2041 Michigan Street (County TT) in Sturgeon Bay.
