To support the ecological development of the newly created landscape in the recultivated areas, we optimise the habitats and implement various measures to promote biodiversity and species protection. The areas that are created and measures that have been implemented also require ongoing maintenance to preserve them over the long term.

We present some of these measures here.

Ant relocation

More than 100 wood ant colonies have been relocated from pre-mining areas to recultivated areas in recent years. To accomplish this, the colony is carefully excavated, layer by layer, and all materials are collected in separate containers. The queens are individually found by hand and the colony is provided with food after relocation during an acclimatisation period. Observations of relocated colonies over several years show that the ants remain in the recultivated area over the long term, where they spread and reproduce.

Relocation of amphibians

Since natterjack toads and green toads are protected species, thousands of individuals are relocated from the pre-mining areas of the opencast mines every year. They are collected with a dip net or by hand and transported to the resettlement location in tall containers with a cover. In the recultivated area, the tadpoles are released into the existing species protection waters while the adolescents and mature individuals are released into the adjacent dry land habitat.

Beetle banks

Beetle banks are perennial ridges in arable land, two to four metres in width and about 40cm high, encompassing both open ground and flower strips on different sides. These structures promote the diversity of species in fields and meadows since they provide a habitat for insects, which in turn provide food for farmland birds. Additional habitat is also created for ground-breeding birds and small game.

Grazing

Some semi-open areas are extensively grazed as part of the species protection concept for the Hambach opencast mine. Glan and highland cattle now graze on land previously dedicated to large-scale sugar beet and corn production. Their excretions attract numerous insects that, in turn, serve as food for birds and bats, thereby promoting biodiversity. The species protection concept for the Hambach opencast mine comprises around 1,500ha of areas where ecological measures are implemented in some 800ha of mature forests, the conversion of approximately 600ha of open landscape to optimise the food supply and the planting of around 100ha of networking structures.

Flower strips

Today’s flower strips are mostly edge strips and dividing strips in agricultural areas, free of trees and rich in flowering plants. They serve as a habitat for various plant and animal species by offering food, cover, nesting and breeding sites, refuges and overwinter survival sites. Thus they also serve as important habitat networking structures within the agricultural landscape. They are created in recultivated areas by planting native seeds or transferring mown vegetation. Proper care with mowing and spreading is necessary to maintain species-rich flower strips.

Kingfisher banks

The kingfisher excavates its nesting burrow in soil in order to raise its young. Creating near-natural watercourses with scarp faces on the banks is therefore considered the most important conservation measure in recultivation. Elaborate artificial scarp faces and nesting burrows are also constructed where steep banks are not possible but a sufficient feeding territory exists. Sites are monitored and maintained on a regular basis.

Bat boxes

Suitable bat habitats and breeding sites can be created with the help of artificial nesting aids. Flat boxes imitating narrow clefts are preferably installed on buildings.

Round boxes are preferred by species that live in tree cavities. The entrance is located on the bottom of the nesting box. The boxes are checked and cleaned regularly.

Bat roosts

A bank of concrete pipes was installed at the base of Sophienhöhe heights towards Welldorf in the course of dumping and developed as a potential bat roost. Permanent irrigation was installed to create an appropriate microclimate and the opening was sealed except for a bat entrance. Porous concrete blocks were also installed near the entrance as roosts and transparent corrugated sheets were mounted as sleeping areas. The roost is regularly inspected, maintained and the occurring species are recorded in the course of monitoring.

Water body management

Bodies of water, especially ponds and smaller water bodies with highly defined marsh and siltation zones, are of special importance for the ecosystem. They provide habitats for numerous endangered plant and animal species. Proper care is essential to maintain these habitats over the long term. This includes the removal of sludge from ponds and pools, mowing the reed beds, removing growth along the banks, constructing bank walls and weeding the waters.

