Behavioural and genetic aspects of mating systems have
been extensively studied in syngnathid fishes. All species
have elaborate courtship behaviours involving display
with only one partner (social monogamy) or multiple
partners (social polygamy). Multiple mating is common
in pipefish (Jones & Avise 1997; Wilson 2006b; reviewed in
Jones & Avise 2001) but field studies indicate that seahorses
are strictly monogamous during each brooding period
(reviewed in Foster & Vincent 2004). A range of behavioural
factors may promote monogamy in seahorses, including
parental care combined with mate sequestration and
territorial defence (see review in Whiteman & Cote 2004).
It has also been suggested that reproductive synchronization
in seahorses may restrict opportunities for multiple
mating (Vincent
et al
. 2004).