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Oecologia (2009) 160:7786 DOI 10.1007/s00442-009-1287-z
PLANT-ANIMAL INTERACTIONS - ORIGINAL PAPER
Spatial variability in seed predation in Primula farinosa: local population legacy versus patch selection
Didrik Vanhoenacker Jongren Johan Ehrln
Received: 28 July 2008 / Accepted: 8 January 2009 / Published online: 12 February 2009 Springer-Verlag 2009
Abstract Spatio-temporal variation in seed predation may strongly inuence both plant population dynamics and selection on plant traits. The intensity of seed predation may depend on a number of factors, but the relative importance of previous predator abundance (local legacy), spatial distribution of the host plant, environmental factors and plant characteristics has been explored in few species. We monitored seed predation in the perennial herb Primula farinosa, which is dimorphic for scape length, during 5 consecutive years, in a 10-km 9 4-km area comprising 79 P. farinosa populations. A transplant experiment showed that the seed predator, the oligophagous tortricid moth Falseuncaria ruciliana, was not dispersal limited at the spatial scale corresponding to typical distances between P. farinosa populations. Correlations between population characteristics and incidence and intensity of seed predation varied among years. The incidence of the seed predator was positively correlated with host population size and mean number of owers, while intensity of seed predation in occupied patches was positively related to the frequency of the long-scaped morph in 2 years and negatively related to host population size in 1 year. In both scape morphs, predation tended to
increase with increasing frequency of the long morph. There was no evidence of a local legacy; incidence and intensity of seed predation were not related to the abundance of the seed predator in the population in the previous year. Taken together, the results indicate that among-population variation in seed predation intensity is determined largely by patch selection and that the seed predators preference for tall and many-owered inorescences may not only affect selection on plant traits within host plant populations, but also the overall intensity of seed predation.
Keywords Floral display Metapopulation
Polymorphism Population density Tortricidae
Introduction
Biotic interactions ubiquitously vary over time and space (Andrewartha and Birch 1954; Roslin and Kotze 2005). This may result in spatial variation in population dynamics of interacting species as well as complex and dynamic selection mosaics (e.g. Thompson 2005; Rey et al. 2006). Assessing...