TY - JOUR

T1 - DNA metabarcoding suggests adaptive seasonal variation of individual trophic traits in a critically endangered fish

AU - Vilsen, Kurt

AU - Corse, E.

AU - Meglécz, E.

AU - Archambaud-Suard, G.

AU - Vignes, H.

AU - Ересковский, Александр Вадимович

AU - Chappaz, R.

AU - Dubut, Vincent

N1 - Publisher Copyright: © 2022 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.

PY - 2022/11

Y1 - 2022/11

N2 - Dietary studies are critical for understanding foraging strategies and have important applications in conservation and habitat management. We applied a robust metabarcoding protocol to characterize the diet of the critically endangered freshwater fish Zingel asper (the Rhone streber). We conducted modelling and simulation analyses to identify and characterize some of the drivers of individual trophic trait variation in this species. We found that population density and ontogeny had minor effects on the trophic niche of Z. asper. Instead, our results suggest that the majority of trophic niche variation was driven by seasonal variation in ecological opportunity. The total trophic niche width of Z. asper seasonally expanded to include a broader range of prey. Furthermore, null model simulations revealed that the increase of between-individual variation in autumn indicates that Z. asper become more opportunistic relative to summer and spring, rather than being associated with a seasonal specialization of individuals. Overall, our results suggest an adaptive variation of individual trophic traits in Z. asper: the species mainly consumes a few ephemeropteran taxa (Baetis fuscatus and Ecdyonurus) but seems to be capable of adapting its foraging strategy to maintain its body condition. This study illustrates how metabarcoding data obtained from faeces can be validated and combined with individual-based modelling and simulation approaches to explore inter- and intrapopulational individual trophic traits variation and to test hypotheses in the conventional analytic framework of trophic ecology.

AB - Dietary studies are critical for understanding foraging strategies and have important applications in conservation and habitat management. We applied a robust metabarcoding protocol to characterize the diet of the critically endangered freshwater fish Zingel asper (the Rhone streber). We conducted modelling and simulation analyses to identify and characterize some of the drivers of individual trophic trait variation in this species. We found that population density and ontogeny had minor effects on the trophic niche of Z. asper. Instead, our results suggest that the majority of trophic niche variation was driven by seasonal variation in ecological opportunity. The total trophic niche width of Z. asper seasonally expanded to include a broader range of prey. Furthermore, null model simulations revealed that the increase of between-individual variation in autumn indicates that Z. asper become more opportunistic relative to summer and spring, rather than being associated with a seasonal specialization of individuals. Overall, our results suggest an adaptive variation of individual trophic traits in Z. asper: the species mainly consumes a few ephemeropteran taxa (Baetis fuscatus and Ecdyonurus) but seems to be capable of adapting its foraging strategy to maintain its body condition. This study illustrates how metabarcoding data obtained from faeces can be validated and combined with individual-based modelling and simulation approaches to explore inter- and intrapopulational individual trophic traits variation and to test hypotheses in the conventional analytic framework of trophic ecology.

KW - conservation

KW - freshwater fish

KW - individual trait variation

KW - metabarcoding

KW - trophic niche

UR - http://www.scopus.com/inward/record.url?scp=85139396374&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/85a91a8b-6e85-3c2f-ac40-ef18b8d350b8/

U2 - 10.1111/mec.16698

DO - 10.1111/mec.16698

M3 - Article

VL - 31

SP - 5889

EP - 5908

JO - Molecular Ecology

JF - Molecular Ecology

SN - 0962-1083

IS - 22

ER -