07
Feb
Western Monarch Butterfly Count Lowest this Decade, Raising Fears of Extinction
(Beyond Pesticides, February 7, 2018) New data from the California monarch butterfly count indicate that the western 
population of the species is continuing to decline at an alarming rate, with scientists and conservation groups pointing to man-made factors like logging, climate change, and herbicide use on genetically engineered (GE) crop fields as primary drivers. The annual California count of western monarch butterflies stationed volunteers at 262 sites, more than ever before, yet at 200,000 butterflies counted, the numbers nearly matched the lowest level recorded this decade, when only 145,000 butterflies were seen in 2012. The decline of these iconic butterflies demands swift action from lawmakers and regulators to protect their dwindling numbers.
Dramatic declines in monarch populations mirror continuing declines in honey bees and other wild pollinator species. Species declines may be even broader than pollinators, affecting all insects in general. Research from Germany recently found that insect abundance declined 75% over the last 30 years, owing the results primarily to agricultural intensification.
The western population of monarch butterflies – those found west of the Rocky Mountains – overwinter in coastal California forests. Throughout the warmer months, female butterflies will lay eggs only on milkweed, making these plants critical to the survival of the species. Adults forage on nectar from a range of flowers in Arizona, California, Idaho, Nevada, Oregon, Washington, and Utah, before returning back to their forest groves for the winter.
According to past data from the Xerces Society, which began its annual monarch count in 1997, at that time over 1.2 million monarch butterflies were found to overwinter in California’s central coast. When compared to the count that took place just one year before in 2016, western monarch numbers are down by 100,000 butterflies. In the 1980s, over 10 million monarchs spent the winter in California forestland.
A study conducted by the U.S. Fish and Wildlife Service last year on the butterfly’s dwindling population indicates that western monarchs have an extinction risk of 86% within the next 50 years. Within only 20 years, the risk is still 72%. “This study doesn’t just show that there are fewer monarchs now than 35 years ago,” said study author Cheryl Schultz, PhD, an associate professor at Washington State University Vancouver. “It also tells us that, if things stay the same, western monarchs probably won’t be around as we know them in another 35 years.”
Eastern monarch populations have also been declining over the past several decades. A 2017 study by the World Wildlife Fund and other conservation groups determined that the population has decreased by 80% since the 1990s, further warning that within 20 years eastern monarch’s iconic migration route from Canada to Mexico could completely, and likely irreversibly, collapse.
A range of factors have been linked to monarch declines. Natural events such as extreme weather, wildfires and smoke have been discussed, but a greater emphasis has been placed on manmade impacts. Climate change can alter the migration patterns. Legal and illegal logging and development in Mexico and coastal California has eliminated significant habitat for monarch overwintering. And milkweed, the sole source for female monarchs to lay eggs and perpetuate the species, once abundant throughout the entirety of the United States, is now nearly eradicated around farmland through which the species makes its annual migration.
Those wishing to support their local monarch populations can find sources of milkweed for their particular climate by visiting the Xerces Society milkweed seed finder. Individual residents taking action is a critical part of the long-term solution for monarchs, but broader changes in land-use and agriculture are needed to ensure that these species will still be around for another 50 years.
GE crops, able to tolerate repeated sprayings of a particular herbicide, whether glyphosate, dicamba, or 2,4-D, are making the edges and roadsides around farm fields where milkweed often grows desolate, lifeless areas. Further compounding a lack of milkweed is the additional use of insecticides on these fields. Chemical company encourage farmers to use systemic neonicotinoids to coat the outer layer of their GE seeds in an unnecessary attempt to protect it from pests. Unfortunately, both herbicides and insecticides don’t stay where they’re originally applied. Herbicide use on GE-tolerant crops drift and kill milkweed and other plants pollinators rely on. Coated seeds will often drift during planting, or run-off into soil and groundwater afterwards, contaminating these same pollinator-friendly plants. Research published in 2015 found that milkweed contamination from drifting neonicotinoids made the plants toxic to larvae which rely on it as its sole source of food once hatched.
Changing the way we farm can make an immense difference for the protection of monarchs and other pollinators. Help pollinators by only purchasing products that don’t allow GE crops or toxic systemic insecticides. Certified organic agricultural practices successfully produce profitable yields while managing to not poison the air, water, soil, vegetation, and other wildlife around their farm.
But changing agriculture also requires additional authority to institute protections for these important pollinators. Take action today! Tell the National Resource Conservation Service to significantly increase the amount of funding spent on monarch conservation and the habitat restoration, and ensure that restored habitat is not poisoned with hazardous pesticides.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Xerces Society, Reuters
