Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2025
Erindi/veggspjald / Talk/poster E106
Höfundar / Authors: Daison Weedop, Camille Leblanc, Kári Heiðar Árnason, Grant Haines and Bjarni K. Kristjánsson
Starfsvettvangur / Affiliations: Háskóinnn á Hólum
Kynnir / Presenter: Bjarni K. Kristjánsson
The interactions between a prey and a predator is a common and long studied topic. Such interactions are dynamic and can vary temporarily because of changes in populations of prey, and/or predators, or the internal status of the predator. In ectotherms, predation and diet can vary with environmental factors such as photoperiod and temperature. In fishes, temperature directly affects metabolic rate and demand. Studying seasonal variation in diets of ectotherms is not trivial as both prey availability and predator status will vary, but can reveal important prey/predator interactions in food webs. Interactions between predator and prey are commonly only studied at one point in time. However, the diet of individuals, and populations, may change. For example, in relation to breeding and in n relation to temperature changes. Here we studied temporal variation in invertebrate communities and diet of cave dwelling Arctic charr, the main predator in this system. These fish are landlocked in small lava ponds and are highly dependent on external food input. We collected stomach content of Arctic charr and invertebrates from two lava caves in six occasions over one year. The results showed a considerable variation in diet between individuals, both between the two caves and over the year. The result show the importance of repeated samplings for a better understanding of prey/predators interactions of wild populations.