Female nuptial signals (FNSs) advertise reproductive state, individual quality, and are used in intrasexual competition. I explored whether pelagic-spawning pink-belly wrasse (Halichoeres margaritaceus) used red belly colouration and a unique bobbing behaviour as FNSs to advertise spawning readiness. I examined (i) if there was a temporal pattern in belly colour and incidence of bobbing, as each related to spawning; (ii) response of female belly colouration during male courtship behaviours; and (iii) pink belly area as it related to body area and bobbing rate. Temporal patterns were detected, females displayed ephemeral red belly colour and bobbing behaviour prior to spawning; females displaying red belly colouration elicited more courtship behaviour from males than females with white or pink belly colouration, and larger females displayed larger red belly areas. Benefits to advertising spawning readiness in pink-belly wrasse are discussed, including a reduction in mate-searching costs and potential for increased reproductive success through sex-change.

Few studies estimate the impact of individual size on annual reproductive output, which is an important consideration where size‐selective harvest may truncate size distributions and sharply reduce populationwide reproductive potential. We conducted a 2‐year study of reproduction in field‐collected and captive tautog Tautoga onitis from Long Island Sound to investigate the influence of individual size on components that constitute annual fecundity: Batch fecundity, spawning frequency, and season duration. Estimates of spawning frequency in field‐caught females relied on time‐varying features of postovulatory follicles that we validated in experiments conducted on captive spawners. Mature females collected in the wild demonstrated midseason peaks in spawning frequency and batch size. Both spawning frequency and batch fecundity increased significantly with size. As a result, annual fecundity increased sharply with size: Large (500‐mm) females produced 24‐86 times as many eggs as did small (250‐mm) females. Average (400‐mm) females spawned 10‐16 million eggs over a season, or about 10,000 eggs/g of whole body mass. We estimated temporal changes in populationwide egg production with data from a 22‐year trawl survey in Long Island Sound. Over this period, an index of abundance declined by a factor of six and size distributions shifted to smaller fish. Despite the shift in size distribution, estimated annual egg production declined no more than the index of abundance because the sex ratio of the population has become female biased. Estimates of tautog annual fecundity were higher than those reported previously in the southern portion of the species' range, reflecting genetic differentiation or phenotypic responses to environmental effects. Given the relatively large reproductive output of large females, their abundance is likely to influence the rate of population recovery in Long Island Sound.

Male ram cichlid, Mikrogeophagus ramirezi, spent significantly more time associating with animated female images compared to static images of the same female, indicating that males of the species reliably respond to computer‐animated images of conspecific females. Female M. ramirezi temporarily display a pink‐coloured belly, and this study showed that males spent significantly more time associating with animated female images displaying a pink‐coloured belly compared to animated female images with pink belly colour removed. This is the first study to report male mate choice in M. ramirezi, a neotropical monogamous dwarf cichlid.

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