Seabird transported contaminants are dispersed in island ecosystems.

Seabirds are long-range transporters of nutrients and contaminants, linking marine feeding areas with terrestrial breeding and roosting sites. By depositing nutrient-rich guano, which acts as a fertiliser, seabirds can substantially influence the terrestrial environment in which they reside. However, increasing pollution of the marine environment has resulted in guano becoming similarly polluted. Here, we determined metal and metalloid concentrations (As, Cd, Cr, Cu, Hg, Pb) in Flesh-footed Shearwater (Ardenna carneipes) guano, soil, terrestrial flora, and primary consumers and used an ecological approach to assess whether the trace elements in guano were bioaccumulating and contaminating the surrounding environment. Concentrations in guano were higher than those of other Procellariiformes documented in the literature, which may be influenced by the high amounts of plastics that this species of shearwater ingests. Soil samples from shearwater colonies had significantly higher concentrations of all metals, except for Pb, than soils from control sites and formerly occupied areas. Concentrations in terrestrial primary producers and primary consumers were not as marked, and for many contaminants there was no significant difference observed across levels of ornithogenic input. We conclude that Flesh-footed Shearwaters are transporters of marine derived contaminants to the Lord Howe Island terrestrial environment.

Plastic ingestion and trace element contamination of Manx shearwaters Puffinus puffinus on the Faroe Islands.

Procellariiform seabirds can accumulate high levels of plastic in their gastrointestinal tracts, which can cause physical damage and potentially provides a contamination route for trace elements. We examined plastic ingestion and trace element contamination of fledgling Manx shearwaters Puffinus puffinus that were harvested for human consumption in 2003 and 2018 on Skúvoy, Faroe Islands (North Atlantic Ocean). Overall, 88% of fledglings contained plastic in their gastrointestinal tracts, with a mean (± SD) of 7.2 ± 6.6 items weighing 0.007 ± 0.016 g. Though the incidence was similar, fledglings ingested significantly more plastic in 2018 compared to 2003. Hepatic trace element concentrations were unrelated to plastic ingestion. Hepatic carbon (δ13C) and nitrogen (δ15N) stable isotope values were significantly lower in birds sampled in 2018 versus 2003, potentially reflecting further offshore feeding at lower trophic levels. Future research is needed to understand the extent of plastic ingestion by Faroe Islands seabirds.

Biochemical and molecular biomarkers and their association with anthropogenic chemicals in wintering Manx shearwaters (Puffinus puffinus).

Anthropogenic pollution poses a threat to marine conservation by causing chronic toxic effects. Seabirds have contact throughout their lives with pollutants like plastic, metals, polychlorinated biphenyls (PCBs), and organochlorine pesticides such as hexachlorocyclohexanes (HCHs). We assessed 155 Manx shearwaters (Puffinus puffinus) stranded along the Brazilian coast, analyzing associations between organic pollutants, plastic ingestion, biomarkers (transcript levels of aryl hydrocarbon receptor, cytochrome P450-1A-5 [CYP1A5], UDP-glucuronosyl-transferase [UGT1], estrogen receptor alpha-1 [ESR1], and heat shock protein-70 genes) and enzymes activity (ethoxy-resorufin O-deethylase and glutathione S-transferase [GST]). Plastic debris was found in 29 % of the birds. The transcription of UGT1 and CYP1A5 was significantly associated with hexachlorobenzene (HCB) and PCBs levels. ESR1 was associated with HCB and Mirex, and GST was associated with Drins and Mirex. While organic pollutants affected shearwaters more than plastic ingestion, reducing plastic availability remains relevant as xenobiotics are also potentially adsorbed onto plastics.

New insights into avian malaria infections in New Zealand seabirds.

The past few years have been marked by a drastic increase in pathogen spillover events. However, the extent and taxonomic range at which these events take place remain as crucial unanswered questions in many host-pathogen systems. Here, we take advantage of opportunistically sampled bird carcasses from the South Island of New Zealand, with the aim of identifying Plasmodium spp. infections in native and endemic New Zealand seabird species. In total, six samples from five bird species were positive for avian malaria, including four of which were successfully sequenced and identified as Plasmodium matutinum LINN1 lineage. These results provide new Plasmodium infection records in seabirds, including the first documented case in Procellariiformes in New Zealand, highlighting the potential disease risk to these species.

