Match or mismatch: the influence of phenology on size-dependent life history and divergence in population structure

• Published in: The Journal of animal ecology Vol. 79; no. 5; pp. 1101 - 1112
• Main Authors: Borcherding, Jost, Beeck, Peter, DeAngelis, Donald L., Scharf, Werner R.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01-09-2010; Blackwell Publishing; Blackwell Publishing Ltd; Blackwell
• Subjects: Abramis brama; Age Distribution; Animal and plant ecology; Animal ecology; Animal populations; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Body Size - physiology; Bream; Ecological competition; Ecological life histories; Ecology; Fish; Fresh water ecosystems; Fundamental and applied biological sciences. Psychology; General aspects; Hatching; hatching date; Life cycles; match-mismatch hypothesis; Models, Biological; Perca fluviatilis; Perciformes - physiology; Phenology; physiologically structured population model; Population Dynamics; Population ecology; Predation; predator-prey interactions; Predators; size variation; Stochastic Processes; Synecology; young-of-the-year; Zooplankton; Predator prey relation; Life history; Hatching; young-of-the-year; Population structure; predator-prey interactions; match-mismatch hypothesis; Freshwater environment; hatching date; Vertebrata; Phenology; Pisces; Perca fluviatilis; physiologically structured population model; Models; size variation; Teleostei; Osteichthyes
• ISSN: 0021-8790; 1365-2656
• DOI: 10.1111/j.1365-2656.2010.01704.x

1. In gape-limited predators, body size asymmetries determine the outcome of predator-prey interactions. Due to ontogenetic changes in body size, the intensity of intra- and interspecific interactions may change rapidly between the match situation of a predator-prey system and the mismatch situation in which competition, including competition with the prey, dominates. 2. Based on a physiologically structured population model using the European perch (Perca fluviatilis), analysis was performed on how prey density (bream, Abramis brama), initial size differences in the young-of-the-year (YOY) age cohort of the predator, and phenology (time-gap in hatching of predator and prey) influence the size structure of the predator cohort. 3. In relation to the seasonality of reproduction, the match situation of the predator-prey system occurred when perch hatched earlier than bream and when no gape-size limitations existed, leading to decreased size divergence in the predator age cohort. Decreased size divergence was also found when bream hatched much earlier than perch, preventing perch predation on bream occurring, which, in turn, increased the competitive interaction of the perch with bream for the common prey, zooplankton; i.e. the mismatch situation in which also the mean size of the age cohort of the predator decreased. 4. In between the total match and the mismatch, however, only the largest individuals of the perch age cohort were able to prey on the bream, while smaller conspecifics got trapped in competition with each other and with bream for zooplankton, leading to enlarged differences in growth that increased size divergence. 5. The modelling results were combined with 7 years of field data in a lake, where large differences in the length-frequency distribution of YOY perch were observed after their first summer. These field data corroborate that phenology and prey density per predator are important mechanisms in determining size differences within the YOY age cohort of the predator. 6. The results demonstrate that the switch between competitive interactions and a predator-prey relationship depended on phenology. This resulted in pronounced size differences in the YOY age cohort, which had far-reaching consequences for the entire predator population.