Despite the ecological importance of this river, regarding the control of the black fly we focus only on the different tourist enclaves that it has, since they are places of human concentration in which there is also a favorable habitat for the development of larvae of black fly, especially the spa area of La Fontcalda.
The characteristics of this river, in which the water does not circulate continuously throughout the year, and with areas in which at certain times of the year the water circulates underground, largely prevents the presence of larvae of these insects. of its course. However, adult individuals are detected throughout this territory, which can be attributed to their proximity to the Ebro river and the ability of these insects to travel long distances.
Sampling: the sampling carried out in this area to detect black fly larvae is based on the observation of the macrophytes found in the riverbed, mainly of the genus Nasturtium (watercress), on which they fix on the leaves or Stems the larvae and pupae of the black fly.
Control: it is carried out manually by applying Bti with the help of a backpack where the product is mixed with the necessary water to obtain an adequate concentration of product and a volume of the mixture that allows us to apply the product for a certain time. The little circulating flow as well as the irregularity in the current, alternating areas with surface water with a certain current and areas without current or with underground circulation, mean that the amount of product applied in each case is determined by the application time, which in Points function can vary between 2 and 4 minutes.
