The eastern monarch is in trouble, and now is the time to help (no science degree required).
NASHVILLE - The chrysalis of a monarch butterfly is one of the most beautiful things in nature. Brilliant emerald green and flecked with gold, it is an exquisite gem that holds even more exquisite promise.
The day before a monarch emerges, its chrysalis turns dark, almost black, but if you keep a light on, you can see the shape of the living orange wings inside. The wings are lined with black veins like stained glass in a cathedral. They are still strongly bent, but bear, in miniature, the shape of the wings of an adult butterfly. At this stage, it is possible to determine the sex of the butterfly even before it leaves the chrysalis, simply by observing the thickness of those black veins that frame the bent wings.
I have been trying to grow monarchs in my family room for two summers, with mixed results. Last year some of my mail order caterpillars pupated and none survived to become a butterfly. This year I've had better luck: After watching a monarch lay eggs on milkweed in my own garden, not once but twice this season, I brought some eggs indoors to protect them from predators. I released seven healthy butterflies in June and four more last week, a perfect egg-to-butterfly survival record. But I don't know how many eggs hatched in the garden, or how many of those that hatched survived. Even with their bright yellow stripes, monarch caterpillars are adept at camouflage.
As a species, the Eastern Monarch, an iconic butterfly that migrates 3,000 miles each year, is in serious trouble. A changing climate is part of the problem, which endangers the monarch's Mexican wintering grounds and spawns extreme weather events that can destroy millions of migratory butterflies. And pesticide drift can poison caterpillars even when they are not the target pest.
Monarch caterpillars are never targeted, in fact, because monarchs are important pollinators that don't eat crops or damage gardens. Their caterpillars eat only milkweed, which was once ubiquitous along American highways and in the margins between fields on small farms. The greatest danger to the monarch butterfly is the disappearance of milkweed due to habitat destruction and the widespread use of herbicides, such as Roundup, both on commercial farms and in state highway departments.
According to the Center for Biological Diversity, which advocates adding the monarch to the federal list of endangered species, the North American monarch's population has fallen more than 80 percent in the past two decades. This year, the migratory population of the butterfly, some 93 million, was significantly lower than a year ago. And scientists believe that the population needs to reach at least 225 million to avoid extinction.
Raising monarchs within a climate-controlled family room is a fascinating hobby, but it is not the way to save the species. The butterflies I released this year, even combined with the thousands upon thousands of butterflies released by dedicated monarchical administrators across the country, will make little difference to a population that is still well below sustainable numbers. What the monarch needs to survive is more milkweed.
As Laurel Wamsley of NPR, the public radio network, recently reported, a new project at the Field Museum in Chicago aims to help by planting milkweed in urban areas along one of the main migration corridors of the monarch. A team led by Abigail Derby Lewis, a senior conservation ecologist at the museum, investigated potential planting sites in Austin, Texas, Kansas City, Chicago, and Minneapolis-St. Paul. They discovered something surprising: there is already a large number of milkweed growing in cities - 41 million plants.
And there was plenty of room to double that number, particularly if more people were planting milkweed in their own patios and flower beds. “In many ways, if you plant it, they will come,” Dr. Lewis told NPR. "It is a wonderful, almost instant gratification that people feel and are empowered to make a difference."
There are many varieties of milkweed, so it is best to choose the ones that suit your region and growing conditions - some varieties do well in full sun and can tolerate drought, while others prefer boggy conditions. Perhaps counterintuitive, the fall is the best time to plant milkweed because the roots have time to grow deep and establish themselves before the plants are stressed from the summer heat. (For information on which varieties to plant in your area and where to find seeds, check out Monarch Watch, here.)
I had to try several varieties before deciding on two that do not require pampering or care. Ultimately, the monarchs came and laid eggs in my garden. Each female monarch lays up to 500 eggs in her short life because, as with most insects, survival depends on waste. Monarch caterpillars can be the prey of predators, parasites, and disease, but if there is enough milkweed to support them, at least some of the caterpillars will eventually survive to form a chrysalis.
Last week, he had released 10 healthy monarchs, but he had yet to see a butterfly emerge from its chrysalis. It is amazing to see a caterpillar egg hatch (the baby is so small that a magnifying glass is needed to make sure a hatching is actually occurring), and it is equally amazing to see a mature caterpillar contort when shrugging. of its skin and forms a chrysalis. But the miracle of all miracles has to be the emergency itself, and it happens so quickly that it's easy to miss.
Finally, last Monday, with the last chrysalis of the year, I saw it.
What a gift it was to see a monarch butterfly pierce through its shell, crawl and spread its wings. What an unspeakable gift to watch as its proboscis unfolds, to watch its delicate legs cling to the consumed chrysalis, as the fluid fills its wings and begins to take the shape of the most recognizable butterfly in the world.
Margaret Renkl is a contributing opinion writer covering flora, fauna, politics, and culture in the American South.
Original article (in English)