Latitudinal Variation in Common Carp Populations Indicate Potential Responses to Climate Change

Temperature is a major factor regulating fish life history traits. Global climate change is expected to alter the temperature regimes experienced by fish and could potentially alter available habitat or life history traits of many species.  Variation in life history traits of fish from different latitudes could provide information about how temperature changes associated with climate change may affect freshwater fishes.   However, latitudinal life history variation in fishes is poorly understood.  To understand how climate change may alter life history characteristics of invasive freshwater fishes, we collected common carp Cyprinus carpio, from 21 populations across North America. We measured relative abundance and aged fish using dorsal spines from each population to calculate recruitment variability, von Bertalanffy growth coefficient (K) and asymptotic body length (L_∞), total length at age three, proportional size distributions, maximum observed total length, annual mortality, and mean and maximum observed ages.  We then related these life history characteristics to latitude using correlation analysis.  Common carp growth rates (K), size at age three, and mortality decreased with increased latitude whereas L_∞, maximum observed size, size structure, and mean and maximum observed age increased with increased latitude.  Our findings suggest that invasive common carp may experience increased growth but attain smaller sizes due to higher mortality in response to increased average annual temperature resulting from climate change at temperate latitudes.