The Western Monarch Thanksgiving Count began in 1997, when scientists first noticed declines and started to track the population.

In the years since, the western monarch butterfly population (the smaller of the two North American populations, which overwinters on the California coast) has dropped dramatically, and this year’s preliminary data is especially alarming.

Early reports on this year’s count suggest that populations have dropped 86 percent since last year, with the population at less than 0.5 percent of historic levels. Approximately 20,000 monarchs were counted at the monarch’s overwintering sites this Thanksgiving, compared to 148,000 counted last year. The Xerces Society estimates that the overall population will be around 30,000.

This is a grim number, especially when you consider studies showing that 30,000 butterflies is the average population needed to avoid a complete collapse of the western migration , and extinction of the entire western population.

It’s clear that western monarchs cannot survive even one more year of decline like this one.

How did we get here?

The low numbers were not a surprise for those of us tracking the butterfly’s migration.

Overall, monarchs were seen in lower abundance across the western range, with lower utilization of available habitat, though scientists are unsure what exactly caused such a dramatic decline this year. Theories include the fierce fire season, spring storms and the lingering effects of a historic drought. But these are just a few climate-related factors contributing to the long-term decline of the species.

Even without this year’s harsh climate impacts, the western monarch population is down 97 percent since the 1980s. Other major drivers of this decline include habitat loss throughout the range, driven by large-scale land conversation across the western agricultural landscape.The western monarch butterfly population saw a sharp 86% decline since last year, confirming the species is still facing numerous obstacles in its fight for survival Click To Tweet

The monarch butterfly relies on flowering plants for nectar and on milkweed plants to lay their eggs and for caterpillars to eat. In California and across the West, much of the native milkweed and flowering plants have been eradicated on agricultural lands as a result of broad herbicide applications.

If we’re going to change the trajectory for the monarch, we need to not only address climate change, but also protect, restore and enhance milkweed and wildflower habitat on working lands.

A strategy to save the butterfly

Recent declines have energized those fighting for the monarch. Across California, EDF is partnering with farmers who want to conserve this iconic species – farmers whose families have worked the land for generations and have seen the decline of the monarch firsthand.

We’re working with these farmers to restore key patches of monarch habitat in places like the Central Valley, where monarchs travel in the spring and fall on their journey to and from the California coast. We’re also supporting more public funding for monarch and pollinator conservation, with a major recent success in the passage of AB 2421, a bill that provides $3 million for monarch conservation in California.

This February, we’re hosting a meeting to assess the state of the science on the western monarch population and determine an immediate no-regrets strategy to save the species.

Through these initiatives, we hope to restore 30,000 acres high-quality monarch habitat in California over the next 10 years to bring stability and resiliency back to the western population.

We still have a chance to turn things around for the western monarch and avoid the extinction of a beloved and iconic species. But it is imperative to act now.