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The Declining Monarch Population and Three Likely Causes

The Declining Monarch Population and Three Likely Causes

For as long as I can remember, Butterflies have been my “thing.” Some people like cats, some people like roses. I love Butterflies. They represent diversity, resilience in adversity, and evolution in life. Think about it. A Butterfly begins its very short life as a caterpillar crawling on the ground, up plants, and within vines. Then, through metamorphosis, the insect cocoons for a time before emerging as a beautiful, graceful creature of flight weighing less than a gram. They’re delicate, yet the process of leaving a cocoon is a fight for life that requires real grit.

When I’m asked by people who don’t know me well which Butterfly is my favorite, I give this answer. “How does one have a favorite flavor of life?”  All Butterflies are beautiful, and I have no favorite, although I will admit the most iconic and representative of all species is the Monarch Butterfly. It captures the imaginations of children, and nature lovers across the nation, but the most amazing thing about this Butterfly is its collective migration.  These Butterflies begin an eight-month migration in the spring that takes them from Central Mexico, through the U.S., and up to Eastern Canada. During this migration four successive generations are born and die which means they’re traveling on intuition.

Since 1992 conservation organizations and citizen scientists have been documenting the migratory phenomenon. In the past 25 years a troubling trend has come to light- a steep decline in the population of the Monarch Butterfly. When I read articles about the decline of the Monarch Butterfly, or talk about it, two sets of numbers play in my mind like a broken record: 2015- 42 Million, and 2002- 500 Million. In 2015 the census of the Monarch Butterfly population was 42 Million. In 2002, during a massive storm that threatened the Monarch’s overwintering habitat in Central Mexico, 500 Million Monarchs were wiped out. What does this mean? It’s a perspective trap that illustrates how, due to complications from climate change, if the wrong storm hits Mexico during its winter season the entire population of Monarch Butterfly could be gone.

Environmental issues are not the only problems the Monarch population faces. The human factor is also an issue.  The Monarch Butterfly has a specific and complex migratory process, and part of this process includes its overwintering locations. Though small populations of Monarch will overwinter in Florida and California, the majority of Monarchs overwinter in Mexico’s Oyamel Fir Forest. This habitat is being lost to legal and illegal logging. The Monarch Butterfly Biosphere Research and National Commission of Natural Protected Areas are working to preserve this habitat. However, the logging is still happening.  According to this study, another habitat loss to the human variable lies along the Monarch’s migration path. Monarchs breed during the summer, and Milkweed plays host to this process. However, a dramatic increase in the agricultural use of herbicide resistant crops called “Roundup Ready Crops” that are genetically modified to be resistant to glyphosate- a broad spectrum herbicide that kills everything other than the resistant crop including Milkweed- has contributed to the loss of Milkweed in prime migration routes. This factor is two-pronged.  Because of the use of these crops and herbicides, Monarchs come under threat during their migration because they have nowhere safe to rest, eat, or breed on their journey so they’re dying in route. The herbicide is killing everything they need during their migration.

With this information the desire to do something can cause a stir. Climate Change is such a massive issue, and the individual person has no way of taking large enough measures to ensure the massive Pacific weather systems of 2002, 2004, and 2010 don’t repeat. This requires collective work and attention over a long period of time. Doing our part as individuals is one way to contribute to the collective effort.  The human factor is also something that the individual can address. A loss of food sources and safe havens for rest in the Monarch’s migratory path is a contributing factor to the decline of population because our agricultural practices are starving these majestic creatures during their migration. Planting flowers like Zinnias, Coneflowers, Miss Molly’s, or Butterfly Bushes will offer much-needed nectar to the Monarch during its migration. Keep in mind that Monarchs only consume Milkweed as caterpillars, but it’s still a necessary plant because Milkweed is the only host plant to Monarch breeding.

Another action that has great potential to help the Monarch is to have the species protected under legislative action. A decision is in the works and due to be made by 2019.

You Can Help The Monarchs

The Monarch Butterfly is a majestic creature, and an image of natural beauty and grace. Its existence is threatened by climate factors, and human interference. There is much that can be done to help which includes small steps like planting food source, and breeding ground flowers along the migratory path of this Butterfly, protecting its overwintering habitat, and giving attention to the use of an invasive herbicide which ultimately kills everything except for specific crops. One person’s voice is always a tool to be used for the larger picture, and small individual actions in your own garden have an immediate impact.

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