Patterns of recovery in extant and extirpated seabirds after the world's largest multipredator eradication.

Eradicating invasive predators from islands can result in substantial recovery of seabirds, but the mechanisms that drive population changes remain poorly understood. Meta-analyses have recently revealed that immigration is surprisingly important to the recovery of philopatric seabirds, but it is not known whether dispersal and philopatry interact predictably to determine rates of population growth and changes of distribution. We used whole-island surveys and long-term monitoring plots to study the abundance, distribution, and trends of 4 burrowing seabird species on Macquarie Island, Australia, to examine the legacy impacts of invasive species and ongoing responses to the world's largest eradication of multiple species of vertebrates. Wekas (Gallirallus australis) were eradicated in 1988; cats (Felis catus) in 2001; and rabbits (Oryctolagus cuniculus), black rats (Rattus rattus), and mice (Mus mus) in 2011-2014. We compared surveys from 1976-1979 and 2017-2018 and monitoring from the 1990s and 2000s onward. Antarctic prions (Pachyptila desolata) and white-headed petrels (Pterodroma lessonii) increased ∼1% per year. Blue petrels (Halobaena caerulea) and gray petrels (Procellaria cinerea) recolonized following extirpation from the main island in the 1900s but remained spatially and numerically rare in 2018. However, they increased rapidly at 14% and 10% per year, respectively, since cat eradication in 2001. Blue and gray petrel recolonization occurred on steep, dry, west-facing slopes close to ridgelines at low elevation (i.e., high-quality petrel habitat). They overlapped <5% with the distribution of Antarctic prion and white-headed petrels which occurred in suboptimal shallow, wet, east-facing slopes at high elevation. We inferred that the speed of population growth of recolonizing species was related to their numerically smaller starting size compared with the established species and was driven by immigration and selection of ideal habitat.

Patrones de recuperación en aves marinas existentes y extirpadas después de la mayor erradicación mundial de multidepredadores Resumen La erradicación de depredadores invasores en las islas puede derivar en la recuperación sustancial de aves marinas, aunque entendemos muy poco los mecanismos que causan los cambios poblacionales. Los metaanálisis recientes han revelado que la inmigración es de gran importancia para la recuperación de aves marinas filopátricas, aunque no sabemos si la dispersión y la filopatría interactúan de forma predecible para poder determinar las tasas de crecimiento poblacional y los cambios en la distribución. Aplicamos censos de isla completa y parcelas de monitoreo a largo plazo para estudiar la abundancia, distribución y tendencias de cuatro especies de aves marinas cavadoras en la Isla Macquarie, Australia, para analizar los impactos heredados de las especies invasoras y la respuesta continua a la mayor erradicación mundial de varias especies de vertebrados. El rascón weka (Gallirallus australis) se erradicó en 1988; los gatos (Felis catus) en 2001; y los conejos (Oryctolagus cuniculus), ratas (Rattus rattus) y ratones (Mus mus) entre 2011 y 2014. Comparamos los censos de 1976­1979 y 2017­2018 y el monitoreo realizado en los 90s y del año 2000 en adelante. El pato petrel antártico (Pachyptila desolata) y el petrel cabeciblanco (Pterodroma lessonii) incrementaron ∼1% por año. El petrel azulado (Halobaena caerulea) y la pardela gris (Procellaria cinerea) recolonizaron la isla después de su extirpación en la década de 1900, pero todavía eran especies raras espacial y numéricamente en 2018. Sin embargo, esta especie incrementó rápidamente en un 14% y 10% por año respectivamente desde que se erradicaron los gatos en 2001. La recolonización ocurrió desde las laderas empinadas, secas y con orientación al oeste en los sistemas montañosos de baja elevación (es decir, hábitats de gran calidad para los petreles). La distribución del petrel azulado y la pardela gris ocurrió en laderas someras subóptimas y húmedas con orientación al este a altas elevaciones. Esta distribución se traslapó menos del 5% con la del pato petrel antártico y la del petrel cabeciblanco. Inferimos que la velocidad del crecimiento poblacional de las especies que recolonizaron estuvo relacionada con el menor tamaño inicial en comparación con las especies establecidas y fue causada por la inmigración y la selección del hábitat ideal.

