14
Mar
Monarch Butterfly Numbers Keep Declining
(Beyond Pesticides, March 14, 2018) The annual count of Monarch butterflies overwintering in Mexico shows declines from last year’s numbers—a 15 percent decrease –according to figures from an official Mexican government count in the winter of 2017. These numbers underscore how at risk the iconic animal is, with a possible collapse of migration if populations are critically low.
Monarch butterflies (also known as Eastern Monarchs) embark on an impressive migration every year. Roughly 99 percent of all North American monarchs migrate each winter to oyamel fir forests on 12 mountaintops in central Mexico. Scientists estimate the population size by measuring the area of trees turned orange by the clustering butterflies. But for the second year in a row, its numbers are declining — 2.48 hectares of occupied winter habitat is down from 2.91 hectares last winter. Apart from partial rebounds in the winters of 2001 and 2003, numbers have gone down steadily since 1996. Overall monarchs have declined by more than 80 percent over the past two decades.
Earlier this year, Western Monarchs – those found west of the Rocky Mountains – overwinter in coastal California forests, were also found to be declining 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. 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 year’s drop in Monarch populations is attributed in part to unseasonal weather last year including late spring freezes that killed milkweed and caterpillars, and an unseasonably warm fall that kept late-season monarchs from migrating. 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. An estimated 165 million acres of breeding habitat in the United States has been lost to herbicide spraying (particularly on GE cropland) and development.
In 2014, conservationists led by the Center for Biological Diversity and the Center for Food Safety petitioned the U.S. Fish and Wildlife Service to protect the butterfly under the Endangered Species Act. Monarchs are threatened by a host of sources destroying their habitat and food, but studies have shown that a main source of their catastrophic demise decline has been genetically engineered crops, engineered with resistance to Monsanto’s Roundup pesticide, which has dramatically increased the pesticide use on their habitat. The Fish and Wildlife Service’s initial decision was that endangered species protection may be warranted, and pursuant to a court victory the Service agreed to make a final decision by June 2019.
Later last year, over 100 conservation and environmental groups urged the federal government to increase funding to protect and conserve monarch butterflies. The groups sent a letter to the U.S. Department of Agriculture (USDA) to do more to help the imperiled butterfly. The letter requests the agency increase the allotment of conservation funds from $4 million- spent last year- to $100 million. The increase in funds is needed for efforts to increase milkweed habitat. Currently, USDA has taken some steps to protect monarchs. These include the implementation of the Monarch Butterfly Habitat Development Project and support of the Monarch Butterfly Conservation Fund. But, according to the letter, “Restoring the monarch butterfly and its habitat will require a substantial contribution from the agricultural sector and strong leadership…”
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.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Center for Biological Diversity