Going against the flow: effects of non-Gaussian dispersal kernels and reproduction over multiple generations

Our previous studies (Byers & Pringle 2006; Mar Ecol Prog Ser 313:27-41, Pringle & Wares 2007; Mar Ecol Prog Ser 335:69-84) discuss when populations and gradients in allele fre- quency can persist in the presence of a mean downstream dispersal of propagules from the parents' location. These studies assume that reproduction is uniform over the lifetime of the adult and that the larval dispersal kernel is 'nearly' Gaussian in shape. These results are extended in the present study to include variable reproduction over the lifetime of an adult and non-Gaussian dispersal kernels. It is found that persistence is governed by the lifetime reproductive output of the adults. The impact of non-Gaussian dispersal kernels is quantified in terms of the excess kurtosis of the dispersal kernel.