Whole-genome Analyses Reveal Past Population Fluctuations and Low Genetic Diversities of the North Pacific Albatrosses.

Throughout the Plio-Pleistocene, climate change has impacted tropical marine ecosystems substantially, with even more severe impacts predicted in the Anthropocene. Although many studies have clarified demographic histories of seabirds in polar regions, the history of keystone seabirds of the tropics is unclear, despite the prominence of albatrosses (Diomedeidae, Procellariiformes) as the largest and most threatened group of oceanic seabirds. To understand the impact of climate change on tropical albatrosses, we investigated the evolutionary and demographic histories of all four North Pacific albatrosses and their prey using whole-genome analyses. We report a striking concordance in demographic histories among the four species, with a notable dip in effective population size at the beginning of the Pleistocene and a population expansion in the Last Glacial Period when sea levels were low, which resulted in increased potential coastal breeding sites. Abundance of the black-footed albatross dropped again during the Last Glacial Maximum, potentially linked to climate-driven loss of breeding sites and concordant genome-derived decreases in its major prey. We find very low genome-wide (π < 0.001) and adaptative genetic diversities across the albatrosses, with genes of the major histocompatibility complex close to monomorphic. We also identify recent selective sweeps at genes associated with hyperosmotic adaptation, longevity, and cognition and memory. Our study has shed light on the evolutionary and demographic histories of the largest tropical oceanic seabirds and provides evidence for their large population fluctuations and alarmingly low genetic diversities.

Pelagic and estuarine birds as sentinels of metal(loid)s in the South Atlantic Ocean: Ecological niches as main factors acting on bioaccumulation.

Activities related to the offshore exploration and production of oil and natural gas provide economic development and an essential energy source. However, besides the risk of petroleum hydrocarbon contamination, these activities can also be sources of metals and metalloids for marine organism contamination. In this research, we evaluated the potential use of two pelagic (black-browed albatross Thalassarche melanophris and yellow-nosed albatross T. chlororhynchos) and one estuarine bird species (neotropical cormorant Nannopterum brasilianus) as sentinels of contamination of As, Cd, Cr, Cu, Pb, Mn, Mo, Zn, Ni, Ba, V, and Hg in an area under influence of oil and gas activities. The analyses were carried out in samples collected from 2015 to 2022 from 97 individuals. A factor alert; an adaptation from the contamination factor is proposed to identify individuals with high concentrations that possibly suffered contamination by anthropogenic origin. Grouping all species, the metal(loid)s with the highest concentrations were in decreasing order: Zn > Cu > Mn > Hg > As > Cd > Mo > V > Cr > Ba > Ni > Pb. Similar concentrations were observed for V, Mn, Cr and Pb among the three species. Pelagic birds showed higher levels of concentrations for Hg, As and Cd. Based on the correlations and multivariate analysis performed, the results indicate that the ecological niche factor has greater relevance in the bioaccumulation of these elements compared to the habitat. Although some individuals showed high concentrations in part of the trace elements, suggesting exposure to anthropic sources, the direct influence of oil production and exploration activities was not observed, suggesting that activities on the continent are the primary contamination source. The results of this work highlight the role of seabirds as sentinels for metal(loid)s, contributing to the knowledge of the occurrence of contaminants in the South Atlantic Ocean.

Ontogenetic exposure to light influences seabird vulnerability to light pollution.

