This summer we had completed the construction of the fish passages on the Rio Caprionero (basin of the Volturno River) and on the Rio S. Maria (basin of the Biferno River). These works are fundamental to overcome the barriers that man has built in the river beds and which prevent or make it more difficult for native trout to reach the breeding sites. We will observe the full effectiveness of these works only during the reproductive period, but we are already seeing the first results.
In particular, on the Rio Caprionero, we intervened to eliminate an artificial waterfall by means of a ramp made of cyclopean boulders and stones and we placed current deflectors in an artificial stretch to allow the trout to colonize the upstream area and restore the natural river continuity. While waiting for the large Volturno spawners, during the seasonal capture activities for monitoring the health of the populations and for genetic analysis, we have already verified how the juvenile stages and the small resident trout are already using the ramp to move. Even some individuals are stationed in the artificialized section in which, before our intervention, we had never caught a fish.
Do you remember that we told you about the difference in colors and morphology of the resident fish of the Rio Caprionero compared to the reproducers that go back from the Volturno? Well, now here is a detail of one of the resident adults captured in the stretch object of the intervention: what colors its livery!