Dr. Chip Taylor of Monarch Watch provides a much expandied piece on this topic in his 2020 blog post.
Why Monarchs? While monarchs are intrinsically important, conserving monarchs matters for more than just their own protection. We’re exploring the ways that monarch habitat and conservation helps people, other wildlife and the environment in this ‘More than Monarchs’ series! Join us to learn more.
I’m alert to change but, like most people, I often miss the clues. For example, the American crow, a very common bird throughout the United States, decreased in numbers as West Nile Virus swept through the country. Did you notice? It took me awhile to do so. Crows have recovered a bit, but the numbers are still low.
What about other birds? According to a 2019 study published in the journal Science, bird population numbers in the United States and Canada have declined by 29% or 2.9 billion birds. The biggest losses, 53% or more than 700 million birds, occurred in 31 grassland species. That’s staggering! While many factors appear to have contributed to these declines, habitat loss is a major driver.
The pace of the loss of grasslands has been rapid and dramatic. The “Plowed Under” report by Faber et al. in 2012 indicated that nearly 24 million acres, an area nearly the size of the state of Indiana, had been converted from one land use classification to another in four years due to the impact of the Renewable Fuel Standard (RFS). In 2018, Lark et al. indicated that more than 10 million acres of grassland had been converted to cropland in eight years. Grasslands are still being lost at an average rate of more than a million acres per year and these losses appear likely to continue.
The loss of grasslands signals that we are not only losing birds, but also small mammals and the raptors and other predators that feed on them. In addition, we are losing pollinators, monarch butterflies and a diverse array of insects and plants that are unique to these habitats. The life cycles of plants, birds, insects, and other wildlife are intimately connected in complex food webs. These webs are largely based on the interactions between pollinators and the plants they pollinate. These interactions provide the seeds and vegetation that are fed on by insects and they in turn are fed on by songbirds and small mammals to feed themselves and their babies and these birds along with small mammals, whose lives are also dependent on vegetation and insects as food, serve as food for larger predators. Without pollinators we lose both plant and insect diversity further eroding the connections that sustain all the species that share these ecosystems
We are dependent on the richness of these ecosystems. The diversity of life above and below ground in these areas provide an ecological matrix that supports a complex web of life. There is a strong movement to restore habitats both broadly and for specific species, like monarchs. This movement involves getting people, businesses, states and federal agencies to plant native milkweeds, the only host plants of monarch caterpillars, as well as other critical nectar sources to help fuel their migration. The task is immense. A 2017 study by Thogmartin et al. indicates that 1.4 billion additional milkweed stems need planting to restore the monarch population.
Multiple organizations, agencies, municipalities and universities are planting native milkweed and other native wildflowers, creating pockets of grassland habitat throughout North America. One example is Monarch Watch. This organization has spurred the creation of over 27,000 Monarch Waystations, small gardens or restoration sites containing native milkweeds and nectar sources. In addition, they work with nurseries to facilitate the production and distribution of a million milkweed plugs (small plants) for restoration projects throughout much of the United States.
Monarchs are a gateway species for grassland conservation. They have charisma and are widely known in the public. By working together to save the monarch through the protection and restoration of grasslands we will save many other species, like songbirds, deer, and foxes. Everyone can help by planting native milkweed and nectar sources and supporting the organizations, agencies, and efforts working to protect and restore these critical areas of the landscape.
Grasslands conservation is just one example of how the work we do for monarchs can make a difference in many ways. What are the co-benefits of monarch conservation that matter most to you? Keep following our “More than Monarchs” series to hear more stories of what monarchs can do for us, our communities and our world.
(Article adapted from Dr. Taylor's original text by the Monarch Joint Venture Communications Working Group and NAPPC Monarch Taskforce’s More than Monarchs Series. The Monarch Joint Venture is a 501c3 nonprofit organization and a national partnership of federal and state agencies, non-governmental organizations, businesses and academic programs working together to conserve the monarch butterfly migration. The content in this article does not necessarily reflect the positions of all Monarch Joint Venture partners. Header photo by Angie Babbit.)
References
Faber, S., Rundquist, S. & Male, T. (2012). Plowed under: How crop subsidies contribute to massive habitat losses. Environmental Working Group Report.
Lark, T. J., Salmon, J. M. & Gibbs, H. K. (2015). Cropland expansion outpaces agricultural and biofuel policies in the United States. Environ.Res.Lett.,10 044003 doi:10.1088/1748-9326/10/4/044003
Lark, T.J., Spawn, S.A., Bougie, M. et al. (2020). Cropland expansion in the United States produces marginal yields at high costs to wildlife. Nat Commun, 11, 4295. https://doi.org/10.1038/s41467-020-18045-z
Rosenberg, K. V., Dokter, A. M., Blancher, P. J., Sauer, J.R., Smith, A. C., Smith, P.A., Stanton, J. C., Panjabi, A., Helft, L., Parr, M., and P. P. Marra. (2019). Decline of the North American avifauna. Science, 366, 6461, 120-124.
Thogmartin WE, Diffendorfer JE, López-Hoffman L, Oberhauser K, Pleasants J, Semmens BX, Semmens D, Taylor OR, Wiederholt R. 2017. Density estimates of monarch butterflies overwintering in central Mexico. PeerJ 5:e3221 https://doi.org/10.7717/peerj.3221
World Wildlife Foundation. (2018). 2018 plowprint report. https://www.worldwildlife.org/publications/2018-plowprint-report