Light pollution critically affects fledglings of burrow-nesting seabirds, leading to massive mortality events. The successful management of this pollutant depends upon a comprehensive understanding of the factors influencing visual sensitivity and corresponding behaviours towards light. Factors shaping the development of the visual system could account for variation in seabirds' vulnerability to light pollution. We investigated how Cory's shearwater chicks respond to selected contrasting artificial light stimuli. Chicks were subjected to blue and red light treatments, and repeatedly tested throughout the nestling period. We analysed behavioural responses (number, timing and orientation of reactions) to determine how age, exposure to experimental light stimuli and spectra influenced the onset of visually guided behaviours, thus inferring drivers of vulnerability to light pollution. Repetitive exposure to light significantly increased the number of reactions, and chicks predominantly displayed light avoidance behaviour. We did not find differences in the number of reactions, timing and orientation between blue and red light treatments. The responses did not differ across different age groups. These results provide empirical evidence for the contribution of the light available in the rearing environment to seabird visual development. They support the hypothesis that differential exposure to light during the growth period influences responses to artificial light, and that the state of visual development at fledging could be a main driver of the age bias observed during seabird fallout events. It is thus important to evaluate lighting schemes in both urban and natural areas, and determine the as yet unknown consequences that may be affecting the populations.

Can the mass of plastic ingested by seabirds be predicted by the number of ingested items?

Plastics pollution has been documented for decades, yet repeatable methods for evaluating quantities are lacking. For wildlife, the mass and number of ingested plastics are widely reported, but these are not without their challenges, especially in field settings. Rapid methods for estimating the mass of ingested plastic could therefore be useful, but the relationship with the number of ingested pieces has not been explored. Using a dataset covering 1278 individuals of 11 Procellariiform species, we investigated this relationship to determine if counts could act as a proxy for the mass of ingested plastic by seabirds. Larger species ingested larger pieces of plastic, and birds that consumed more pieces also ingested items that are physically larger. Across species, sample size significantly influenced the slope of the relationship between the mass and number of ingested plastics. The mass-number relationship is species-specific, highly driven by sample size, and varies temporally.

Implications of Regurgitative Feeding on Plastic Loads in Northern Fulmars (Fulmarus glacialis): A Study from Svalbard.

Procellariiform seabirds like northern fulmars (Fulmarus glacialis) are prone to ingest and accumulate floating plastic pieces. In the North Sea region, there is a long tradition to use beached fulmars as biomonitors for marine plastic pollution. Monitoring data revealed consistently lower plastic burdens in adult fulmars compared to younger age classes. Those findings were hypothesized to partly result from parental transfer of plastic to chicks. However, no prior study has examined this mechanism in fulmars by comparing plastic burdens in fledglings and older fulmars shortly after the chick-rearing period. Therefore, we investigated plastic ingestion in 39 fulmars from Kongsfjorden (Svalbard), including 21 fledglings and 18 older fulmars (adults/older immatures). We found that fledglings (50-60 days old) had significantly more plastic than older fulmars. While plastic was found in all fledglings, two older fulmars contained no and several older individuals barely any plastic. These findings supported that fulmar chicks from Svalbard get fed high quantities of plastic by their parents. Adverse effects of plastic on fulmars were indicated by one fragment that perforated the stomach and possibly one thread perforating the intestine. Negative correlations between plastic mass and body fat in fledglings and older fulmars were not significant.

High-Performance PCR for Alleles Discrimination of Chromo-Helicase-DNA Binding Protein (CHD1) Gene in Bird Sexing.

Genetic analyses aiming at assessing the presence of specific sequences or alleles are often carried out by PCR. Sexing of most birds is nowadays based on PCR with "universal" primers and relies on the assessment of the presence of the sex-linked CHD1-Z and -W alleles. The entire workflow is relatively time-consuming, especially for batch analyses, whereas methods that allow carrying out the entire procedure in a short time are highly desirable. The only method for outdoor analyses reported so far relies on LAMP; however; it fails to work properly in Procellariiformes. Besides improving the LAMP test; we have developed a PCR-based DNA amplification procedure (named high-performance PCR); whose unique features allow it to outperform standard PCR; making possible the direct, in-tube visual reading of results. We tested it with specifically designed Procellariiformes-targeted primer sets for rapid sexing of the birds using fluorimetric detection. The protocol, combined with rapid DNA extraction, allows for fast reading of results without electrophoresis within less than 1 h from sampling. The technique could be extended to other species, as well as to many other applications.

The First Genome of the Balearic Shearwater (Puffinus mauretanicus) Provides a Valuable Resource for Conservation Genomics and Sheds Light on Adaptation to a Pelagic lifestyle.

