The Eagles Knew Better (but perhaps not the horses)

 “Many so-called specialists thought this would be impossible,” he said. 

“The eagles had a different opinion.”

Red deer (elk) and tarpan (horses) in a new wilderness, sort of.

Franz Vera was speaking of the Oostvaarderplassen – an ecosystem reconstruction on 15,000 acres in the Netherlands, 30 minutes from Amsterdam. Vera and colleagues are building a Paleolithic landscape that includes great herds of mega-fauna including extinct aurochs (giant cattle) and tarpan (original horses), or at least their ghosts, bred back to something like wildness from the most ancient strains that survive. 

The white-tailed eagle narrowly escaped extinction. They were said to need mature, tall trees to nest and hadn’t bred in the Netherlands since the Middle Ages. A pair showed up at Oostvaarderplassen and built a nest “nearly the size of an armchair. It seemed ready to topple the scrawny tree it was perched in,” according to an engaging December 24, 2012, New Yorker article by Elizabeth Kolbert. 

Experts said they wouldn't show.

It feels peculiar for a North American restoration ecologist to read about the Oostvaarderplassen – even though the whole project has its roots here. The “re-wilding” concept was developed by American conservation biologists Michael Soule and Reed Noss, who in turn drew some inspiration from the prairie restoration movement of the Midwest. But what’s so peculiar is the lack of any discussion about plants, in either Kolbert’s article or any of the top Oostvaarderplassen choices on Google. 

Many North American ecosystem restorations have been rightly criticized for not paying enough attention to animals. The Oostvaarderplassen work seems all animal. Of course, the Europeans have no counterpart to “natural area” in the American sense. Their original, high-quality plant communities were grazed, plowed, and cut out of existence millennia ago. In some ways the Oostvaarderplassen is a big farm. By winter there’s no grass left, and the charismatic grazers are fed hay. 

Restoring the aurochs to wild Europe is much like restoring the mammoth to the ancient wilds of North America. 

Oostvaarderplassen has about 1,000 tarpan (horses), 300 aurochs-like cattle, and about 3,000 red deer (elk). They've been joined by huge numbers of geese, egrets, and other birds. Notice the possibly nervous heron, below left. 

No one speaks of restoring the wolf, lion or bear – all wiped out in most of Europe long ago. Of course Oostvaarderplassen, about the size of the Palos forest preserves, is too small for big carnivores.

Enter "Rewinding Europe" – launched by “two Dutchmen, a Swede, and a Scot.” As of 2012, they had raised six million Euros to pursue five rewilding areas - each fifteen times bigger than Oostvaarderplassen.  

2026 Update

Oostvaarderplassen failed in one big way. Without predators, the assumption was that the large animals would just die of old age or starvation, as if that were good and natural. But in the absence of predation, during the winter of 2017-2018 of the reserve's 5,200 large animals, almost 3,300 cattle, horses, and deer died or were shot in badly emaciated states to reduce their suffering. There was public outcry and a consensus that something was wrong. 

The Dutch Forestry Service now manages and has expanded the reserve. Following studies, they removed all the horses and regularly relocate or shoot other large animals to reduce the populations. The reserve remains a hugely successful habitat for birds and other animals. It's popular with visitors. Efforts to connect it with a park in Germany have terminated. 

Inspired by early successes at Oostvaarderplassen, related Rewilding Europe initiatives now cover large areas around Europe, from Sweden and Scotland to Romania and Ukraine, reporting many successes, especially for birds.      

Two Notes

This post (thought-provoking?) is an update on a 2012 post in our predecessor/partner blog, Vestal Grove. 

The better-managed bison reintroduction to Nachusa Grasslands is an interesting comparison for people who want to wrestle with what these issues mean about nature and its conservation. 

