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Freshwater threespine stickleback fall along a benthic (bottom feeding)–limnetic (plankton feeding) continuum of ecotypes. Although trophic and courtship behaviour are well-described, the full reproductive cycle has not been characterized in the ecotypes. We provide detailed in situ descriptions of the reproductive cycle of males in one population of each ecotype, and a less detailed description in one oceanic population likely to represent the ancestral form that gave rise to the post-glacial freshwater radiation in southern British Columbia. All populations exhibited typical patterns including: pre-spawning nest building, fanning (which peaked in intensity just before hatching of embryos), and gluing (which was most common from nest building through the early parental phase). These elements of behaviour may be fixed by the physiological requirements of the fry. Males in the benthic and oceanic populations interacted frequently with groups and solitary non-neighbours, reflecting the abundance of bottom-feeding adults. Interactions with groups did not occur in limnetic populations and those with solitary non-neighbours were rare. Interactions were common with neighbours in all populations, but in the limnetic population they were conspicuous and ritualized, rather than the simple chases observed in the other populations. Males in the limnetic population also attended to the nest more, in some cases producing a 3-cm mound of sediment following the completion of spawning and often placing rushes around the pit-nest. The general pattern was one in which males in the cannibalistic benthic and oceanic populations appeared to be constrained in their interactions with neighbours and their attention to the nest by the need for vigilance and nest defense, while limnetic males attended more to nests and neighbours, possibly exhibiting the optimal pattern of nest-directed activities for the fry. [ABSTRACT FROM AUTHOR]

The threespine stickleback superspecies has become a model for evolutionary studies of morphology, behaviour, early-life development and host–parasite relationships. Its potential value for studying life-history evolution is also great. Fourteen years ago, a review of female stickleback life-history illustrated both the potential of the system to inform life-history evolution, and the limitations of the data at the time. In the succeeding years much more information has become available, especially from northwestern North America. Additionally, much more information is now available for the ancestral marine stickleback, a deficiency that was highlighted in the first stickleback book. One purpose of this review was to update information on female life history in the species. To this end, variation in the major life-history correlates (reproductive effort, clutch size, egg size and age/size at reproduction) is described, and a description of geographical structuring of this variation is provided. A second goal was to go beyond variation in individual traits to explore variation in trait correlations. The review ends with an exploration of allometric relationships between life-history traits and female size. [ABSTRACT FROM AUTHOR]