The Balearic shearwater (Puffinus mauretanicus) is the most threatened seabird in Europe and a member of the most speciose group of pelagic seabirds, the order Procellariiformes, which exhibit extreme adaptations to a pelagic lifestyle. The fossil record suggests that human colonisation of the Balearic Islands resulted in a sharp decrease of the Balearic shearwater population size. Currently, populations of the species continue to be decimated mainly due to predation by introduced mammals and bycatch in longline fisheries, with some studies predicting its extinction by 2070. Here, using a combination of short and long reads, we generate the first high-quality reference genome for the Balearic shearwater, with a completeness amongst the highest across available avian species. We used this reference genome to study critical aspects relevant to the conservation status of the species and to gain insights into the adaptation to a pelagic lifestyle of the order Procellariiformes. We detected relatively high levels of genome-wide heterozygosity in the Balearic shearwater despite its reduced population size. However, the reconstruction of its historical demography uncovered an abrupt population decline potentially linked to a reduction of the neritic zone during the Penultimate Glacial Period (∼194-135 ka). Comparative genomics analyses uncover a set of candidate genes that may have played an important role into the adaptation to a pelagic lifestyle of Procellariiformes, including those for the enhancement of fishing capabilities, night vision, and the development of natriuresis. The reference genome obtained will be the crucial in the future development of genetic tools in conservation efforts for this Critically Endangered species.

Seabird stress and breeding: Endocrine and hematological stress biomarkers differ between gray-faced petrel (Pterodroma gouldi) colonies.

Seabird breeding success is known to reflect oceanic conditions. Gray-faced petrels (Pterodroma gouldi) breeding on the east coast of Auckland, New Zealand, exhibit poor reproductive success and slow chick development compared to west coast conspecifics. This study mapped changes in physiological traits (corticosterone [CORT] and hematological parameters) indicative of sublethal stress in this Procellariiform species between the west coast (Ihumoana) and east coast (Hawere) island colonies. We found adult gray-faced petrels on the east coast to be lighter and, unlike west coast birds, exhibited an attenuation of response CORT levels between incubation and chick-rearing phases. Such responses were also reflected in east coast chicks that were lighter and had higher feather CORT titers than west coast chicks. Measures of adult hematology and plasma biochemistry revealed significantly lower glucose levels in east coast birds and indicated that chick rearing is the most stressful phase of breeding for this species Combined; these results suggest that east coast birds are under greater nutritional stress and that parents appear to transfer the costs of poor foraging to their chicks to preserve their own condition, consequently increasing chick developmental stress. Our results suggest that any long-term decrease in ocean conditions and/or climatic shifts would be more acutely felt by east coast chicks and potentially their parents, resulting in years of poor breeding success rates on a local scale.

Independent evolution of intermediate bill widths in a seabird clade.

Interspecific introgression can occur between species that evolve rapidly within an adaptive radiation. Pachyptila petrels differ in bill size and are characterised by incomplete reproductive isolation, leading to interspecific gene flow. Salvin's prion (Pachyptila salvini), whose bill width is intermediate between broad-billed (P. vittata) and Antarctic (P. desolata) prions, evolved through homoploid hybrid speciation. MacGillivray's prion (P. macgillivrayi), known from a single population on St Paul (Indian Ocean), has a bill width intermediate between salvini and vittata and could also be the product of interspecies introgression or hybrid speciation. Recently, another prion population phenotypically similar to macgillivrayi was discovered on Gough (Atlantic Ocean), where it breeds 3 months later than vittata. The similarity in bill width between the medium-billed birds on Gough and macgillivrayi suggest that they could be closely related. In this study, we used genetic and morphological data to infer the phylogenetic position and evolutionary history of P. macgillivrayi and the Gough medium-billed prion relative other Pachyptila taxa, to determine whether species with medium bill widths evolved through common ancestry or convergence. We found that Gough medium-billed prions belong to the same evolutionary lineage as macgillivrayi, representing a new population of MacGillivray's prion that originated through a colonisation event from St Paul. We show that macgillivrayi's medium bill width evolved through divergence (genetic drift) and independently from that of salvini, which evolved through hybridisation (gene flow). This represents the independent convergence towards a similarly medium-billed phenotype. The newly discovered MacGillivray's prion population on Gough is of utmost conservation relevance, as the relict macgillivrayi population in the Indian Ocean is very small.