Quality Assessment - Tomlinson case study - apparent loss from 1996 through 2015

THIS POST IS A DISCUSSION DRAFT as of Oct 1, 2026. PLEASE DON'T QUOTE UNTIL IT'S FINISHED. BUT COMMENTS AND SUGGESTED EDITS ARE VERY WELCOME.

Important note: This post is not about the current state of this Nature Preserve nor is about the management in recent years. It's about the state of the preserve as seen by studies dated 1996 and 2015. It focuses on the question of whether we have systems of monitoring and analysis of ecosystem quality (or health or integrity) that are adequate to assure the long term health of the preserves. 

In 1985 Tomlinson was permanently protected as a one-acre Illinois Nature Preserve. Originally called Tomlinson Cemetery Prairie, this remnant, according to the Nature Preserve website, “is one of only two savannas protected as nature preserves in the Grand Prairie Section of the Grand Prairie Natural Division.” High-quality savannas are even rarer than prairies. This is a very precious site. 

The Illinois Nature Preserves System was once a world model. It assembled resources to rescue and provide permanent legal protection to our most important remnants of biodiversity. But increasingly, questions have been raised about how well the quality of the preserves in that system is being maintained. 

In 2020, this blog cited concerns about declines in quality of 47 Nature Preserves in all parts of the state. One entry read:

Champaign County: Tomlinson Pioneer Cemetery Prairie Nature Preserve: Seems not to have been burned sufficiently often. Domes of dense hazel have shaded out the previously diverse vegetation over substantial areas.

But it does get burned at least occasionally as shown below in two photos referred to as "recent" on a history website named Clio.  

So how concerned should we be? 

Three studies help us evaluate. In a 2003 study, Bowles and Jones determined that high-quality prairies and savannas which get burned less often than every two years were declining in quality. Ultimately, insufficient burning means losing species and genetic alleles – defeating the very purpose of these preserves.

Friends of Illinois Nature Preserves have been working with anyone interested to assemble information on the state of the preserves. In the process, Friends field rep Stone Hansard came across a scientific paper on Tomlinson by Ellis and Wolz published by the Illinois State Academy of Science in 2015. 

They compared their data to that from nearby prairies, which are thought to be similar to savannas in many respects, and in the absence of high-quality savannas may indeed be the best models. The authors provided these assessments: 

●      Species richness and diversity at Tomlinson is comparable to prairie and savanna remnants in the Region 

●      The number of native species recorded at this small preserve (103) is similar to reports from other prairie remnants 

●      We recorded more native species than Betz and Lamp (1989) in their survey of 29 prairie remnants (range of 30-89 native species per site) and their survey of eight savanna remnants (range of 33-75 native species per site) 

●      An FQI of 32.7 (36.1 native species only) shows relatively high floristic value. Prairie sites with an I of 35 or higher are considered good quality 

●      The relatively high species richness in this small preserve is comforting from a conservation perspective 

The data in this study make an important contribution. A person could conclude from it that the condition of the site was fine. Given the lack of resources for such studies, the argument could be made that this evaluation was sufficient. 

But as it turned out, a third paper, this one by Bowles and McBride, included data on this same preserve seventeen years earlier. This paper was a report to the Illinois Department of Natural Resources. Ellis and Wolz seem not to have known about this “before” data and didn’t use it to assess trends.  

Data Sets Compared

Both Tomlinson studies based their analysis on quadrat data. In 1996, Bowles and McBride highlighted eight species as especially significant; they comprised 50% of total relative cover (basically, how much total leaf surface is attributable to the various species). These eight species “dominated” the plant community in 1996. 

One way to compare is “floristic quality assessment.” Key to this approach are the various species’ Coefficients of Conservatism (C). Higher numbers suggest a community of greater quality, integrity, or health. In the table below we compare the species that comprised 50% of cumulative relative frequency in Bowles and McBride with the comparable eight species in Ellis and Wolz. 

