Investigating parental care behaviour in same-sex pairing of zoo greater flamingo (Phoenicopterus roseus)

Abstract

Same-sex pair bonds have been documented in several animal species and they are widespread in birds. However, little is known about the evolutionary origin and the adaptive value of such behaviour. The aim of this study was to investigate the parental behaviour of four zoo female greater flamingos involved in two breeding pairs, housed in a flock at Parco Natura Viva, Italy. Further, the behaviour of the study females was compared with that of male and female flamingos in heterosexual pairs described in a previous published work on this same flock. For each pair, the behaviour of both birds during the incubation period was recorded and twenty 10-minute sessions were run within the incubation period. A continuous focal animal sampling method was used to collect data on location (on the nest or not on the nest) and the parental care behaviour (e.g.: agonistic behaviours toward disturbing conspecifics, egg-care, nest-building, self-comfort behaviour, sleeping) of the two pairs. Data of the current study females were compared with those of females and males involved in heterosexual pairs of this same flock. Results showed that within each pair the egg-layer female stayed away from the nest more than the other female. In addition, the female that did not lay an egg was more involved in agonistic behaviour compared to other females, particularly when in specific locations. In heterosexual pairs, male flamingos were more involved in the incubation and in nest protection. Moreover, no significant differences in the time spent on the nest and away from the nest between the heterosexual male and the non-layer females of same-sex pairs were found. The same findings were reported when comparing heterosexual females and the egg-layer females of the same-sex pairs. Therefore, our findings suggest that in greater flamingos the behaviour of the female–female pairs seems to be equivalent to that of male-female bonds. Such research provides more insight into flamingo social behaviour, and their reproductive cycle, and provides information on why pair bonds may form and how these affect the wider breeding behaviour of the flock.

Group Reunion in Zoo European Wildcats Using Cat Appeasing Pheromone (CAP) and Gradual Release of the Animals in the Exhibit—A Case Study

“…A single-case design was performed to analyse behavioural data of wildcats, using the total duration of each session calculated for each subject as dataset [46,47]. Nonparametric statistical tests were used to compare behavioural data of wildcats between and within periods.…”

Ancestral sex-role plasticity facilitates the evolution of same-sex sexual behavior

“…Our results suggest that ancestral behavioral plasticity played an essential role in the evolution of SSB in termites. The importance of sex-role plasticity in SSB is likely to be widely relevant because expression of behaviors associated with the other sex is frequently observed in other taxa (9,10). Therefore, our results have implications for understanding the nearly ubiquitous evolutionary maintenance of SSB across sexually reproducing animal taxa (1-4).…”

“…SSB is often more than misdirected behavior otherwise expressed during heterosexual encounters. In many species, sexual interactions between same-sex partners involve at least one partner expressing behaviors associated with the other sex, such as mimicking the other sex (9) or expressing the other sex's role during pair bonding (10), and evidence is emerging that SSB can involve distinct behavioral repertoires with separate neurological causation (11). The sex of the partner in a same-sex pairing is different from that in a heterosexual pairing, so plastic responses to different sociosexual environments should be essential for the expression of SSB.…”

Ancestral sex-role plasticity facilitates the evolution of same-sex sexual behaviour

“…e . interacting partners being courted, mounted, paired, or receiving a copulation attempt) is often lacking, and as a result, it is underappreciated that both individuals may modify their behaviour during SSB to maintain same-sex pairing [40]. In this study, we empirically demonstrated that one of the partners in a same-sex pairing of termites flexibly expresses the behaviour of the other sex to contribute to pair coordination.…”