Temperature-dependence of juvenile Black sea bass growth and lipid accumulation determined through lab experiments conducted from September 2021 to February 2022 at UConn Avery Point

Abstract

The northern stock of Black sea bass (BSB, Centropristis striata) has greatly expanded over the past decade, potentially due to warming Northwest Atlantic shelf waters affecting overwintering especially in juveniles. To gather better empirical data we quantified winter growth and lipid accumulation in BSB juveniles from Long Island Sound using two complementing experiments. The data from Experiment 2 are presented here.

The data from Experiment 1 are presented in a related dataset (https://www.bco-dmo.org/dataset/897895). Experiment 2 measured the same traits as Experiment 1 but exposed juveniles to a simulated thermal overwinter profile (October - March) with seasonally varying food rations. Monthly individual length growth (GR) and weight-specific growth (SGR) responded in the direction of seasonal food level changes, showing reduced growth in December-February in a 'Winter dip' treatment, but compensatory growth in a 'Winter pulse' treatment. A 6-month consumption average of 1.7% feeding-1 ('Winter pulse') elicited a mean GR of 0.15 millimeters per day (mm d-1) and SGR of 0.55% d-1, whereas juveniles consuming on average 3.8% per feeding ('Winter dip') had significantly faster GR (0.20 mm d-1) and SGR (0.71% d-1). Growth efficiencies ranged between 15-30% and were inversely related to food consumption.

In both experiments, juveniles disproportionally accumulated lipid over lean mass, with lipid proportions tripling in Exp2 from 4% at 65 mm to 12% at 120 mm.

For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/898012