The western population of monarch butterflies is in steep decline, according to a recent study released by the Xerces Society, having fallen 74 percent in the past two decades, from roughly 1.2 million in 1997 to fewer than 300,000 butterflies in 2015.
Studies have documented the drop in eastern populations over the past several years, but this is the first time we’ve been able to understand the risks to the western population, which resides west of the Rocky Mountains.
The population is struggling because of development around the forested groves where they spend winters along the California coast and in Mexico, and because of pesticide applications that kill vital milkweed habitat. These threats and the population decline are significant, having the potential to influence a U.S. Fish and Wildlife Service decision in coming years if the situation fails to turn around soon.
I’ve feared for many years that the monarch might reach the point that it will require protections under the Endangered Species Act – a last resort that signals a dire state for the iconic and beloved species. But a recent trip to California gave me great hope that it’s not too late to change the monarch’s trajectory.
Farmers are the lifeline
Davis Ranch is a sustainable farming operation spanning thousands of acres in Colusa, just an hour’s drive north of Sacramento. The ranch produces a variety of crops including rice, tomatoes, sunflowers and wheat to name a few. But it’s also producing a variety of conservation benefits for local wildlife and the local community.
“By implementing practices that save water, reduce waste, utilize natural fertilizers and cover crops as well as provide and protect natural habitats for our abundant wildlife, we can insure that farming will remain a way of life on our ranch for many years to come.” – The Davis Ranch Approach to Farming
John Brennan is the farm manager at Davis Ranch, where he helps the farm owners make decisions about how to manage the business to earn a profit and benefit the environment. John welcomed us to the property last week, allowing us to test a habitat quantification tool that we have been developing to better assess monarch habitat quality.
I didn’t know what we’d find at the property, since I knew there was only one small patch of milkweed. I was pleasantly surprised to not only find some fairly high quality milkweed habitat, but also to see some monarch caterpillars, butterflies and even a monarch chrysalis. Carl Stenoien, a Ph.D. candidate at the University of Minnesota who works with Dr. Karen Oberhauser at the Monarch Lab, joined us for the field test and told me that he has only seen three chrysalids in his lifetime, so it was quite a treat to see one in person.
Since we saw various stages of the monarch life cycle – eggs, caterpillars at various growth stages, chrysalids and adult monarchs – all in one milkweed patch, we know that multiple monarchs visited this site at different times. Given the size of the ranch, it’s pretty impressive that so many monarchs were attracted to this tiny roadside patch. It’s a promising sign that the habitat on Davis Ranch is serving the species well, and that with a few additional conservation practices, such as avoiding mowing during times of high monarch activity or planting native flowering plants for nectar sources, this habitat could be enhanced to support even more monarch butterflies in the future.
Where conservation and crop production meet
The end goal for the monarch habitat quantification tool is to be able to measure conservation outcomes so that incentive payments (from public or private investments) can be directed to landowners willing to protect, enhance or restore milkweed habitat on their property. We like to say that this will allow landowners to get paid for planting milkweed, just like they would with any other crop.
In the case of Hedgerow Farms, they are already doing just that.
John Anderson is the owner and founder of Hedgerow Farms, where he has been committed to growing milkweed and other native grasses, forbs, sedges and rushes to sell the seed and plants for various uses, particularly for restoration projects in the area.
Not only are the cultivated seeds helping other landowners plant milkweed for monarchs, but his production fields are a monarch haven. We saw dozens of adult butterflies flying above the rows of milkweed, stopping to feed on the flowers’ nectar. It was quite a sight.
We visited a few other parts of the property to test the habitat quantification tool, including a roadside and a small garden where milkweed had expanded outward from a few initial plantings, as opposed to the row crop formation. These sites proved to be just as robust as the production fields, with dozens, if not hundreds of monarch caterpillars feeding on the leaves.
With all of the high quality habitat available to monarchs at Hedgerow Farms, there is a huge opportunity to protect, enhance and even expand the habitat at this property to provide valuable breeding and nectaring habitat for butterflies for years to come.
Seeds of hope for the monarch’s future
More than the sheer volume of milkweed or monarchs that I saw last week, I was most inspired by the landowners’ sincere stewardship values: they wanted to grow food and plants in a way that would be sustainable for generations to come.
Besides the milkweed production fields at Hedgerow Farms, all of the other milkweed we saw – in roadsides, field edges and gardens – was planted without any financial reward, for the sole benefit of providing habitat for monarchs and other pollinators. Of course there is also some intrinsic value to the landowners in that they can feel good about helping a species at risk, and enjoy the beauty and wonder of monarch butterflies.
The trip left me feeling very hopeful about the future for monarchs, knowing that farmers and ranchers are ready and willing to help. We just need to give them the tools and support.