Grey plover (Pluvialis squatarola)
A team of young scientists and postdoctoral fellows at the Institute of Biodiversity and Ecosystem Studies, Bulgarian Academy of Sciences, has published results of the first study in Bulgaria using DNA metabarcoding for examination of the dietary spectrum of a species of shore birds at a resting stopover place during migration along the Bulgarian Black Sea coast. The grey plover (Pluvialis squatarola) breeds in the Arctic and winters on the coasts of Africa, reaching as far as the Republic of South Africa. It is observed on the Black Sea coast only during migration. The places where it stops for a few days to rest are very important for the survival of the birds because there they feed and thus replenish their energy reserves in order to continue their migration.
The study, led by doctoral student Lilyana Vasileva, investigated the composition of the diet of the grey plovers during its migration at the Pomorie Lake area. An innovative method was used – DNA metabarcoding. Fresh faeces of Pluvialis squatarola were collected from the shore of the sandbar separating Pomorie Lake from the sea and DNA was extracted from them. It was analysed to identify remains of which plant and animal species were present in faeces. The results of the analysis were compared with the available food resources in the habitats of the tidal zone and the sandy shore in the study area.
The study has shown that the grey plover has a wide food spectrum: a total of 332 species were identified by metabarcoding as its food. Both terrestrial and marine species were found. This shows that the birds feed in a variety of coastal habitats. The diet of the grey plover is dominated by terrestrial arthropods (especially insects), and the most represented marine component is mussels of the family Mytilidae. The grey plover displays a generalist feeding strategy (i.e. a wide food spectrum), consuming a variety of food in small quantities. This shows that both marine and coastal habitats are important for maintaining the food basis of this protected species.
The project was funded by the Bulgarian National Science Fund under the Young Scientists and Postdoctoral Fellows Programme (No. KP-06-M51/3 of 12.11.2021). The results are published in the December issue of the international journal Food Webs. The publication is available at the following link.
Food spectrum of the grey plovers in the Pomorie region revealed by DNA metabarcoding
