TY - JOUR

T1 - Lipid allocation in late-stage barnacle larvae from subtropical and temperate waters

AU - Leal, Ines

AU - Bohn, Katrin

AU - Hawkins, Stephen J.

AU - Jenkins, Stuart

AU - Flores, Augusto A. V.

AU - Tremblay, Rejean

PY - 2021/3/4

Y1 - 2021/3/4

N2 - ABSTRACT: The transition of planktonic late-stage barnacle larvae to a benthic life requires enough energy to power settlement and metamorphosis, and may be compromised by food limitation during early ontogeny. We carried out a comparative study to better understand the larval physiology of space-monopolizing barnacles exposed to contrasting regimes of primary productivity: Chthamalus bisinuatus under a meso-oligotrophic regime on the southeastern coast of Brazil, and C. montagui under a highly productive regime on the southwestern coast of the British Isles. We used an index based on lipid composition—the triacylglycerol (TAG) to phospholipid (PL) ratio—to characterize lipid allocation (energy/structure) in the tissues of cyprid larvae and anticipated depleted TAG reserves in cyprids from less productive waters. Despite the considerably different levels of primary productivity between subtropical (1.31 ± 0.4 mg chl a m-3) and temperate waters (3.09 ± 1.2 mg chl a m-3), TAG/PL ratio and settlement success were comparable for C. bisinuatus and C. montagui. Lipid allocation of daily cohorts was also comparable for both chthamalids, with cyprids equally storing TAG reserves (≥50% of total lipid content). This points to an energetic threshold below which nauplii cannot develop to a cyprid and/or selection for lipid accumulation under poor trophic conditions. We highlight the challenges of directly relating estimates of primary productivity with food supply and larval physiological status, as lower chl a concentrations do not necessarily indicate food limitation for barnacle nauplii. We propose a conceptual model to clarify the process of lipid allocation (energetic to structural lipids) in the tissues of cyprid larvae.

AB - ABSTRACT: The transition of planktonic late-stage barnacle larvae to a benthic life requires enough energy to power settlement and metamorphosis, and may be compromised by food limitation during early ontogeny. We carried out a comparative study to better understand the larval physiology of space-monopolizing barnacles exposed to contrasting regimes of primary productivity: Chthamalus bisinuatus under a meso-oligotrophic regime on the southeastern coast of Brazil, and C. montagui under a highly productive regime on the southwestern coast of the British Isles. We used an index based on lipid composition—the triacylglycerol (TAG) to phospholipid (PL) ratio—to characterize lipid allocation (energy/structure) in the tissues of cyprid larvae and anticipated depleted TAG reserves in cyprids from less productive waters. Despite the considerably different levels of primary productivity between subtropical (1.31 ± 0.4 mg chl a m-3) and temperate waters (3.09 ± 1.2 mg chl a m-3), TAG/PL ratio and settlement success were comparable for C. bisinuatus and C. montagui. Lipid allocation of daily cohorts was also comparable for both chthamalids, with cyprids equally storing TAG reserves (≥50% of total lipid content). This points to an energetic threshold below which nauplii cannot develop to a cyprid and/or selection for lipid accumulation under poor trophic conditions. We highlight the challenges of directly relating estimates of primary productivity with food supply and larval physiological status, as lower chl a concentrations do not necessarily indicate food limitation for barnacle nauplii. We propose a conceptual model to clarify the process of lipid allocation (energetic to structural lipids) in the tissues of cyprid larvae.

U2 - https://doi.org/10.3354/meps13578

DO - https://doi.org/10.3354/meps13578

M3 - Article

VL - 661

SP - 147

EP - 161

JO - Marine Ecology Progress Series

JF - Marine Ecology Progress Series

SN - 0171-8630

ER -