In our last meeting with the spanish QLA organizers, it was approved an extra line item in order to build an amphibian pond system into the gravel pit. The study that we conducted the previous months, suggested that the red crayfish (Procambarus clarkii) may be a negative factor for the development of amphibians in the gravel pit ponds. Then, we designed a pond system adapted to the gravel pit specific conditions. The design responds to the necessity of avoiding the two survival strategies: excavation and dispersion.
The red crayfish has the ability to bury into the soil when ponds get dried, looking for wet places. To avoid this, the new pond will be covered with an insulating film. This film has a double function: to store more water for a longer time and to set a barrier for the red crayfish when moving towards deep soil horizons.
Another survival succeed of the red crayfish is its high dispersal ability from one pond to another through the soil surface. To avoid the red crayfish arrival to the new pond system, we will set a wired mesh surrounding it. The mesh size will allow the amphibians movement but not red crayfish arrival.
But… why not to build the pond instead of just designing it?