Interactive Effects of Lake Morphometry and Sticklebacks on the Trophic Position of Arctic charr, Salvelinus alpinus (L.), across Lakes in Western Greenland

Authors : Ignasi ARRANZ, Thomas Alexander DAVİDSON, Lluís BENEJAM, Sandra BRUCET, Javier SÁNCHEZ-HERNÁNDEZ, Frank LANDKİLDEHUS, Torben LAURİDSEN, Nestor MAZZEO, Nicolas VİDAL, Korhan ÖZKAN, Irene GALLEGO, Juliane WİSCHNEWSKİ, Rosemberg MENEZES, Tserenpil

Pages : 101-115

Doi:10.17216/limnofish.1020722

View : 13 | Download : 5

Publication Date : 2022-08-26

Article Type : Research Paper

Abstract :The structure and functioning of Arctic ecosystems have been drastically modified by global warming, with fish species potentially performing habitat shifts such as the northern expansion of generalist and warm-adapted species. The freshwater fish species Arctic charr insert ignore into journalissuearticles values(Salvelinus alpinus, hereafter charr); plays a key role in Arctic lake food webs, but sticklebacks insert ignore into journalissuearticles values(Gasterosteus aculeatus); may impact the trophic position insert ignore into journalissuearticles values(TP); of charr by affecting their habitat choice and food resources. In the present study, we used multiple regression analyses to examine the role of lake morphology insert ignore into journalissuearticles values(i.e., depth and area); and the influence of sticklebacks on the TP of charr insert ignore into journalissuearticles values(estimated from δ15N and δ13C); sampled in nine Arctic lakes in Western Greenland between 2011 and 2013. Results showed that charr populations exhibited larger TP values when co-occurring with sticklebacks. Specifically, for larger and deeper lakes, a significant positive effect on TP values was observed for medium-sized insert ignore into journalissuearticles values(25 to 35 cm); charr. Moreover, the TP of sticklebacks had a null effect on the TP values of the largest charr insert ignore into journalissuearticles values(> 40 cm);, suggesting that the largest-sized charr individuals did not prey on sticklebacks. We conclude that charr undergoes flexible ontogenetic trophic trajectories depending on the species composition of the Arctic fish community structure insert ignore into journalissuearticles values(here presence or absence of sticklebacks); and abiotic lake features.
Keywords : ecosystem size, food webs, polar regions, predator prey interactions, salmonids