Rehabilitation of plant and animal biodiversity in South Essonne

Visit of a restoration attempt

As in many regions, the number of plant and animal species in South Essonne and their numbers have decreased considerably over the past 40 years. The main phenomena leading to this decline are, in decreasing order of importance, the modification and disappearance of habitats favourable to species, pollution (including phytosanitary treatments), the arrival of invasive species, The restoration attempt (carried out since 2019) is located on a part of the land (5000 m²) of an old market garden farm dating from the 17th century, at the confluence of two rivers, in an aesthetic setting surrounded by plots not built more or less wooded or treated in green areas. This particular location allows the maintenance of local fauna and flora at the same time as it allows the arrival of regional species not initially present. The method adopted in the restoration attempt aims to correct the phenomena mentioned in the report and to promote the return of regional plants and insects. This choice is based on the fact that plants and insects are key elements in the functioning of natural ecosystems. Their return and development on the spot should therefore naturally be accompanied by those of other animal groups (mammals, birds, reptiles, amphibians, … ) once present but now missing or episodic. 1- Diversification of plots in order to reproduce the types of natural environments on the South-Essonne compatible with the nature of the land: restored river banks, natural meadows, wastelands, orchards, hedges, flowerbeds cultivated consisting only of honey-bearing plants. 2 - Ecological management by annual grassland mowing; No phytosanitary treatment or fertilizer. 3- Manual control of undesirable or invasive plants. Reintroduction by planting or sowing of certain regional species. Creation of roosts, shelters and breeding sites for pollinating and decomposing insects. 4- Since climatic changes cannot be controlled, attempts are made to adapt the site by respecting (and monitoring) new species that have arrived naturally and may be the initiator of a natural change in the local specific composition. Limitation of water losses and watering in flowerbeds cultivated by installation of biodegradable mulch. Results since the beginning of the restoration attempt Since 2019, by limiting ourselves to easily observable organisms, we have been able to count: - 230 species of wild-flowered plants (including 6 orchids) among which 11 are protected and 27 of heritage interest (ZNIEFF determinants). In addition to a hundred cultivated varieties (43 rosebushes). - 154 species of insects (including 26 butterflies) of which 3 are protected and 14 of heritage interest. - 39 species of birds, 37 of which are protected (including 2 raptors), 37 of which are protected and 29 of heritage interest). - 11 mammal species including 3 protected and 2 of heritage interest. - 1 protected reptile species of heritage interest. This year, in addition to the observation of the garden and the discovery of the place and the project, visits (free or commented at the choice of visitors) will highlight four of the five senses commonly used in gardens in relation to other living things: sight (plants, birds, insects), hearing (birds, insects), smell (plants) and touch (plants).