Social learning in great white pelicans (Pelecanus onocrotalus): A preliminary study

Recombinase-aid amplification combined with lateral flow detection assay for sex identification of the great white pelican (Pelecanus onocrotalus)

Sex identification in avian species is essential for biodiversity conservation and ecological studies. However, the sex of nearly half of the birds could not be identified based on their external appearance. It is difficult to visually identify sex to monitor the ecology and conservation of wild populations. In this study, we designed primer pairs for large white pelican using recombinase-based isothermal amplification combined with a lateral flow dipstick (RAA-LFD) assay for chromo-helicase-DNA binding protein (CHD) genes mapped to W chromosomes and an ultra-conserved element (UCE) located on chromosome 6, respectively. Our result showed that the raaW4-RAA-LFD can detect up to 0.1 ng of genomic DNA (gDNA) templates of female pelicans in 30 min at 39 ℃ and accurately distinguish female from male without any cross reactivity. RaaUCE2-RAA-LFD can amplify both male and female pelicans with a detection limit of 25 pg. To further evaluate the assay, 15 white pelicans of unknown sex were tested using the RAA-LFD assay and conventional polymerase chain reaction (PCR). The results of the raaW4-RAA-LFD assay were consistent with those of the conventional PCR. The developed RAA-LFD assay is equipped with field-deployable instruments and offers a field platform for rapid and reliable sex identification in pelicans.

Understanding sociality and behavior change associated with a nesting event in a captive flock of great white pelicans

Zoo-housed pelicans are commonplace, but their breeding record is poor and little research is published on the activity patterns, as potential predictors of nesting, of captive flocks. Existing literature shows that comparative research can provide useful information for husbandry and conservation planning for pelican populations. The opportunity arose to investigate the time-activity budget and social network of a breeding flock of captive great white pelicans. Three chicks were hatched in June and July 2016 and one in March 2017. Data on state behaviors, space use, and association preferences were collected around these nesting events, from October 2016 to February 2017 and July to October 2017. Results suggest that pre-nesting periods were associated with heightened flock-wide vigilance, suggesting that vigilance may be a precursor for courtship or nesting activity. Social network analysis revealed nonrandom associations between birds and a social structure across the flock, in which subadults seemed to associate more with each other than with adult birds. A limited visitor effect was noted; whilst no overall behavior change was apparent with different numbers of visitors, pelicans did widen their enclosure usage with increased visitor presence. These data are relevant to those attempting to breed this pelican, who wish to know more about the daily behavior patterns of this species across the season and physiological state, and who wish to understand pelican social structure, which is useful to the planning and implementation of bird moves or changes to the social environment of the flock. Further extending such research to include uninterrupted observation over a successful breeding event is recommended.