The mean C for the eight most common species in the two studies were as follows: 

	1996	2013	% decrease
Mean C	4.5	3.1	31%

With good management of a natural area, we would expect the Mean C of the dominant vegetation to remain stable or increase. A drop of 31% in less than two decades suggests a major loss in quality. Therefore this result is troubling. 

The meaning of the above disappointing numbers becomes clearer when we compare the two dominant plant lists. In 1996 the eight species that comprised half the relative cover (roughly equivalent to “most common”) are shown in Table 1a.

All the species in Table 1 (except the “weedy” wild lettuce) are characteristic of high-quality savannas. Under normal conditions they, or others like them, could be expected to remain the most common in this preserve. 

Table 1. Most common plants in 1996

Scientific Name	C	Common Name
Andropogon gerardii	5	big bluestem
Calystegia spithamaea	10	dwarf bindweed
Corylus americana	4	American filbert
Elymus canadensis	4	Canada wild rye
Euphorbia corollata	3	flowering spurge
Helianthus hirsutus	5	bristly sunflower
Lactuca canadensis	1	wild lettuce
Sorghastrum nutans	4	Indian grass

Table 1b shows the comparable species list in 2013.

A first warning sign in this data is that three of the most common species in 2013 suggest degradation: Kentucky blue grass, black raspberry, and Canada goldenrod. Indeed, Kentucky bluegrass, a species said to be associated with insufficient burning, was the second most frequent species recorded in 2013 (in 90% of the plots). 

It’s worth it for conservationists to learn to understand such measures and indicators. We who care need to be well-informed, to set our own priorities. Where should we volunteer to help? What should we advocate for? Where should we contribute funds? How do we compellingly make our voices heard? 

Government programs don’t work if left to the politicians and staff alone. More “citizen scientists” and  dedicated volunteer advocates are needed. As the preserve system has grown, the budget and staffing have shrunk, possibly because most people who care don’t know that there’s a problem. Are many Nature Preserves facing declines like those faced by Tomlinson? Is there a practical way to evaluate all the Nature Preserves? How confident are we that we’re not letting their quality slip away? 

In the early days of the Nature Preserve System, people thought that we could mostly just erect fences and let nature “take its course.” Sadly, in recent decades, a variety of stresses have overwhelmed the capacities of natural areas to manage themselves. The elimination of predators. reduced fire frequency, introduction of exotic species, climate change, fragmentation, and urban sprawl took their toll.

The 639 Illinois Nature Preserves total 125,284 acres. The value of this land, based on averaging various sources is $6.3 billion dollars. We, the public, paid for that land, through donations, tax breaks, and in other ways. That’s a wise investment in precious, rare, and irreplaceable biodiversity. Quality preserves also provide many other public benefits. And yet, large parts of this nature are still uncared for or under-cared-for. Many seem to be degrading as a result of a lack of needed resources.

The Nature Preserves System needs a better approach to studies and monitoring. For example, if an academic or citizen scientist is attempting to conduct a helpful study, there should be someone who could click a button and get access to a list of other studies on the site. 

Three Photos

Two photos from Matt Evans may help readers to visualize this preserve. They are from 2019.

The orange leaves are the shrub hazel.

 

Hazelnut bushes and young oak trees are a natural part of a savanna. But diverse and conservative herb vegetation is critical to a savanna preserve's biodiversity. If the woody vegetation becomes so dense that it shades out and kills off much of the herb diversity, a large part of the value of the preserve is lost. 

Backstory

What’s important about Nature Preserves is that they are the last surviving habitats for hundreds of species of now-rare and interdependent plants and animals. 

For any species of plant to be adequately conserved, it needs a full complement of its genetic diversity. That typically requires a population of 50 or 100 individuals, or more. Next, each plant species has other species associated with it (and often interdependent with it).These associated species include animals, fungi, other soil biota, and more. It has been estimated that for every plant there are an estimated 10 associated animal species. The easiest to monitor are the plants. 

