Dear MARMAM community,
On behalf of my co-authors and me, I am very pleased to share our latest publication in Endangered Species Research:
Zeppetelli-Bedard L, Sherrill M, Ewald J, Pang Z, Cabrol J, Lesage V, Michaud R, Verreault J (2026) Comparative non-targeted lipidomic profiles in blubber of endangered St. Lawrence Estuary belugas and their potential prey. Endang Species Res 60:esr01501 https://doi.org/10.3354/esr01501
ABSTRACT: The
St. Lawrence Estuary (SLE) belugas Delphinapterus leucas are a small and
isolated population listed as endangered in Canada. Profound changes in the SLE
ecosystem and a parallel deterioration in SLE beluga body condition suggest a
potential decline in the quality and/or quantity of their prey. Using a
non-targeted screening approach, this study aimed to gain insights into the
blubber lipid profiles of SLE belugas and their potential prey, and to examine
variations among beluga males and females and age classes, as well as among
prey taxa and sampling seasons. Ultra-high performance liquid chromatography
tandem mass spectrometry (UHPLC-MS/MS) was used to analyze 71 SLE beluga
blubber biopsies (outer blubber layer) and 126 prey homogenates from 10 fish and 2
invertebrate species. Over 10383
features were detected across
SLE beluga and prey samples,
highlighting structural lipids such as glycerolipids, sphingolipids, and glycerophospholipids
as the predominant components. Distinct lipid profiles were found between SLE
beluga males and females, suggesting potential differences in diet and lipid
metabolism, thus underscoring the importance of considering sex-specific lipid
variations in beluga blubber. Prey species displayed unique lipid fingerprints,
clustering according to phylogeny, diet, and trophic guilds. Significant
seasonal variations in lipid composition were also observed in prey sampled
across seasons. This study constitutes a critical first step toward assessing
beluga–prey ecological interactions and lipid composition in the SLE food web,
as well as how lipid composition influences energy allocation and storage.
Cheers,
MSc., University of Quebec in Montreal, Canada
Aquatic science technician at Fisheries and Oceans Canada
Laura.zeppbed@gmail.com or laura.zeppetelli-bedard@dfo-mpo.gc.ca
Tel.: (514)-691-9712