Grasslands, birds, monarchs, pollinators and more

The world has been changing rapidly, but the changes are such that most of us aren’t aware of what has changed or what is missing.

As an ecologist, I’m alert to change but, like most people, I often miss the indicators. Crows are down. The numbers aren’t what they used to be. Did you notice? I did but well after I should have. Crows and other corvids declined due to their susceptibility to West Nile Virus. I anticipated that the numbers would recover once the virus had run its course. They did, somewhat, but the numbers are not what they were before West Nile, and now they may be declining for other reasons.

What about other birds? Did you catch the headlines in September announcing the results of a study of bird population numbers in the United States over the last 50 years? The numbers have declined by 29% or 2.9 BILLION birds! The biggest losses, a negative 53% (>700 million) occurred, in 31 grassland species. Wow! That’s staggering, and these results give rise to many questions. Why were the losses highest across the vast grasslands that dominate areas east of the Rockies in the United States and Canada to eastern Illinois? What factors contribute to these losses? Probable causes include loss of habitat, fragmentation, neonic insecticides, herbicides and mowing. Of these, there are data on habitat loss due to the intensification of land use in agriculture and the continuous march of development. While it is likely that the other factors contribute significantly to habitat loss and losses of specific species, attaching specific numbers or even assessing which is the most important isn’t possible at this time.

Land use changes have been hard to track often resulting in long lags in reporting. Recently, the urgency of knowing what is happening in real time has resulted in more rapid updating providing us with a better measure of conversion rates each year. The impact of the Renewable Fuel Standard (RFS) on land use was a shocker. The publication of a report entitled “Plowed Under” by Faber et al. in 2012 indicated that nearly 24 million acres, an area nearly the size of Indiana, had been converted from one land use classification to another from 2008 through 2011. Subsequently, Lark et al (2015) showed that 77.7% of that acreage involved the conversion of grassland to cropland. Another report from the Lark team in 2018 indicated that over 10 million acres of grassland had been converted to crops from 2008-2016. The Plowprint Report by the World Wildlife Fund in 2018 indicated that another 1.7 million acres were converted to cropland in 2017. The bottom line is that grasslands are being lost at an average rate of more than a million acres per year.

What is less clear is how much habitat is being lost to development in grasslands. It’s probable that these losses are also in the range of a million acres a year. Further, some losses may not be accounted for. In many areas in the Midwest, growers have reduced the distance from the edge of the field to the edge of the road, leaving only low diversity grass filled margins.

There is no doubt that the grasslands are in decline and we are losing birds, but does it matter? It does. The loss of grasslands signals that we are not only losing birds, but also pollinators, monarch butterflies, small mammals and the raptors and other predators that feed on them. Further, without the pollinators, we will lose both plant and insect diversity further eroding the connections that sustain these ecosystems.

Do we want to live in a world without birds and pollinators? The larger question may be, can we? These ecosystems support us. We are dependent on the richness of these environments. The soil is alive. It’s a matrix that supports a complex web of life, and the organisms within it are often connected intimately with the health and well-being of the plant and animal life above. These connections are destroyed or modified through changes in land use and the addition of chemicals in the form of fertilizers and short and long-lived insecticides and herbicides. It’s fair to ask if, collectively, we know what we are doing. What will be the costs of our quest to extract everything we can from grasslands? Is there another dust bowl in our future?

To counter our destructive tendencies, there is a strong movement to restore habitats both broadly and for specific species. The bird study shows that, in contrast to the general decline, waterfowl numbers have increased over the last 50 years. So have eagles, peregrine falcons and a few other species. These successes are due to habitat restoration and protection. There are also attempts to restore grasslands. The challenge is massive. To keep pace with the annual rate of loss, we need to restore more than a million grassland acres a year. That requires dollars, seeds, locations, boots on the ground and more.

Can we maintain or even increase that rate of restoration? Surely, we can. Will we, is the question. I deal with this issue on a regular basis. Monarch numbers have declined by about 80% over the last two decades, and the crash in the population during the winter of 2013–2014 led to a petition to the Department of the Interior to declare the monarch a threatened species.

At Monarch Watch, we have made it our mission to do what we can to sustain the monarch migration. This mission involves getting people, businesses, states and federal agencies to plant milkweeds, the host plants of monarch caterpillars. The task is immense. A major study indicated that 1.4 BILLION milkweed stems need to be planted, mostly in the Upper Midwest, to restore monarch numbers to a level sufficient to buffer the population in the event of extreme losses due to winter storms and other weather events.

We have made a small dent in this number. To date, over 27,000 Monarch Waystations, generally small gardens or restoration sites containing milkweeds and nectar sources, have been created and registered. In addition, working with nurseries, we have facilitated 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. They have charisma and are known to the public, and the public is strongly interested in monarch conservation. By saving the monarch migration through the restoration of grasslands we will save many other species. It’s our mission, but all can contribute. Plant milkweed!

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This article was also published in the recent Winter 2019 Wild Ones Journal (Vol. 32, No. 4, pp 26–28).