Since the fall of the Eastern bloc, both Ukraine and Romania have seen their populations shrink. Driven by rural to urban migration, low fertility rates, and substantial emigration, the depopulation in the Danube Delta region has opened up large areas to rewilding efforts. With a history of irrigation and altered river dynamics, restoration and reintroduction of large, landscape-shaping mammals has led to an exciting new wildlife recovery.
By Pernilla Hansson

On the border between Ukraine and Romania lies the mighty Danube Delta, Europe’s largest remaining natural wetland area.1 Representing the outflow of the river Danube into the Black Sea, the area is surprisingly undestroyed,2 which makes it a valuable place in Europe, the continent with least undisturbed nature left.3 It harbours the largest numbers of fish species in Europe, notably four species of endangered sturgeon.4 Constituting an important part of the great Palaearctic-African flyways which connect birds migrating between Europe and Africa, it is also home to many water birds.2
Although parts of the delta retain much of their naturalness and it is one of the least populated areas in Europe,4 it has still seen considerable human disturbances. Dams, polders, and roads were built during the 20th century to claim the land for agriculture and irrigation. Of the three arms of the Danube, only one was left in its natural state, while the other two were straightened.2 Around 80% of the original floodplains have been lost to drainage, as well as navigation and flood prevention.1 The negative consequences of trying to “tame” the wilderness of the region are numerous, such as degraded ability to mitigate flooding,5 deteriorating water quality, and biodiversity loss. Much of the river-taming infrastructure has now been rendered obsolete and left dilapidated in the landscape.6
During the times of the large development that created these structures, Ukraine and Romania were part of the Eastern bloc, and their populations were on the rise. It is therefore no surprise that there need for more agricultural land to support their populations. However, after the dissolution of the Soviet Union and the revolutions in 1989, both countries saw a quick turn to population decrease. Between 1990 and 2019, Romania and Ukraine experienced a population decrease of approximately 18% and 15%, respectively. Although total fertility rate (TFR) is far below replacement level (currently 1.62 in Romania and 1.44 in Ukraine), the quick turn in population was largely caused by strong emigration to other countries.7 In Ukraine, the rural populations had already been decreasing since 1959 as many young people moved to regional centres with prosperous economic development and work opportunities. The depopulation trend continued with emigration to western countries after 1990, which added to the decline in natural reproduction to further decrease the population of the country.8

In Romania, a similar trend of rural to urban migration started in the 1960s, when private property was abolished.9 Although the desire to emigrate out of the country increased during the last turbulent years of the socialist regime, emigration was tightly controlled by the authorities.10 During that regime, there was also a history of active interference in population matters. In 1966, a pronatalist decree was announced, banning abortions (formerly the main means of birth control in the country) and imposing a tax on single people and childless couples. While initially TFR doubled as a result of these measures, fertility continued to decline in subsequent years, and in 1984 it passed below replacement level. After the 1989 revolution, abortion was once again legalised,11 and migration to western countries exploded. This was partly due to the previous block on emigration, but also the deindustrialisation that was taking place and the failure to create new jobs. For many individuals, this left emigration as one of the only economic possibilities.10
The regions surrounding the delta have all experienced decreasing populations, on both the Romanian12 and Ukrainian side,13 and the delta has seen large land use changes as well as rural exodus.4 Large areas of agricultural land were abandoned, often in a deteriorated state but with excellent opportunities to revive the natural landscape. As both countries are projected to continue decreasing in population,7 more land can be expected to open up for rewilding efforts.

In recent decades, countries in the region have realised the potential benefits of restoration of the Danube River and its surrounding area. At the beginning of the new millennium, Ukraine, Romania, Moldova, and Bulgaria all signed an agreement known as the Lower Danube Green Corridor, to protect around 1 million hectares of the Danube area, as well as restoring 224,000 hectares of floodplain. The main aims of this huge restoration project were to restore biodiversity, reduce flood risk to nearby settlements, and protect nature-based services. In the first decade they reached their goal for protected land, with around 1.4 million hectares under some form of formal protection.5 The whole of the delta, in both Ukraine and Romania, is under coordinated management as the Danube Delta Biosphere Reserve, in which core areas of strict protection and natural management, connected to each other through corridors, are surrounded by areas where agricultural activities are constrained to ensure sustainable landuse.4 Together with other protected areas, the biosphere reserve covers the whole delta.