Ingestion of plastics and other debris by coastal and pelagic birds along the coast of Espírito Santo, Eastern Brazil.

Although the ingestion of plastics and other anthropogenic debris by seabirds is a global problem, few studies have employed standardized protocols to quantify and classify the debris ingested by seabirds in the Southwest Atlantic. We evaluated the ingestion of marine debris (items >0.1 mm) by 126 coastal and pelagic birds (19 species) along the coast of Espírito Santo, Eastern Brazil. Debris were found in 30% of birds examined (11 species). Particles <1 mm accounted for 35% of all debris items. Most ingested debris were plastics (97%). Ingestion of >0.1 g of plastic debris was recorded in five species: Atlantic yellow-nosed albatrosses (Thalassarche chlororhynchos), Cory's shearwaters (Calonectris borealis), Manx shearwaters (Puffinus puffinus), brown boobies (Sula leucogaster), and Magellanic penguins (Spheniscus magellanicus). Our findings suggest that the ingestion of marine debris, especially plastics, is a common problem for coastal and pelagic birds in tropical Southwest Atlantic waters.

PATHOLOGY OF NORTHERN FULMARS (FULMARUS GLACIALIS) AND SHEARWATERS BEACHED ON SABLE ISLAND, NOVA SCOTIA, CANADA.

Marine birds are frequently found dead on beaches, either from natural or from anthropogenic causes. Complete necropsies of those carcasses can provide valuable information, particularly for pelagic species, such as Northern Fulmars (Fulmarus glacialis) and shearwaters, which come to land only to breed and for which information on diseases that may affect them is, therefore, sparse. Between 2000 and 2012, 315 carcasses of four species of Procellariiformes (173 Northern Fulmars, 89 Great Shearwaters [Ardenna gravis], 50 Sooty Shearwaters [Ardenna grisea], and three Cory's Shearwaters [Calonectris diomedea]) were collected on Sable Island, Nova Scotia, Canada, an isolated island near the edge of the continental shelf. A complete necropsy, including examination for the presence of ingested plastic, was performed on all carcasses. Most (70%) of these birds were immature. The cause of death was undetermined in 22% (n=70) of the birds: 36% (62/173) of the Northern Fulmars, 4% (4/89) of the Great Shearwaters, 6% (3/50) of the Sooty Shearwaters, and 33% (1/3) of the Cory's Shearwaters. Emaciation was considered the primary cause of death in 91% of the remaining 245 birds: 87% (97/111) of the Northern Fulmars, 92% (78/85) of the Great Shearwaters, 100% (47/47) of the Sooty Shearwaters, and 100% (2/2) of the Cory's Shearwaters. Notable primary causes of death other than emaciation included mycobacteriosis and neoplasia in Northern Fulmars and transmural parasitic proventriculitis in Great Shearwaters. For Northern Fulmars, nutritional condition (as determined semiquantitatively) was compared with other parameters. Birds in good nutritional condition had heavier body mass and flight muscle mass than those in poor nutritional condition (P<0.01). More adults were in poor nutritional condition than expected by chance (91%; χ2=8.23, P<0.01), whereas only 57% of immature birds were in poor condition. There was no relationship between nutritional condition and sex or mass of ingested plastic. Our study provides information on some previously unsuspected health threats in Procellariiformes.

Ingested plastics in northern fulmars (Fulmarus glacialis): A pathway for polybrominated diphenyl ether (PBDE) exposure?

