Personality does not predict individual niche variation in a freshwater fish

Animal populations can exhibit considerable inter-individual variation in both behavioral traits and niche use, but the potential connections between these characteristics are rarely compared for the same individuals. We aimed to test whether behavioral syndromes were predictive of individual diet or microhabitat in a native New Zealand freshwater fish, Gobiomorphus cotidianus. We carried out laboratory behavioral assays and repeated habitat and diet measurement in a semi-natural mesocosm system. We found considerable repeatability in individual behavior, largely consistent with a proactive/reactive behavioral syndrome. We also found modest individual repeatability in microhabitat use and relatively strong individual specialization in diet. However, no measure of niche use in the mesocosms was significantly predicted by individual personality. Further studies of this type will be needed to assess whether links between individual behavior and resource use are more important in other species or ecological contexts.
Methods
Data consist of behavioural assays of individual common bullies followed by measures of habitat use and diet in pond mesocosms. Most data are stored as averages or aggregated data at the individual level, but for some measures (behavioural assays, refuge use, prey mass) additional data files are provided for calculation of repeatability.