Hazel dormouse relocation

Since the hazel dormouse is a protected species, hundreds of individuals are relocated from the pre-mining areas of the opencast mines to recultivated areas every year. Hazel dormouse boxes in which the dormice like to build their dreys are set out. While they are sleeping, the little rodents are moved to their new home where they are provided with a second box for their offspring. Monitoring has shown that the relocated animals reproduce well and also spread in the recultivated areas.

Insect hotels

Special nesting aids are also provided for insects: Various nesting aids are combined in an insect hotel so that many inspect species find a breeding area. There are larger boxes for bumblebees and hornets as well as special nesting tubes for various solitary wild bees, digger wasps and other insects. However, two-thirds of all wild bee species in Germany nest in the ground. Providing a breeding area for these species with easy to dig material such as sand or clay under the hotel is therefore important as well.

Small bodies of water

Various species that depend on small bodies of water are promoted in recultivated areas. Most pioneer species such as the natterjack toad and yellow bellied toad are specialists that require temporary small water bodies. Special concrete basins have proven themselves as small bodies of water. They hold water for the longest possible time, even during droughts, and are easy to maintain. A liner is installed along the bottom for larger ponds. Small bodies of water are covered with gratings as protection against aerial predators.

Pruning of pollarded trees

Pollarded trees are ancient elements of our cultivated landscape with high ecological value. Pollard willows were selectively planted in the recultivated areas. While pollard willows used to be common in the region along brooks and in the river floodplains, only scattered specimens remain today. They used to be pruned back regularly to obtain willow withes for basket weaving. Today they are maintained as a defining landscape feature and important habitats for cavity-nesting species such as the little owl.

Nutrient-poor grassland

Nutrient-poor grassland is a community of plants on nutrient-poor sites, usually created by the grazing of originally forested areas by sheep and goats. Such areas have become rare today but offer a habitat for numerous endangered plant and animal species. Nutrient-poor grassland must be mowed or grazed, otherwise the area becomes overgrown and species diversity declines over time. Regular maintenance with mulching, mowing and shrub removal is therefore carried out.

Transfer of mown vegetation

Obtaining seed regionally from native plants occurring locally is sensible to promote local species. Transferring mown vegetation has proven itself as a means of spreading seeds. Donor areas are mowed as seeds mature and the cuttings are collected for distribution on the new seeding sites of the recultivated areas. Species-rich flower strips and fields are thus restored. The maintenance and transfer of flower strips can be combined in the correct cycle.

Nesting aids

Appropriate breeding sites and habitats for birds are created with the help of artificial nesting aids. A large selection of appropriate nesting aids exists since each species prefers different accommodation. Aids for cavity-nesting and shelter cave nesting species as well as hoopoe, barn owl and eagle owl nest boxes and little owl nesting tubes are just some of the options. They can be installed in forests, meadows, gardens or on buildings depending on the habitat requirements. The boxes are checked regularly and cleaned in the autumn.

Meadow orchard management

A total of around 70 meadow orchards and fruit tree avenues with some 150 varieties have been established in the recultivated areas of the Rhenish mining area as special sites and species protection areas to date. This not only contributes to the diversity of species but also preserves the multitude of flavours offered by ancient native fruit varieties for the future. These areas require regular maintenance that is managed using a meadow orchard register created for the purpose.

Partridge shelters

The partridge as a steppe dweller and commensal species is a bird typically found in fields and meadows. This highly endangered bird is very well camouflaged with its brown-grey plumage. It spends the winter in the fields in family groups called coveys. In addition to non-harvesting strips, setting up partridge shelters as dry sanctuaries and hiding places with additional food supplies in winter promotes the partridge in agricultural recultivated areas.

Snake shelters

Reptile and amphibian populations can be documented by setting up and inspecting snake shelters. Snake shelters offer good hiding places and refuges in open areas and along strips of forest. They consist of flat depressions where small cavities are created by wooden slats arranged in a zigzag pattern and covered with panels, boards or rubber mats.

Swallow houses

Swallow houses are free-standing structures with up to 50 swallow nests. Swallow hotels are installed on a four-metre pole and provide breeding sites for large house martin colonies. Special artificial nests to be installed on buildings have been developed for barn swallows. Boards are installed below the swallow nests to keep swallow faeces from soiling the building. They can be colour-matched to the building so the visual appearance is undisturbed.

