Atıf İçin Kopyala
Arranz I., Davidson T. A., Benejam L., Brucet S., Sánchez-Hernández J., Landkildehus F., ...Daha Fazla
JOURNAL OF LIMNOLOGY AND FRESHWATER FISHERIES RESEARCH, cilt.8, sa.2, ss.101-115, 2022 (Hakemli Dergi)
Özet
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 (Salvelinus alpinus, hereafter charr) plays a key role in Arctic lake food webs, but sticklebacks (Gasterosteus aculeatus) may impact the trophic position (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 (i.e., depth and area) and influence of sticklebacks on the TP of charr (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 (25 to 35 cm) charr. Moreover, the TP of sticklebacks had a null effect on the TP values of the largest charr (> 40 cm), suggesting that the largest-sized charr individuals did not prey on sticklebacks. We conclude that charr undergo flexible ontogenetic trophic trajectories depending on the species composition of the Arctic fish community structure (here presence or absence of sticklebacks) and abiotic lake features.