Drivers of growth in a keystone fished species along the European Atlantic coast: The common cockle Cerastoderma edule
Langue
EN
Article de revue
Ce document a été publié dans
Journal of Sea Research (JSR). 2022-01-01, vol. 179, p. 102148
Résumé en anglais
A better understanding of growth drivers in shellfish populations including the common cockle Cerastoderma edule is essential, as their future is challenged by unsustainable fishing practices and climate change. In this ...Lire la suite >
A better understanding of growth drivers in shellfish populations including the common cockle Cerastoderma edule is essential, as their future is challenged by unsustainable fishing practices and climate change. In this study
the spatial and temporal variabilities in common cockle growth across latitudes were assessed and compared
with historical data. Six locations were examined at bimonthly intervals over 19 months; three Irish, two Welsh
and one French, spanning the latitudes 54◦N to 44◦N. The results demonstrated that local abiotic and biotic
factors have a larger impact on cockle growth than latitude. Cockles at similar latitudes grew at different rates
and sizes, possibly due to factors such as density, fishing activity and interspecific competition. Cockles (0–3
years) impacted by low salinity and parasites (trematodes), exhibited reduced growth in later years. At the
warmest, southernmost site growth was lowest in cockles >2 years. Previously, cockles at that site have been
shown to spawn almost year-round, possibly diverting energy to gonad development rather than growth. The
results opposed previously literature which demonstrated significantly greater growth at lower latitudes. These
findings affirm that cockle growth and size is variable due to local abiotic (reduced salinity) and biotic
(potentially trematode infection) drivers. Additionally, the synergistic relationship between these factors, i.e.
warmer temperatures driving prolonged spawning, and the potential association between lower salinities and
trematode prevalence, is concerning due to predicted climate related increases in temperature, precipitation and
trematode prevalence/transmission, which may result in northern cockles reaching smaller maximum sizes.< Réduire
Mots clés en anglais
von Bertalanffy growth model
Cockles
Stable isotopes
Shellfish
Climate change
Fisheries