If numbers of plants and animals (mostly invertebrates, including pollinators and predators that help keep the system in balance) fall below what it takes to survive disease outbreaks, droughts, fire, etc., the system may gradually lose sustainability. Then the many diverse species are replaced by a few common ones. As species and genetic richness are lost, overall survivability of the ecosystem declines. For more details on biodiversity, click here. 

Monitoring by simple species counts is insufficient. One plant of a species surviving makes the list look good, but most genetic diversity of that species has likely been lost, and any species of interdependent pollinators or other animals are likely gone as well. 

Miscellaneous Notes:

Bowles and McBride sampled only once. As Ellis and Wolz sampled throughout the growing season (six times), they were able to list an additional 54 species, indicating more complete sampling. But the mean C of these 54 was a disappointing 2.8. 

An impressive 2013 growing-season-long video of Tomlinson can be found here. 

References:

Bowles, M. and J. McBride. 1996. Report to the Illinois Department of Natural Resources, The Morton Arboretum, Lisle, Ill. Click here.

Bowles, Marlin and Michael Jones. 2003. Twenty-five Year Trends of Chjange in Prairie and Wetland Natural Areas in the Chicago Region of Northeastern Illinois. Illinois Department of Natural Resources. Click here.

Ellis, James L. and Kevin J. Wolz. Vegetation of Tomlinson Pioneer Cemetery Prairie Nature Preserve, Champaign County, Illinois. Transactions of the Illinois State Academy of Science (2018) Volume 111, pp. 11-16 received 12/1/15 accepted 3/4/18. click here. 

Universal FQI. The FQI Database used in this post was: Taft, J. B., Wilhelm, G. S., Ladd, D. M., & Masters, L. A. 1997. Floristic quality assessment for vegetation in Illinois, a method for assessing vegetation integrity. Westville: Illinois Native Plant Society. Click here. 

For other posts on monitoring and studies, click here.

Acknowledgements

The authors of the scientific papers deserve principal credit. There would be no solid basis for evaluating this preserve without their important work. Credit goes to Marlin Bowles, Jenny McBride, James Ellis, and Kevin Wolz. There should be more funding for such work. 

Burns and management of Tomlinson are to the credit of the Champaign County Forest Preserve District. 

Thanks to Clio (https://theclio.com) for the burn photos. 

Thanks to Matt Evans for the growing season photos.

Index to Posts on Prairies

Click here for the Master Index to (most significant) Posts

Posts on Prairies:

What is a Grade A Prairie?

          Escaping from Too Much Tall Grass - the next frontier  

Wet-mesic Prairie: Time for a Rebirth?

Are they Hypotheses? or Myths?

Yellow Stargrass Restoration

Prairie Lily Restoration

A Prairie Orchid Reveals Its Secrets

Somme Prairie: from two acres to seventy

Grant Creek Prairie needs Friends Fast

Morton Grove Prairie Rises Again

Scything and mowing for biodiversity

Index to Posts about Biodiversity History and Ideas

Click here for the Master Index to (most significant) Posts

Posts about Biodiversity History and Ideas:

Some History of Biodiversity Conservation 

A Biodiversity History Timeline

Grand Narrative of Planetary Restoration - a vision 

Chicago Wilderness region History tidbits from about 1996 to 2016 

Histories and Comparisons of state Nature Preserve and related programs (by a professor)

Are they Hypotheses? or Myths?

How the Friends pursue Our Mission

49th Anniversary of North Branch Restoration Project

Dense dark forests are modern phenomenon

          A Needed Revolution? 

49th Anniversary of North Branch Stewardship

On August 6, 1977, a dozen generous and happy people launched the North Branch Restoration Project. It inspired similar work at hundreds of sites, engaging hundreds of thousands of people, a history that continues to expand today.  

That first day, a dozen of us gathered seeds of smooth phlox on unprotected land adjacent to Somme Prairie. August is a strange time of year to start. But it was the first weekend day after we finally got the approval of Forest Preserve staff to do this work - initially cutting small brush and planting locally gathered seeds.