Although it has been suggested that plastic may act as a vector for pollutants into the tissue of seabirds, the bioaccumulation of harmful contaminants, such as polybrominated diphenyl ethers (PBDEs), released from ingested plastics is poorly understood. Plastic ingestion by the procellariiform species northern fulmar (Fulmarus glacialis) is well documented. In this study, we measured PBDEs levels in liver tissue of northern fulmars without and with (0.13-0.43 g per individual) stomach plastics. PBDE concentrations in the plastic sampled from the same birds were also quantified. Birds were either found dead on beaches in southern Norway or incidentally caught in longline fisheries in northern Norway. PBDEs were detected in all birds but high concentrations were only found in liver samples from beached birds, peaking at 2900 ng/g lipid weight. We found that body condition was a significant factor explaining the elevated concentration levels in livers of beached birds. BDE209 was found in ingested plastic particles and liver tissue of birds with ingested plastics but was absent in the livers of birds without ingested plastics. This strongly suggests a plastic-derived transfer and accumulation of BDE209 to the tissue of fulmars, levels of which might prove useful as a general indicator of plastic ingestion in seabirds.

Polymer types ingested by northern fulmars (Fulmarus glacialis) and southern hemisphere relatives.

Although ingestion of plastic by tubenosed seabirds has been documented regularly, identification of the polymer composition of these plastics has rarely been described. Polymer assessment may assist in identifying sources and may indicate risks from additives occurring in specific types of polymers. Using known test materials, two identification methods Fourier transform infrared spectroscopy and near infrared spectroscopy (FTIR and NIR) were compared. Although both methods were found to be similarly suitable for identification of plastic polymers, a significant difference was observed in identification of natural materials. FTIR frequently misclassified natural materials as being a synthetic polymer. Within our results, an 80% match score threshold functioned best to distinguish between natural items and synthetics. Using NIR, the historical variability of plastics ingested by northern fulmars (Fulmarus glacialis) from the Dutch sector of the North Sea was analysed for three time periods since the 1980s. For the more recent decade, variability between fulmars from different regions in the northeast Atlantic was investigated. Regional variation was further explored by analysing plastics obtained from the stomachs of southern hemisphere relatives of the fulmar (southern fulmar, cape petrel, snow petrel) and Wilson's storm petrel. Results show that proportional abundance of polymer types in these seabirds is closely related to the plastic categories that they ingest (e.g. pellets, foam, fragments). The uptake of different plastic categories and related polymer types most likely reflects spatial and temporal variations in availability rather than ingestion preferences of the birds.

Staphylococcus sciuri as a Reservoir of mecA to Staphylococcus aureus in Non-Migratory Seabirds from a Remote Oceanic Island.

Aim: Genomic analysis of a methicillin-resistant Staphylococcus aureus (MRSA) strain cultured from a non-migratory seabird at Fernando de Noronha Archipelago (Brazilian oceanic islands) was carried out to investigate the potential origin of MRSA genetic determinants in an ecological setting with minimal or absent antimicrobial selective pressure, and minimal interaction with humans and domestic animals. Results: The study determined mecA gene homology and the phylogenetic relatedness with mecA described in Staphylococcus sciuri, which was the major Staphylococcus spp. cultured from the birds. Our findings corroborate in silico assumptions that the mecA gene in MRSA strains clinically relevant for humans and animals originates from S. sciuri ancestors. Conclusion: Coagulase-negative staphylococci seem to be natural reservoirs of methicillin-resistant genes to S. aureus, even in environments with very low antimicrobial selection pressure.

Decadal changes in plastic litter regurgitated by albatrosses and giant petrels at sub-Antarctic Marion Island.

Plastic ingestion by seabirds is an efficient way to monitor marine plastics. We report temporal variation in the characteristics of marine litter regurgitated by albatrosses and giant petrels on sub-Antarctic Marion Island between 1996 and 2018. Both fishery and other litter peaked during the height of the Patagonian toothfish fishery around the island (1997-1999). Comparing the two subsequent decades of reduced fishing effort (1999-2008 and 2009-2018), fishing litter decreased while other litter increased across all species. Litter increased most in grey-headed albatrosses, followed by giant petrels and wandering albatrosses. Similar ranked responses were found in the same species at South Georgia, but non-fishery-related litter has increased faster in the Indian Ocean than the southwest Atlantic, indicating regional changes in litter growth rates. These seabirds' regurgitations provide an easy, non-invasive way to track changes in oceanic litter in a remote area that is otherwise difficult to monitor.