The restoration of this Danube area was first spearheaded by WWF, followed by Rewilding Europe in 2013, an organisation that works to restore environments in Europe and reintroduce lost species. The first restoration project area was Tataru island. Tataru island is located on the Ukrainian side of the Danube Delta, and until 50 years ago, that side of the delta remained largely intact. However, in the 1960s, many irrigation dykes were constructed, and wetland was converted into areas for forestry and agriculture. For a while the crop and wood production was economically viable, but the ecosystem deteriorated, creating many problems; fish populations declined as a consequence of the loss of spawning areas; the inner lakes became salinized and unsuitable for human use; salts built up in the soils during summer but were not washed away during spring as flooding was prevented; and the now unfiltered river water carried sediments to the Black Sea, causing hypoxia of the sea bed. Ultimately, the attempts to conquer the area, which initially seemed promising, had backfired, causing more damage than the initial economic gain.
In 2003, WWF and the local forestry authority removed 6 kilometres of dykes, which allowed natural flooding to once again take place on the island. The re-establishment of this natural process led to freshwater retention in the centre lakes and deposit of sediments on Tataru island, facilitating island growth. Two years later, a herd of grey cattle was released onto the island to take the place of former grazing animals that had been hunted to extinction. After only 4 years, the herd had grown large enough to supply the local community with meat.14 Complementary release of 10 semi-wild horses was carried out in 2019 by Rewilding Europe.2 Now several valued species of birds thrive on the island, including white-tailed eagles and pygmy cormorants, and the inner lakes provide spawning grounds for young fish.15
The nearby Ermakov island suffered a similar fate during the 1970s, but the efforts to create viable agricultural lands failed and the island was left barren. Following the success of the Tataru island restoration, the WWF removed a section of dyke from Ermakov island so that it too became reconnected to seasonal flooding.14 Rewilding Europe continued the restoration through releasing konik horses, that are to take the role of the extinct wild Eurasian horse Tarpan, and water buffalo in 2019.5 The large equids and bovines are important shapers of the ecosystem, opening up reed beds, creating pools and puddles valuable to insects and amphibians, as well as distributing seeds to new locations. Ermakov island is now one of the richest biodiversity areas of the Danube Biosphere Reserve.6
Of the many bird species in the area, totalling over 300, two that have been singled out for rewilding purposes are the Eagle owl and the Dalmatian pelican. Eagle owls were once found across all of Ukraine, but are now restricted to small regions in the north and east. Their decline has mainly been attributed to eradication campaigns and collisions with power lines. The first juveniles have now been released in the area, to fill in a gap in the trophic chain and aid in controlling the large rat population of the delta that otherwise destroy the nests of many birds.6

The Dalmatian pelican is an iconic species and indicator of ecological health, but has historically declined due to human activities, be it habitat loss, collisions with power lines, illegal hunting, or destruction of breeding colonies to prevent competition with fishermen. Efforts to help the species recover include making the power lines more noticeable to birds in flight, and the creation of artificial floating platforms for breeding and roosting, which will protect the nesting sites from water level changes.2 The Danube Delta is a key site for the global conservation of the species, as it hosts an estimated 300-350 breeding pairs.5 As tourism in the region increases, local boatmen are trained to recognise and understand this important species (as well as how to approach them without harming them), to further the economic security of the region and instil a sense of pride.

Rewilding is not just carried out directly in the Danube Delta, but also the surrounding ecosystems. This includes the region’s steppe environment, which was once inhabited by large herds of herbivores, such as wild horses, saiga antelope, aurochs (an extinct European bovine), and the Asian wild ass kulan. The large herds would shape not only the steppe but also the delta landscape, as they would migrate to the delta wetlands during times of severe drought or intense cold, creating a connectivity between the landscapes. Human interference in the form of agricultural development caused the disappearance of the large herbivores from the region, effectively cutting the natural connection between the wetlands and steppe.
The largest remaining part of the Eurasian steppe found in the region is the Tarutino Steppe, located approximately 50 km north-east of the delta.6 This region of Ukraine has seen a continuous decrease in human population, leaving behind land suitable for rewilding.13 In this ecosystem, the focal rewilding species is the kulan. This subspecies of Asian wild ass once ranged from the Mediterranean to the east of Mongolia, but their range has decreased more than 95% during the last two centuries, owing to overhunting and habitat loss. In the Danube area they have been missing for hundreds of years, but in 2020 a herd of 20 individuals was translocated to the Tarutino steppe. This reintroduction is the start of a long-term programme which aims to establish a free-roaming herd of 250 – 300 individuals in the delta region by 2035. The kulan could form an additional prey species for predators such as wolves and golden jackals, and their grazing will keep grass length on the steppe short, which not only mitigates wildfire risk, but also benefits endangered steppe rodents, such as the souslik, dependent on open grasslands.6

