It all began Friday , September 26, 2014 when the radar at the National Weather Service in St. Louis lit up like a Christmas tree. Since the weather was perfect, the forecasters at the center tried to figure out just what it was that was slowly moving south across their screens. Today the general consensus is that the radar return was from huge clouds of monarch butterflies that were on their annual trek back to Mexico. This radar return prompted an increase in the hopes that the recent decline in the Monarch population may been ending. That may be exactly what has happened according to a recent story on National Public Radio. Although an article in the Washington Post on February 2, 2015 (Click the image to the above left)implied that there appeared to be fewer Monarchs over-wintering in Mexico this year, the NPR story is more recent and comes at the end of the annual Monarch census. To hear the short broadcast click on the "Save the Monarch Butterfly" image above.

 

 

Winter Migration of the Monarch Butterfly and Why this Year is Different

Monarch butterflies are not able to survive the cold winters of most of the United States so they migrate south and west each autumn to escape the cold weather. The monarch migration usually starts in about October of each year, but can start earlier if the weather turns cold sooner than that. The monarch butterflies will spend their winter hibernation in Mexico and some parts of Southern California where it is warm all year long. If the monarch lives in the Eastern states, usually east of the Rocky Mountains, it will migrate to Mexico and hibernate in oyamel fir trees. If the monarch butterfly lives west of the Rocky Mountains, then it will hibernate in and around Pacific Grove, California in eucalyptus trees. Monarch butterflies use the very same trees each and every year when they migrate, which seems odd because they aren’t the same butterflies that were there last year. These are the fourth generation of monarch butterflies, so how do they know which trees are the right ones to hibernate in? Monarch butterflies are the only insect that migrates to a warmer climate that is 2,500 miles away each year.

The Monarch butterfly migrates for two reasons. They can not withstand freezing weather in the northern and central continental climates in the winter. Also, the larval food plants do not grow in their winter overwintering sites, so the spring generation must fly back north to places where the plants are plentiful. The monarch overwintering sites are under threat because of people cutting down their favorite trees to build roads, houses and farms. What will happen to the monarchs if they do not have their special trees to spend the winter?

Monarchs lay their eggs on milkweed leaves and the eggs hatch into caterpillars, eventually into chrysalises and then into butterflies. Since 1996 when scientists recorded the largest population of monarchs covering over 44 acres in the forests near Mexico City, the annual migration numbers have dropped considerably. This decline is the result of the planting of genetically engineered, herbicide-resistant crops that tend to decrease the amount of milkweed available. Last year, migrating monarchs covered less than 2 acres.
To combat this, Mexico, the USA and Canada are cooperating to create milkweed rest stops from above the Canadian border to south of the Mexican. Gardeners and homeowners along the migratory routes are encouraged to plant milkweed . And this year, a change has occurred in the migration of monarch butterflies. It began with their move north in the early spring. Beneficial weather led to larger than normal reproduction rates in Texas where they amass before heading throughout the US and Canada. The weather and the food sources continued through the spring as did their reproduction rates as the migration headed north. Recently, the first monarch butterflies have been seen entering Mexico several weeks earlier than usual which has fueled the hopes of scientists that this year's migration will show a population increase. Not huge...but considering the depleting numbers over the past years...very encouraging.
Note: As of the 2015 census in Mexico this seems to have happened.

WHAT CAN YOU DO TO KEEP THE TREND POSITIVE?

The best thing we can do to stave off the potential extinction of the Monarchs in our lifetime is to plant Butterfly Weed (milkweed) and turn our gardens into a long chain of rest stops that the migrating Monarchs can rely on as they head north and south each year.

This Spring Aberdeen Florist and Garden Center will have Asclepias curassavica 'Red Milkweed' which is, without doubt, the favorite egg laying and food plant of Monarchs. 

Clusters of attractive buds open to bright scarlet-red and yellow flowers. Tolerant of a variety of less than ideal soils. It is considered an easy-care plant that needs little attention. The blooms have bright, wonderful color and attract hummingbirds, as well as, Monarchs and is a perennial in The Sandhills.

 

 

 

We wish to thank www.learnaboutnature.com for allowing us to
quote from their article on the migration of the Monarchs.