Occurrence of bigheaded carps (Hypophthalmichthys spp.) in the Pearl River Drainage, Louisiana and Mississippi, USA

Two Hypophthalmichthys molitrix (silver carp) were collected in the Pearl River on 6 September 2012 during a natural fish kill in the decommissioned lock chamber of Lock-and-Dam No. 1 located at river kilometer (RKM) 47.5 in St. Tammany Parish, 9.4 km NW of the city of Pearl River, LA. Fish were a male 987 mm TL, 10.9 kg, and a female 1042 mm TL, 12.2 kg. Both fish were age 5. Eight additional silver carp (930-1054 mm TL, 9.1-14.1 kg) and one bighead carp (H. nobilis) (1065 mm TL, 15.9 kg) were collected in the West Middle Pearl River 29 September - 1 October 2015 (RKM 18.9-20.8), 10.5 km E of Slidell, LA (St. Tammany Parish). All specimens were male and ranged 6-9 years in age. A silver carp (age = 7) was collected by a recreational fisher 19 November 2015 in the Pearl River below the Ross Barnett Reservoir (RKM 480) near Jackson, MS. These three collections are believed to represent nonindigenous silver and bighead carp dispersal from the Mississippi River Basin during floods.