Restoring the Nachusa Grasslands
- Aug 21
- 7 min read
Dear Reader,
In April 2026, I visited the Nachusa Grasslands, located ~2 hours away from Chicago, Illinois, as part of a study tour during a science journalists conference. Of the options listed, including a wastewater treatment plant and a sand dune reserve, something in the title made me select this field trip: bison reintroduction!
The description had me hooked: The tallgrass prairie, once the defining ecosystem of Illinois, has been reduced to a few thousand acres amid agriculture and development. At The Nature Conservancy’s Nachusa Grasslands, volunteers and scientists are working to change that, planting native seeds and reintroducing ecological processes like fire and grazing across 4,000 restored acres. Since 2014, a growing herd of American bison has returned to the prairie, shaping plant structure and transforming animal communities from beetles to sparrows, alongside over 180 bird species and endangered wildlife like Blanding’s turtles.
This was my first-ever trip to the United States, and I couldn’t miss the chance to see bison. I dug into the history of bison herds across the American landscape, and at Nachusa, I heard the story of what inspired them to restore these prairie landscapes, and what bison reintroduction entails.
With this essay, Geosophy has expanded to three continents — Asia, Africa, and North America. When I started the newsletter, I thought I’d mostly cover the Indian subcontinent. Yet I’ve had the chance to travel widely, as part of my work, and explore landscapes as diverse as an inselberg-fortress in Sri Lanka, the volcanoes in Indonesia, the limestone reserves in the Philippines, the topography of Thailand, the coastlines of South Korea, and the mosaic landscapes of Kenya. Here’s to more landscape stories from far and wide!
As always, thanks for trailing along,
Devayani.
Acre by Acre: The Story of Nachusa Grasslands
Sometime in the 1970s, Dot and Doug Wade were driving through the Illinois countryside and heard the whistling call of an upland sandpiper — for non-birdwatchers, the sandpiper is a buff-brown patterned shorebird. When they pulled over, the landscape stretching before them was heavily grazed pasture, yet the dominant plants were prairie or grassland varieties.
The word ‘prairie’ derived from the French word for meadow, represents temperate grasslands, with deep-rooted, native grasses and wildflowers. It can be used synonymously with grasslands (see the #37. Landscape Lexicon: Grasslands). Pasturelands, on the other hand, are managed and grazed agricultural patches with shallow-rooted, often non-native plants. Prairies or natural grasslands often have a higher plant diversity and are more resilient to wildfires and droughts than pasturelands, with quick-growing, not-too-diverse plants.
With their enthusiasm for prairies, Dot and Doug explored the landscape further. To their surprise, they found seeps, springs, sedge meadows, a fen and oak savannas — relics of a former prairie landscape. Could such a landscape hold potential for restoration and conservation efforts?
A few years later at a conservation meeting, one key question was raised: should conservation direct its resources toward larger landscapes with lower-quality habitat, where animals could thrive, and ecosystem processes could function? Or should they focus only on the smaller, high-quality sites?
Nachusa’s landscape seemed to be the perfect site to explore the first question further. In 1985, the Nature Conservancy began purchasing little parcels of land. One year later, they owned 397 acres that were named the Nachusa Grasslands. Forty years on, these prairie restoration efforts have expanded to a 4112-acre habitat home to over 700 native plant species, over 245 bird species, 280 bee species, and a thriving bison herd.
Prairies, then and now
Over centuries, prairies were diverse habitats of grasses, herbs, and sedges, grazed and trampled by native species like bison, pronghorn antelope, deer, and elk. Of these species, the bison was a keystone species — it played a critical role in maintaining the prairie ecosystem. Native Americans lived off the land, hunted these species for their hides and built teepees of prairie grass. The song, ‘Colors of the Wind’, from the Disney film Pocahontas, beautifully captures the connection of the native people with their land and its denizens, with hauntingly ironic lyrics about ‘savages’ and ‘owning land’. (If you haven’t heard it, I would highly recommend listening to it, or better still watching the animated version from the film).
In the 16th century, when the first colonizers reached North America’s vast grasslands, they saw enormous herds of bison — later estimates say there were over 20-30 million bison. The Spanish nicknamed them ‘crooked-backed oxen’, and wrote of how the herds stretched as far as the eye could see, across a vast, flat, featureless landscape, in numbers that were impossible to count. As the early settlers and the newer arrivals expanded westwards in search of minerals and oil, they hunted the bison ruthlessly. By 1889, the million-strong herds were reduced to a mere 541 survivors! Along with the bison, the native tribes were also hunted — their lands and livelihoods appropriated, with railways crisscrossing their settlements and sacred sites.
