Journal article
Cormorant predation on PIT-tagged lake fish
National Institute of Aquatic Resources, Technical University of Denmark1
Section for Freshwater Fisheries Ecology, National Institute of Aquatic Resources, Technical University of Denmark2
Section for Marine Living Resources, National Institute of Aquatic Resources, Technical University of Denmark3
Institute Management, National Institute of Aquatic Resources, Technical University of Denmark4
The present study use data from recovered PIT (Passive Integrated Transponder) tags to explore species-and size-specific annual predation rates by cormorants on three common lacustrine fishes (size range 120-367 mm) in a European lake; roach (Rutilus rutilus), common bream (Abramis brama) and perch (Perca fluviatilis).
In addition, we quantify the level of age/size truncation that cormorant predation could introduce in a population of perch, an important fish for recreational angling as well as for trophic interactions and ecosystem function in European lakes. Based on three years of PIT tagging of fish in Lake Viborg and subsequent recoveries of PIT tags from nearby cormorant roosting and breeding sites, we show that cormorants are major predators of roach, bream and perch within the size groups we investigated and for all species larger individuals had higher predation rates.
Perch appear to be the most vulnerable of the three species and based on a comparison with mortality estimates from lakes without significant avian predation, this study suggest that predation from cormorants can induce age/size truncation in Lake Viborg, leaving very few larger perch in the lake. This truncation reduces the likelihood of anglers catching a large perch and may also influence lower trophic levels in the lake and thus turbidity as large piscivorous perch often play an important structuring role in lake ecosystem functioning.
Language: | English |
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Publisher: | PAGEPress Publications |
Year: | 2014 |
Pages: | 177-186 |
ISSN: | 17238633 and 11295767 |
Types: | Journal article |
DOI: | 10.4081/jlimnol.2014.715 |
ORCIDs: | Skov, Christian , Jepsen, Niels , Baktoft, Henrik , Jansen, Teunis , Pedersen, Stig and Koed, Anders |
07508, Ecology: environmental biology - Animal 07514, Ecology: environmental biology - Limnology Abramis brama Aves Vertebrata Chordata Animalia (Animals, Birds, Chordates, Nonhuman Vertebrates, Vertebrates) - Pelecaniformes [85550] cormorant common DIET ESTUARY Ecology, Environmental Sciences Freshwater Ecology GREAT CORMORANTS LIMNOLOGY Lake Viborg Denmark, Europe Palearctic region PERCH PERCA-FLUVIATILIS PHALACROCORAX-CARBO-SINENSIS PIT tags POPULATION-DYNAMICS Passive Integrated Transponder Perca fluviatilis Pisces Vertebrata Chordata Animalia (Animals, Chordates, Fish, Nonhuman Vertebrates, Vertebrates) - Osteichthyes [85206] Perca fluviatilis species perch common Rutilus rutilus species roach common Abramis brama species common bream common RIVER Rutilus rutilus SDG 15 - Life on Land SIZE STOCKS YELLOW PERCH avian predation mortality recreational angling species annual predation rate species ecosystem function species mortality species trophic interaction