Bay pipefish, Syngnathus leporhychus, are a polygamous species characterized by a high degree of male uniparental care. Like other members of the Syngnathidae family, male bay pipefish are assured to be the father of the embryos they care for, as fertilization takes place within their pouch (Ahnesjo 1992, Foster and Vincent 2004, Wilson 2006). S. leptorhynchus become sexually mature at 60-80 days (Fritzsche 1980, Wilson 2009), with reproductive activity overall higher during summer months (Fritzsche 1980, Wilson 2006). However, this activity varies in populations depending on their geographical location; southern populations have been found to reproduce often throughout the year, while some northern populations reproduce in a period of two months. It is possible that within one year, male bay pipefish found in California are able to raise as many as 12 broods (Fritzsche 1980, Wilson 2009). Female S. leptorhynchus in northern populations may participate in “bet-hedging”, where they mate with and distribute their eggs across multiple males since in a harsh environment the chances are lower that the offspring from each male will survive (Wilson 2009).

References:

Ahnsejo, I. 1995. Temperature affects male and female potential reproductive rates differently in the sex-role reversed pipefish, Syngnathus typhle. Behavioral Ecology, 6: 229-233.

Foster, S.J., Vincent, A.C.J. 2004. Life history and ecology of seahorses: implications for conservation and management. Journal of Fish Biology, 65: 1-61.

Fritzsche, R.A. 1980. Revision of the eastern Pacific Syngnathidae (Pisces: Syngnathiformes), including both recent and fossil forms. Processings of the California Academy of Sciences, USA, 42: 181-227.

Wilson, A. B. 2006. Interspecies mating in sympatric species of Syngnathus pipefish. Molecular Ecology, 15: 809–824.

Wilson, A. B. 2009. Fecundity selection predicts Bergmann's rule in syngnathid fishes. Molecular Ecology, 18: 1263–1272.