With the natives near-exterminated, the new government offered parcels of the arid, flat land to settlers looking for a new life. As the prairie was put under the plough, the landscape was altered beyond recognition. With mechanised farm equipment and the introduction of pesticides to grow corn and other crops, the soil carbon and nitrogen cycles were affected. The once-fertile grasslands were overgrazed and overtrampled by cattle, and native prairie vegetation gave way to pasturelands. With shallow roots, pasture grasses are a poor defence against the region’s dry winds and rainfall, and the region has experienced several droughts, dust storms, and a stripping away of the sparse topsoil.
Today, most of North America’s prairies have vanished — habitat loss estimates range from 50-98% of historical acreage — along with numerous native grass species and wildflowers. As the importance of grasslands in sustaining wildlife, capturing carbon, conserving soil, and supporting food systems is realised, several restoration efforts are underway.
Of Prairies and Ponds: Restoring a Landscape
Without tall grasses, the prairie’s ability to capture rainwater and create a patchwork of intermittent wetlands is lost. That’s why the discovery of seeps and springs at Nachusa was so exciting — they held promise that the prairie landscape could be restored.
The restoration was a laborious process of weeding out the non-native species, creating seed banks and nurseries for the native varieties, studying their seasonal rhythms to better understand when to start replanting, and learning how to use fire to maintain the ecosystem. For this, Nachusa grasslands rely heavily on volunteer efforts, seasonal community drives for replanting and an ever-rotating mix of scientists who want to study or monitor the grasslands, and the species that they support.
The restoration work at Nachusa always envisioned re-establishing the bison herds. After all, bison grazing and their hoof-and-horn behaviour shaped ancient prairies. The way bison move through the landscape, prune the grasses, stamp and paw at the ground helps biodiversity flourish, from wildflowers and plants that host insects, to creating depressions for ephemeral amphibian habitats! A 30-strong herd from Wind Cave National Park in South Dakota were brought to Nachusa. Today, through careful bison stewardship, which includes minimal veterinary care, monitoring herd dynamics such as the ratio of males to females, and bringing in new males to ensure genetic diversity, the herd has grown to 100+ individuals.
When I visited, the staff were excited about the 100th research paper published on the Nachusa Grasslands, ranging from grassland plant diversity to insect diversity, and some document how bison behaviour has changed the soil ecology — these insights could serve other restoration projects, not just in the States, but elsewhere in the world.
Stewardship: Land, Wildlife & Forest
Of the conservation lessons I learned at Nachusa, the term ‘stewardship’ stayed with me. Stewardship ensures that the criteria for which the resource was granted legal protection continue to be fulfilled.
In the case of land stewardship, appropriate and routine management of the protected land, including invasive species removal, replanting native species, and restoring water and soil, is critical for the land to serve its ecosystem functions. If we consider wildlife stewardship, local communities have long tended to herds of wildlife, culled the weak and old, monitored threats, tracked annual migrations, and served as guardians of a species. Forest stewardship involves carefully managing forest reserves to produce timber, balance extraction and exploitation, track and mitigate the impact of wildfires, and ensure vegetation is diverse enough to support native biodiversity.
World over, some of the most incredible conservation stories are those of community stewardship: more than 400 Indigeneous communities have played a critical role in preserving the Amazon river basin and its tropical rainforests, pastoralists of have long stewarded Mongolia’s steppes, Australia’s rangelands have been carefully managed by the Aborigines, Niger’s farmers and herders have been combating the desertification of the Sahel region with restoration techniques, the list goes on.
Closer to home, India’s Bishnoi tribes fiercely protect the Thar Desert’s flora and fauna, especially the blackbuck or Indian antelope (Antilope cervicapra), and the chinkara or Indian gazelle (Gazella bennettii), and as a result, have raised awareness about the rich biodiversity of what’s often considered a wasteland. The Van Gujjars of north India are semi-nomadic pastoralists who herd buffaloes across ever-shrinking, less accessible pastures. As their buffalo herds move across open pasturelands, the herders maintain the water embankments, remove invasive species across pasturelands, and create fire lines through forests to protect the ecosystem for wild creatures, while their buffaloes fertilize the pasturelands with manure.
Good stewardship balances ecosystem functions with the critical needs of biodiversity and human communities. Humans have long been part of natural ecosystems, for better or for worse, and we will continue to be. If conservation initiatives extract humans from the equation, we fail to understand how critically we’re bound to the same ecosystems. Our myopia has already cost us dearly and will continue to do so if we do not integrate traditional knowledge with scientific rigour to tackle the challenges of a warmer, more polluted world of our making.
