The function of daily greetings in a monogamous pipefish Corythoichthys haematopterus

Abstract

Ritualized morning interactions, called greeting, were investigated for a natural population of the monogamous pipefish Corythoichthys haematopterus. Every morning, pair members moved to a fixed site in their overlapped home ranges within an hour of sunrise to engage in greetings for a few minutes. After the greetings, they separated and each returned to its original site. On the day of spawning, the behavioural pattern of greetings differed from that on the other days and exchanged displays intermittently until spawning, which occurred 1-3 h after sunrise. In the field experiment where either of pair members was isolated in a cage for a day, the temporarily mate-losing fish (called resident fish) approached an unpaired fish of the opposite sex, which was released at the greeting site next morning, but thereafter few interactions occurred between them. In contrast, when the partner was released after the withdrawal of the unpaired fish, the resident fish immediately approached it and they exchanged greetings. This fact suggests that each individual discriminates its partner from others. The function of daily greetings in this pipefish is discussed from aspects of the reproductive synchronization of a pair and the maintenance of monogamy without mate guarding.

Partner recognition in a perennially monogamous pipefish, Corythoichthys haematopterus

“…Because I used fish of paired status (i.e., in reproduction) and sizematched pairs in the interpair treatment, it is unlikely that the experimental fish failed to show interest in each other simply because their counterpart was not attractive as a potential mate. A previous study reported that the greeting site is consistent with the location where the most recent spawning occurred (Sogabe and Yanagisawa 2007a). Pair members would be able to encounter each other efficiently Our results, however, indicate that the location is not a necessary requirement for partner recognition.…”

Male Ornamentation in a Sex‐Role Reversed Pipefish Corythoichthys haematopterus

“…The ability to discriminate the partner from others may provide fitness benefit to individuals forming a long‐term pair bond, because they can shorten the time for courtship before spawning, cooperate harmoniously in parental care or prevent hostilities to the partner (Tibbetts & Dale 2007). Although pair members do not stay together except during the time of greetings, which last only a few minutes in early morning, the pair of C. haematopterus is maintained throughout the year, suggesting their remarkable ability of partner recognition (Sogabe & Yanagisawa 2007b, 2008). The female of a pair may therefore use the male ornament as a cue for partner recognition.…”

“…obs.). This ornament is visible from a distance when males are raising their head to exhibit courtship or greeting behaviour (Matsumoto & Yanagisawa 2001; Sogabe & Yanagisawa 2007b, 2008).…”

“…obs.). This ornament is visible from a distance when males are raising their head to exhibit courtship or greeting behaviour (Matsumoto & Yanagisawa 2001;Sogabe & Yanagisawa 2007b. To understand the function of this ornamental trait, we examined in a laboratory controlled experiment (1) whether the presence of females affects the expression of this trait in males and (2) whether the expression of this trait depends on the male's physical condition.…”

Mate Change Reduces the Reproductive Rate of Males in a Monogamous Pipefish Corythoichthys haematopterus: The Benefit of Long‐Term Pair Bonding

“…Therefore, there appears to be a high opportunity for C. haematopterus males to sequentially mate with more than one female. However, neither mate guarding by females nor female–female aggression occurs in C. haematopterus except for the time of greeting and spawning (Matsumoto & Yanagisawa 2001, Sogabe & Yanagisawa in press), unlike other monogamous fishes (Takegaki 2000; Kokita 2002). It is known in syngnathids that the number and size of eggs are positively correlated with female body size (Berglund et al.…”