The Roles of Climate and Community Size Structure in Shaping the Life Histories of Limnetic Top Predators: An Empirical Assessment Using Several Continental Data Sets

The relative importance of environmental temperature and prey availability in shaping somatic growth rate and reproductive allocation in freshwater fish has been the subject of much recent theoretical and empirical work.  In this paper, we use extensions of the biphasic growth model of Lester et al (2004) to make a quantitative assessment of: (i) the nature of the constraints that the seasonal water temperature cycle places on juvenile somatic growth rate; (b) the nature of the constraints that the prey size spectrum places on reproductive allocation and the consequences for adult somatic growth.  We use six data sets that document continent-wide variation in the life-time somatic growth patterns of 2 cold water species (lake trout in North America, brown trout in Europe), 3 cool water species (walleye and yellow perch in North America, European perch in Europe) and 1 warmwater species (smallmouth bass in North America).  Comparative analyses of these data reveal many similarities and some differences in the degree to which variation in observed growth patterns can be linked to environmental differences in seasonal temperature patterns and ecological differences in prey size distributions.