Rehabilitating a puddle network

Like all wet environments in Mediterranean France, temporary puddles are declining habitats, facing various threats: drainage practices, or on the contrary permanent immersion, drainage due to improper or inexistant management, etc.

In the La Capelle pond and puddles site, 56% of the Mediterranean temporary puddles are in a bad state of conservation; 10% are subject to deliberate filling, in part or in whole, by the dumping of dredged material: earth, gravel, plant residues, etc.

The presence of amphibians relying on the availability of a quality puddle network, sufficiently dense and inter-related. The network’s disintegration and fragmentation are the main reasons why many community importance species on the site drop in population, including the great crested newt or the western spadefoot toad.

Within the La Capelle pond and puddles site, 80% of the puddles in this network have an insufficient or bad Habitat Suitability Index for the great crested newt, a rather northern species, nearing the limits of its range in the Mediterranean region.

Projects for the creation and rehabilitation of a puddle network are favourable not only to the key habitats that are the Mediterranean temporary puddles, but also to species specific to the territory, such as the great crested newt or the western spadefoot toad. This measure thus strengthens more widely the site’s turquoise infrastructure soundness.

• First, a vegetation analysis shall be performed on 102 puddles in order to outline the allocation and structure of flowery species linked to the habitat “Mediterranean temporary puddles”. This shall allow the definition of a state zero in order to assess the impact of the work on this habitat.
  A hydrological studywill allow to better know the origin and way the puddles fill themselves, to identify the possibly contaminated puddles, etc. This information will prove to be useful in order to determine and size the projects: measuring the slopes, assessing the volume of land to deepen, decontaminating using specific vegetation, etc.
  These preliminary study shall allow to prioritise the puddles, determine which sites are suitable for creating puddles and draft a managerial notice for each puddle.

• The creation and rehabilitation projects shall be carried out according to these managerial notice: deepening or reprofiling the 15 puddles, digging 5 new puddles, implementing selective barriers set to prevent Louisiana crayfish from entering, clearing, waste disposal, setting up shelters and micro-habitats for hibernating amphibians, etc.
  Meanwhile, the land shall be secured using management agreement or ORE contracts (Real Environmental Obligation) on challenging patches sheltering a puddle either created, rehabilitated or sheltering a watering place playing a part in filling said puddles.