Brook chub, Squalius lucumonis (Pisces, Cyprinidae) conservation aquaculture: First attempt at artificial reproduction and larval rearing

Many recovery programs for endangered species rely on the release of hatchery-reared juveniles to support threatened populations or to re-build new ones. In the framework of a conservation plan for the Italian critically endangered fish (sensu IUCN Red List) Squalius lucumonis, artificial reproduction and larval rearing was carried out for the first time. Wild breeders were collected during reproductive period (May-June) by electrofishing from Fosso Corese, a small tributary of Tiber River (Central Italy). In situ stripping of gametes followed by manual fecundation was carried out. Ex situ incubation of eggs and larval rearing were conducted in the hatchery of LESA (University of Tor Vergata). With the aim of producing fingerlings with “wild-like” behavior, a larval rearing technique in a “green water” large volume tank was applied. For the first time, about 400 fingerlings (87 days old) of brook chub were obtained from about 2300 free embryos (17% survival rate). This result is promising as it demonstrates the technical feasibility of brook chub conservation aquaculture, the first step for an in situ-ex situ recovery plan for this species based on reared fingerlings' restocking.