What’s on the menu for the resident brown trout in a rich limestone stream?
2021
Authors:
Čanak Atlagić, JelenaMarić, Ana
Tubić, Bojana
Anđus, Stefan
Đuknić, Jelena
Marković, Vanja
Paunović, Momir
Simonović, Predrag
Document Type:
Article (Published version)
Metadata
Show full item recordAbstract:
Examination of brown trout seasonal diet variation and investigation of terrestrial prey importance in a food-rich stream using four indices of prey importance (number and weight abundance, frequency of occurrence, index of relative importance) revealed that aquatic prey constituted the major part of the diet (>90%) throughout the examined period. Despite Gammaridae being the most abundant in the environment, other less abundant organisms appeared to be important prey, including terrestrial organisms, with maximum consumption in September. The electivity index showed a positive selection of rare prey types; Tokeshi’s model revealed a specialist strategy for most of the population, except for those of 1+ age, who were inclining to generalist strategy. Diet diversity increased throughout April to October, and ages 1+ and 2+ exhibited a more diverse diet than older ages. Diet overlap between age classes was considerable, with less overlap observed in the later season. This pattern of differentiation in the diet of brown trout age classes and their feeding plasticity over seasonal scales, as observed in this food-rich stream, provides a starting point for further examination of this topic in streams with similar or different food richness and availability.
Keywords:
Brown trout diet; Diet diversity; Feeding ecology; Ontogenetic shift; SelectivitySource:
Water (Switzerland), 2021, 13, 18, 2492-Funding / projects:
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200007 (University of Belgrade, Institute for Biological Research 'Siniša Stanković') (RS-MESTD-inst-2020-200007)
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200178 (University of Belgrade, Faculty of Biology) (RS-MESTD-inst-2020-200178)
DOI: 10.3390/w13182492
ISSN: 2073-4441