There seem to be no photos of day one. But the two photos below shows us the following Saturday planting those seeds in Miami and Wayside Forest Preserves.  

We planted those precious, hard to find seeds one at a time.

The seeds did great, but it took five years for them to grow big enough to flower. 

We were initially called the North Branch Prairie Project, and the site that inspired us was the little 2-acre Grade A prairie at Somme. But it didn't look like this when we first saw it. 

It was full of shrubs and trees, with the quality areas scattered among them.

Bit by bit we cut brush and burned, and the quality area increased. 

Another natural area that inspired us was the rich Bunker Hill oak woodland. But it took us a while to learn (and then to convince others) that it too deserved fire, invasives control, and other stewardship. 

In time we wistfully removed "Prairie" from our name and became the North Branch Restoration Project. 

Every North Branch site - indeed every stewardship site - deserves a good curating and presentation of its history. These treasures and the work to restore them are important heritage.

Perhaps more history would be worth revisiting (and a bit more celebration planned) on the 50th North Branch anniversary, a year from now. 

For more fragmentary bits of this history on this blog, check out Nine Stories, After the Miracle, and the Index to Posts on Collaboration and the Human Community.

Parasite and Partner: the leafless, rootless Dodder

As we put this parasite into our seed mixes, we remember regularly getting alarmed alerts from summer visitors to Somme Prairie Grove: "There's some kind of parasite taking over! Can anything be done?!?"

Be calm, friends. We plant it. 

It's a great partner in restoration of ecosystem health and biodiversity. 

At first we see just a few pale vines, searching around:

Then they start to encircle and cling:

And soon, it's clearly having an impact:

One of the common names for this species is "love vine." But it does not just embrace. It kills, or at least severely depletes.

Those coils are not strangling. They're sucking out nutrients.

It may cover large areas of prairie or savanna:

It thrives where there's heavy domination by one or a few aggressive species - tall goldenrod, woodland sunflower, saw-tooth sunflower, or mountain mint. It seems to be able to reduce their dominance enough that diverse species can then be seeded in. 

It's an amazing plant. When a seed falls to the ground, it waits until the following spring, and at just the right moment, it germinates. But it does not put down a root, and it never makes a leaf. Instead, it uses the energy packed inside that seed to reach out for the stem of a victim. 

Is "victim" the right word here? One night on Jimmy Kimmel's late-night show, Jimmie began with the words, "Hi! I'm Jimmy Kimmel. I'm the host, and you're the parasites." Botanical humor strikes again.

But indeed, perhaps "host" is the better and more objective word.  

Though, as you see the assault continue, it can be hard to be coolly objective.

We see two species of dodder at Somme. Most of the photos here are of Cuscuta gronovii, common dodder. We also see rope dodder, Cuscuta glomerata, shown below:

Below, the main victim of common dodder is saw-tooth sunflower:

Or below: on woodland sunflower and tall goldenrod: 

If a host invited me to something and I suspected to be treated this way, I don't think I'd go. 

And this is still early on. Soon the green will bleach out of the host's leaves. The dodder will start to make buds, then flowers, and then seeds. 

When they emerge, its flowers will look like this:

Dodder often leaves other species unaffected, but the aggressive species had been so dominant, that there's now mostly bare ground. 

We broadcast the seed of diverse species into these bare spots, and our impression is that they do pretty well. The monoculture of aggression is history. We should do more careful studies. Perhaps others could do so as well.

Acknowledgements:

Thanks to GoBotany for the close-up photo of dodder flowers. 

For other posts on controlling invasive plants, click here.

For a Master Index to Posts, click here.

These Two Sites Had Been The Same

A few hundred feet apart, these two areas are linked. 
Formerly pasture, both had been "protected" conservation land that had been invaded by buckthorn. 
The site on the left (below) was on its own. Buckthorn is nearly all that’s survives. For that patch, the conservation goal had failed. 

