Mate quality and the temporal dynamics of breeding in a sex-role-reversed pipefish, S. typhle
The spatiotemporal dynamics of receptivity and breeding date, coupled with individual-level quality and attractiveness, are centrally important to mating system dynamics. These topics have been investigated in some detail in birds, but much less work has been devoted to other taxonomic groups, and almost no work has addressed spatiotemporal factors and individual quality in sex-role-reversed taxa. The broad-nosed pipefish, Syngnathus typhle, provides an excellent opportunity to investigate these ideas in a sex-role-reversed fish. Here, we addressed three questions related to mating dynamics in S. typhle: (1) Do higher-quality males arrive earlier on the breeding grounds and mate first? (2) Are early-breeding males in better condition than later-breeding males? And (3) do mating events involving higher-quality males produce better clutches than mating events involving lower-quality males? We collected data from a field study and a laboratory breeding experiment to address our hypotheses. Our results show that larger males mate earlier than smaller males and that pregnant males have higher measures of condition compared to non-pregnant males. Moreover, our laboratory results demonstrate that pairings between larger males and preferred females yielded more offspring than pairings involving smaller males. In summary, the spatiotemporal dynamics of S. typhle breeding patterns, combined with variation in individual quality, play an important role in shaping mating systems and should be incorporated in future analyses of mating behavior and sexual selection in this interesting sex-role-reversed pipefish.
The breeding patterns of a species can fluctuate over time due to a number of factors, one of which is individual quality. Although the effects of both the timing of reproduction and female quality on mating systems have been studied in some species, they have been investigated primarily in isolation. Here, we demonstrate that individual quality and the timing of reproduction interact to affect reproductive success in a wild population of sex-role-reversed fish.
KeywordsSyngnathus typhle Reproductive success Condition Breeding date Mating systems
Thanks to A. Berglund for contributing to project design and to S. van Leeuwen, C. Seger, and R. Höglund for the assistance with fish care and laboratory work. A. Berglund, K. Wedemeyer-Strombel, E. Rose, and A. Anderson and four anonymous reviewers commented on previous drafts of this manuscript. We thank Uppsala University-Campus Gotland for being able to use Ar research station.
Compliance with ethical standards
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. All handling of fish was done under license Dnr 118-2008 from the Swedish Board of Agriculture. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223257. SPF was supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1252521, supplemented by a GROW supplement in connection with the Norwegian Research Council. This work was conducted in part while SPF was a Postdoctoral Fellow at the National Institute for Mathematical and Biological Synthesis, an Institute sponsored by the National Science Foundation through NSF Award #DBI-1300426, with additional support from the University of Tennessee, Knoxville. This work was funded by grant number DEB-1119261 from the National Science Foundation to AGJ and by grant number DEB-1401688 to AGJ and SPF. The authors declare that they have no conflict of interest.