Regurgitated skua pellets containing the remains of South Atlantic seabirds can be used as biomonitors of small buoyant plastics at sea

Vonica Perold; Maëlle Connan; Giuseppe Suaria; Eleanor A Weideman; Ben J Dilley; Peter G Ryan

doi:10.1016/j.marpolbul.2024.116400

Regurgitated skua pellets containing the remains of South Atlantic seabirds can be used as biomonitors of small buoyant plastics at sea

Mar Pollut Bull. 2024 Apr 30:203:116400. doi: 10.1016/j.marpolbul.2024.116400. Online ahead of print.

Authors

Vonica Perold¹, Maëlle Connan², Giuseppe Suaria³, Eleanor A Weideman⁴, Ben J Dilley⁴, Peter G Ryan⁴

Affiliations

¹ FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa. Electronic address: vperold@gmail.com.
² Department of Zoology, Marine Apex Predator Research Unit (MAPRU), Institute for Coastal and Marine Research, Nelson Mandela University, Gqeberha, South Africa.
³ CNR-ISMAR (Institute of Marine Sciences - National Research Council), Lerici 19032, La Spezia, Italy.
⁴ FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa.

PMID: 38692002
DOI: 10.1016/j.marpolbul.2024.116400

Abstract

Using seabirds as bioindicators of marine plastic pollution requires an understanding of how the plastic retained in each species compares with that found in their environment. We show that brown skua Catharacta antarctica regurgitated pellets can be used to characterise plastics in four seabird taxa breeding in the central South Atlantic, even though skua pellets might underrepresent the smallest plastic items in their prey. Fregetta storm petrels ingested more thread-like plastics and white-faced storm petrels Pelagodroma marina more industrial pellets than broad-billed prions Pachyptila vittata and great shearwaters Ardenna gravis. Ingested plastic composition (type, colour and polymer) was similar to floating plastics in the region sampled with a 200 μm net, but storm petrels were better indicators of the size of plastics than prions and shearwaters. Given this information, plastics in skua pellets containing the remains of seabirds can be used to track long-term changes in floating marine plastics.

Keywords: Biomonitor; Plastic ingestion; Polymers; Seabirds; South Atlantic Ocean; Storm petrels.