2018 Annual Report Estimating Relative Juvenile Abundance of Ecologically Important Finfish in the Virginia Portion of Chesapeake Bay (1 July 2017 – 30 June 2018)
Virginia Institute of Marine Science
1 July 2017 – 30 June 2018
The Trawl Survey provides crucial data to state, regional, and national fisheries management agencies, including the Virginia Marine Resources Commission (VMRC), the Atlantic States Marine Fisheries Commission (ASMFC), the Mid-Atlantic Fisheries Management Council (MAFMC), and the National Marine Fisheries Service (NMFS). The MAFMC recognizes the juvenile trawl survey as one of the key predictors of Summer Flounder recruitment. Annual indices of juvenile abundance have been generated from trawl survey data for species of key recreational, ecological, and commercial importance in the Virginia portion of Chesapeake Bay. These include Spot, Atlantic Croaker, Weakfish, Summer Flounder, Black Sea Bass, Scup, Striped Bass, White Perch, White Catfish, Channel Catfish, Blue Catfish, Silver Perch, American Eel, and Bay Anchovy.
We completed 1,053 tows in 2017–2018. We collected 435,133 fishes and Bay Anchovy continue to be the most abundant species observed in the survey, accounting for 63% of all fishes collected. Of the target species for which we provide indices of relative abundance, 13 species categories (considering YOY and Age 1+ as distinct categories) exhibited below-average abundance in 2017 – 2018 (American Eel, Atlantic Croaker, Blue Catfish juveniles [all three rivers], Blue Catfish age 1+ [Rappahannock River], Channel Catfish juveniles [all three rivers], Channel Catfish age 1+ [all three rivers], Scup, Spot, Weakfish, White Catfish juveniles [all three rivers], White Catfish age 1+ [all three rivers], White Perch juveniles [Rappahannock and York rivers], and White Perch age 1+ [York River]). Six species categories exhibited average abundances (Bay Anchovy, Black Sea Bass, Striped Bass, Summer Flounder, White Perch juveniles [James River], and White Perch age 1+ [James and Rappahannock rivers]). Silver Perch and Blue Catfish age 1+ (York and James rivers) exhibited above-average abundances this past year.
We changed the index period for the three catfish species, White Perch, and Striped Bass this year. In previous reports, the index period for these species included winter months and we have shifted away from using winter months for operational reasons and uncertainty in their availability to the gear. We examined each species separately using length frequency histograms and determined the recruitment window after these species were fully vulnerable to the trawl gear.
Project Number: F-104-R-22
Tuckey, T. D., & Fabrizio, M. C. (2018) 2018 Annual Report Estimating Relative Juvenile Abundance of Ecologically Important Finfish in the Virginia Portion of Chesapeake Bay (1 July 2017 – 30 June 2018). Virginia Institute of Marine Science, William & Mary. https://doi.org/10.25773/mmjd-zd74