May 28, 2014

Return of the wisent: Restoring ecosystems through rewilding

by Bonnie Denmark

On May 17, 2014, more than 250 people assembled on a muddy path in the Southern Carpathian Mountains in Transylvania for a special homecoming celebration. Enter the European bison, or wisent (17 of them to be exact), returning to live in one of the historically core regions for the species after disappearing from the area in 1762.

Wisent release in the Southern Carpathians, Romania, May 17, 2014. (Courtesy of Staffan Widstrand / Rewilding Europe)

Wisent release in the Southern Carpathians, Romania, May 17, 2014. (Courtesy of Staffan Widstrand / Rewilding Europe)

A coordinated effort by Rewilding Europe and WWF-Romania brought the animals from wildlife parks and breeding stations across Europe. This icon of Romanian heritage is the stuff of folktales, place names, coats of arms, and even beer labels, according to WWF Romania’s Adrian Hagatis of the Southern Carpathians rewilding team, and “has never quite disappeared from our minds and souls.” So it is no surprise that the people of the Municipality of Armenis, Romania, gave the wisent a hearty welcome in a ceremony directed by the village mayor and the village priest. Joining them were Romania’s Deputy Minister of Environment, international conservationists, state forestry leaders, local forest workers, farmers, members of hunting organizations, and international media representatives. All in all, a fitting welcome for this ecologically important species.

Known as the “King of the Forest,” the wisent is largest wild land mammal in Europe. It used to roam freely over most of the continent but was hunted until in 1927 only 54 were known to survive, and all of these were in captivity. Once Critically Endangered, the wisent is now listed as Vulnerable on the IUCN Red List of Threatened Species. More will be brought to the Southern Carpathian Mountains over the coming years, and the bison population there is expected to grow to about 500 in ten years. Frans Schepers, managing director of Rewilding Europe, expresses hope that other species can eventually be brought back to the region as well, including “red deer, roe deer, chamois, and the carnivores connected to them.”

Southern Carpathians (Credit: Petr Vodička, Wikipedia)

Southern Carpathians (Credit: Petr Vodička, Wikipedia)

The purpose of “rewilding” is to bring back plant and animal species that no longer exist in an area. The successful reestablishment of native species – or genetically similar species if the original species is extinct – can restore the natural functioning of ecosystems and halt the loss of biodiversity caused in large part by human cultivation of farmland and hunting practices. Large herbivores are critical to the functioning of ecosystems because of their grazing and browsing habits. The Carpathian wisents will be left without human intervention so that they become a natural, wild part of the ecosystem processes.

Many other species preservation and reintroduction programs have been successful around the world. Among them:

  • The reintroduction of wolves has helped restore ecological balance to Yellowstone National Park. The wolves have reduced swelled elk populations, leading to an increase in important plant and animal species along with less erosion of stream and river banks.
  • Restoration efforts have allowed the pronghorn antelope to thrive once again in North America.
  • Lynx were successfully reintroduced into Colorado after dying out there in the 1970s. By 2010, the new lynx population appeared to be self-sustaining.
  • Giant tortoises have been released on islands off Mauritius and on the Hawaiian island of Kauai to control invasive plants and allow native plants to flourish, a job previously performed by extinct native tortoises and flightless ducks. As of 2013, the introduced tortoises were living up to expectations in both regions.
  • Aplomado falcons were reintroduced in Texas and New Mexico. As of 2002, two populations in Texas were self-sustaining and another was on its way to independence in New Mexico.
  • The California Condor and bald eagles have made a comeback in California, thanks to breeding and reintroduction programs.
  • In 1998, 11 Mexican wolves, endangered in the US, were released in Arizona and had grown to around 50 individuals in 2011.
  • The National Wildlife Research Centre in Saudi Arabia has successfully (re)introduced two bird species, the Macqueen’s Bustard and the North African Red-necked Ostrich, a cousin to the extinct Arabian Ostrich.


Learn more about rewilding in Ross Primmer’s article, Improving ecosystems through rewilding, EHS Journal, December 9, 2013.

For more about rewilding projects, see Daniel Cossins’ article Where the wild things were in The Scientist, May 1, 2014.

Read about the Northern Jaguar Project in our module Tracking Endangered Jaguars with Sergio Avila.

Written by

Bonnie Denmark holds an MA in linguistics and teacher certification in English, ESL, and Spanish. She has devoted her professional life to educational and accessibility issues as a computational linguist, multimedia curriculum developer, educator, and writer. She has also worked nationally and internationally as a language instructor, educational technology consultant, and teacher trainer. Bonnie joined the Visionlearning team as a literacy specialist in 2011, assisting the project by developing comprehension aids for science modules and creating other STEM learning materials.

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