Using beached bird data to assess seabird oiling susceptibility

Oil spills can cause severe impacts on seabirds, the extent of which varies by species. We investigated taxon-specific susceptibility using data from the Nestucca and Tenyo Maru oil spills in the northeast Pacific together with seasonally and spatially overlapping baseline beached bird abundance data collected over a 17-year time-period. Multivariate analyses revealed patterns of variation between spill and non-spill data, primarily driven by differences in the relative abundance of common murres (Uria aalge) and northern fulmars (Fulmarus glacialis). In subsequent susceptibility analyses, alcid (Alcidae spp.) carcasses were generally overrepresented in spill data, while gulls (Larus spp.), tubenoses (Procellariformes spp.), and cormorants (Phalacrocoracidae spp.) were generally under-represented. We found that the baseline data had high variability, suggesting a need for many years of baseline data. We propose that where appropriate baseline data exists, this method can be employed to investigate the seabirds most vulnerable to oiling.

The use of beached bird surveys for marine plastic litter monitoring in Ireland

Marine plastic litter has become a major threat to wildlife. Marine animals are highly susceptible to entanglement and ingestion of debris at sea. Governments all around the world are being urged to monitor litter sources and inputs, and to mitigate the impacts of marine litter, which is primarily composed of plastics. European policies, such as Oslo-Paris Convention (OSPAR) and Marine Strategy Framework Directive (MSFD) have adopted the monitoring of a seabird species, the Northern Fulmar (Fulmarus glacialis), as an environmental quality indicator through the analysis of stomach contents of beached Fulmar specimens. The aims of this research were to: firstly set a baseline investigation of multispecies of seabirds in Ireland affected by the ingestion of litter and, secondly to investigate the feasibility of using Fulmar and/or other potential species of seabird as an indicator for marine debris in Ireland through beached bird surveys. Within 30 months, 121 birds comprising 16 different species were collected and examined for the presence of litter. Of these, 27.3% (n = 33) comprising 12 different species were found to ingest litter, mainly plastics. The average mass of ingested litter was 0.141 g. Among 14 sampled Northern Fulmars, 13 (93%) had ingested plastic litter, all of them over the 0.1 g threshold used in OSPAR and MSFD policy target definitions. Results show that seabirds in Ireland are ingesting marine litter, as in many other countries in the world. Monitoring seabird litter ingestion has the potential to form part of a wider marine litter monitoring programme that can help to inform mitigation and management measures for marine litter.