The site on the right has received restoration management that has allowed it to keep and expand its biodiversity. 

                  Nature Left Alone                                Nature Conserved and Restored                                                  

In the early days of biodiversity conservation and restoration, some people argued that it would be wrong to "play God" by meddling with nature on land set aside from human manipulation. "Leave it alone!" they insisted. We don't much hear that argument any more. The scene below is partly why.

                                                Nature Left "to Take its Course"

Compared to cared-for land nearby, this scene is shocking. Buckthorn has now replaced nearly all other plants. The birds, pollinators and other animals are also gone. We hadn't found time to get to this opening that survived among the advancing brush. Indeed, we lost a few more such patches also. Restoration is work and takes time. We remember such natural vegetation as purple milkweed here where young buckthorn now rules, as well as Kalm's brome and big bluestem.

In 1977, when restoration began at Somme, the land was fallow former farmland. The areas that originally seemed most worth our help were former pasture openings among young trees and brush. In them, though most original plant species were gone, some "prairie species" survived, a few in one opening, different ones in others.   

The land now called Somme had then been set aside as "Cook County Forest Preserves" decades earlier. Would more trees be best here? We knew that the Forest Preserve concept also embraced prairies. The charter of the Preserve District expressed its goal: 

"to restore and restock, protect and preserve ... such lands together with their flora and fauna as nearly as may be, in their natural state and condition."

As the science of ecology developed, it was determined that the natural state of the Somme preserves included prairie, savanna, oak woodland, and wetland. All needed and deserved stewardship.

But maples, box elders, dogwood, and buckthorns had been gradually increasing around the edges of the relatively-stable, higher-quality prairie and savanna openings ... and in the formerly-grazed woodlands as well. Seed blown on the wind or carried by birds was successfully able to complete with existing "old field" vegetation where the turf of pasture plants was weakest. 

Our innocent goal back then was to expand the openings that contained the rare plants and spread seed from each to each (and other surviving remnants nearby). We sought to restore the diversity that, with occasional burns, would resist invasion by brush and malignant weeds. We cut, burned, and gathered and sowed seed. There were challenges of many kinds, ecological and bureaucratic. A few openings, like the one above, were lost to brush. But bit by bit, most were expanded and enriched until, after 49 years of work and ecosystem self-healing, they looked like the photo below:

                                                Nature Restored and Conserved

Here the plants in bloom include wild quinine (white), prairie coreopsis (yellow), and butterfly milkweed (orange). Visible by foliage and soon to bloom are lead plant, purple prairie clover, dropseed grass, and early goldenrod. Earlier this year we saw here shooting star, violet wood sorrel, bastard toadflax, wood betony, Seneca snakeroot, prairie violet, and many others. Each week it's different, throughout the growing season.

The animals thrive among them. Birds seen and heard in the area of this photo include orchard orioles, eastern kingbirds, indigo buntings, ruby-throated hummingbirds, kestrels, and another long list. Rare butterflies and other pollinators abound. Fungi, bacteria, and likely hundreds of species of rare micro-organisms are part of the still-recovering ancient ecosystem here. We still fight such invaders as teasel, crown vetch, and reed canary grass in some areas. It's not quick. But successes give us confidence and inspiration. 

Bless the hundreds of people who have done and are doing this good work. We remember that it could all have been lost. We are inspired by hope for its future, including the still neglected areas ... as we can get to them. 

Endnote

These two photos were taken a few days apart. The first shows a former "old field" opening on the edge of former prairie and savanna near the north edge of Somme Woods. Despite dramatic improvements in most areas, these 255 acres still have scores of acres waiting for help.

The second photo shows a formerly-similar opening on the edge of now-restored prairie and savanna in the 85-acre Somme Prairie Grove, where restoration started much earlier.

References

For an Index to Posts on Controlling Invasive Plants, click here.