Floating islands

Artificial, planted islands in recultivated areas promote ecological water body development and, with the near-natural design of vegetation structures, not only help purify the water but also provide habitats and breeding sites for many animals. The base is a tubular frame with structures to hold plants. It floats on the surface of the water and is anchored to the bottom of the body of water. Rather than being in contact with the bottom of the water body, the plants float freely on the water with the structure.

Escarpments

Escarpments have become rare in today’s cultivated landscape. However, they are important as breeding sites and habitats for many animal species. We purposefully create escarpments in recultivated areas where bee-eaters and sand martins as well as wild bees can excavate their nesting burrows and raise their young.

Rock piles

Rock piles provide an important habitat in our landscape for numerous animal species including reptiles, amphibians, insects and birds. Irregular piles of rocks in various shapes and sizes are created in recultivated areas using a dumper and filled with membranes and bark mulch between the rocks. This creates hiding places, breeding sites and frost-proof winter habitats.

Deadwood

Deadwood is an extremely important element of forest biodiversity and provides habitats for many animal and plant species. While recultivated forests are relatively young initially, we actively bring a high proportion of deadwood into the recultivated areas. A suitable habitat for species specific to mature forests, such as woodpeckers and bats, is created this way early on. We differentiate between standing deadwood and deadwood piles.

Bird strike protection

Bird strikes on glass are one of the biggest hazards for our bird populations. Birds cannot perceive the glass. They either see the landscape behind the glass or a reflection of the landscape. A simple, low-cost protective measure helps. Applying adhesive film with various patterns to the glass makes it visible to birds.

Forest soil transfer

Spreading naturally developed forest soil from the pre-mining area on recultivation areas was intended to improve the soil properties and transfer part of the species potential along with microorganisms and soil animals from the mature forest. The effects of this measure have been examined in several studies. While the transfer of species from the mature forest and the improvement of certain soil properties was confirmed, further results have shown that the conditions for development in areas where forestry gravel was spread exclusively are by no means inferior.

Maintenance register

To maintain an overview of the many areas in the Rhenish mining area, a database of all areas subject to maintenance by us has been compiled. This simplifies queries regarding responsibility and the timing and type of maintenance.

Forest edge design

Near-natural forest edges with structural diversity fulfil an important ecological function, both as a habitat and as a networking structure for many different species. We develop and maintain broadly tiered forest edges in recultivation, from the ground vegetation layer to the shrub layer to the stand of trees.

Wild bee nesting mounds

Two-thirds of all wild bee species in Germany nest in the ground. Offering breeding sites for these species in the form of easy to excavate material such as sand or loess is therefore important. Open ground and what are called nesting mounds, made of loosely layered loess and facing south, are readily accepted. Regular monitoring and maintenance ensure that these features do not become overgrown.

Nature-friendly company premises

Measures such as these are not limited to recultivation. Most company premises are defined by extensive paved surfaces and little greenery. Yet designing nature-friendly company premises without interfering with the primary function of performing an economic activity is not that difficult. With the support of the German Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection, the ‘Nature-Friendly Company Premises’ project introduces numerous measures and practical examples that can help companies create a greener environment and infrastructure. These measures have ecological as well as economic advantages and, as a restorative factor, can also have a positive impact on employee well-being. Inspired by this project, we attempted to implement initial ideas on RWE Power premises and in recultivated areas in 2018. A considerable effect can be achieved even with minor measures.

Learn more

Biodiversity strategy

Various sites create high biodiversity! We seize opportunities to voluntarily promote biodiversity in the recultivation.

Animals and plants

Over 3100 animals and around 1500 plants and fungi have already been recorded in the recultivation area - and the number is growing every day.

Research and studies/publications

Together with many partners from the region, we continuously conduct studies in the recultivated landscape in order to constantly optimise the recultivation as part of scientific monitoring.