The people living in the Danube Delta region are often socioeconomically vulnerable, and its rewilding provides new sources of income, not only through tourism, but also through sustainable harvesting of revitalised plant and animal populations. Rewilding Europe hopes that successful restoration will inspire people in other regions to view rewilding as a tool to improve their quality of life.4 While previously built infrastructure ultimately had a negative impact on the local inhabitants, especially through the decline of fish stocks,6 the new rewilding projects have reversed this.
Anticipated further decrease in human populations in Romania and Ukraine will ultimately be beneficial to the wilderness in the region, as more abandoned land can be restored to former ecosystem functions.
Further restoration plans for the Danube area have already been set in motion both in Romania and Ukraine, and also in neighbouring Moldova. Nature-based economic incentives are being further developed to raise the living standards of the people that remain. The tourism infrastructure is being expanded, with new wildlife observation towers and hides, and the preparatory work has been done to create a company for local fishermen, with a focus on culturally-themed angling.5
The restoration of the Danube Delta was greatly aided by historically low levels of human interference, but in areas with anthropogenic influence, recently decreasing human numbers have meant less land under human pressure. This facilitated the removal of dilapidated infrastructure from foregone eras, as well as allowing for large scale reintroduction of lost species. Ultimately, as humans retreat from regions previously exploited, nature can, with some help, quickly recover and form thriving and biodiverse communities.
See the past entries in our “population and rewilding” series:
Fewer People leads the way to rewilding in Portugal
Restoring Abandoned Land in the Oder Delta Gives New Opportunities for Wildife in Germany and Poland
Fewer People = More Wild Nature in Croatia’s Velebit Mountains
To learn more about the connection between rewilding and decreasing human numbers, read Dave Foreman’s book Manswarm: How Overpopulation is Killing the Wild World and explore Rewilding Earth’s excellent podcast series.
References:
- Lower Danube Green Corridor agreement [Internet]. Danube +: WWF staff; Accessed August 18, 2020. Available from: http://danube.panda.org/wwf/web/search/details.jsp?pid=41
- Rewilding Danube Delta [Internet]. Nijmegen: Rewilding Europe; Accessed August 18, 2020. Available from: https://rewilding-danube-delta.com/
- Navarro LM. Rewilding abandoned landscapes in Europe: Biodiversity impact and contribution to human well-being. University of Lisbon, Department of animal biology (Doctorial thesis) 2014.
- Rewilding Europe. Danube Delta [Internet]. Nijmegen: Rewilding Europe; Accessed August 18, 2020. Available from: https://rewildingeurope.com/areas/danube-delta/
- Allen D, Schepers F. Rewilding Europe: Annual Review 2019. Nijmegen (NL): DPN Rikken print; 2020. p. 84-85. https://www.rewildingeurope.com/wp-content/uploads/publications/rewilding-europe-annual-review-2019/
- Endangered Landscapes Programme. Danube Delta [Internet]. Endangered Landscapes Programme; Accessed August 18, 2020. Available from: https://www.endangeredlandscapes.org/project/danube-delta/
- United Nations, Department of Economic and Social Affairs, Population Division (2019). World Population Prospects 2019. Online Edition.
- Karachurina L, Mkrtchyan N. Population change in the regional centres and internal periphery of the regions in Russia, Ukraine and Belarus over the period of 1990-2000s. Bulletin of Geography. Socio-economic Series. Vol. 28, 91-111. 2015. DOI: http://dx.doi.org/10.1515/bog-2015-0018
- Otovescu C, Otovescu A. The Depopulation of Romania – Is It an Irreversible Process? Revista de Cercetare și Intervenție Socială. Vol. 65, 370-388. 2019. DOI: https://doi.org/10.33788/rcis.65.23
- Horváth I, Anghel RG. Migration and Its Consequences for Romania. Südosteuropa. Vol 57, 385-403. 2009.
- Muresan C. Changes in the demography of Romania. Past trends (1948-1994) and future perspectives (1995-2030) (in French). Population (French Edition). Vol. 51, 813-844. 1996.
- Population on 1 January by age group, sex and NUTS 3 region. Luxembourg: Eurostat; Accessed August 18, 2020. Available from: https://appsso.eurostat.ec.europa.eu/nui/show.do?dataset=demo_r_pjanaggr3&lang=en
- City Population. Odesa Oblast [Internet]. Thomas Brinkhoff; City Population; Accessed August 18, 2020. Available from: https://citypopulation.de/en/ukraine/admin/51__od%C4%97sa_oblast/
- Bringing life to the lower Danube – a real success story for WWF in Ukraine [Internet]. WWF; Accessed August 18, 2020. Available from: https://wwf.panda.org/?181581/BringinglifetothelowerDanube
- Tataru Island [Internet]. Danube +: WWF staff; Accessed August 18, 2020. Available from: http://danube.panda.org/wwf/web/search/details.jsp?pid=53
Map data: UNEP-WCMC and IUCN (2020), Protected Planet: [The World Database on Protected Areas (WDPA)] [Internet], [________], Cambridge UK: UNEP-WCMC and IUCN.
“Anticipated further decrease in human populations in Romania and Ukraine will ultimately be beneficial to the wilderness in the region, as more abandoned land can be restored to former ecosystem functions.”Sounds very optimistic. But I read about total deforestation in Western Ukraine. How will this affect the further situation?
The future situation will definitely depend on the choices of the respective countries. In general, a lowering human population will mean a lessened demand on land and resources, but other factors, such as economic interests, can often have a strong impact on what happens to those natural resources. Ultimately, it depends on if the country takes the opportunity to restore the former wilderness, and currently, the deforestation of Western Ukraine seems to suggest the opposite. While the deforestation in itself is seemingly not currently affecting the Danube Delta, it is a worrisome trend.