Anthropogenic debris ingestion in a tropical seabird community: Insights from taxonomy and foraging distribution

Seabirds in a flap: The ingestion of meso/macro marine debris, microplastics and oil/tar by marine and coastal birds in the United Arab Emirates

This study provides the first published data on the ingestion of solid marine debris, microplastics (MPs), and oil/tar by marine and coastal birds in the Middle East, focusing on the Arabian Gulf and Gulf of Oman coasts of the Sharjah Emirate, UAE. The gastrointestinal tracts of 478 stranded seabirds from 17 species were examined. With the majority of specimens collected being Black-headed Gulls (Chroicocephalus ridibundus; N = 406; 77 juveniles, 326 adults, and 3 unknown) the analysis of their ingested marine debris was done in greatest detail, followed by Socotra Cormorants (Phalacrocorax nigrogularis; N = 23; 7 juveniles, 13 adults and 3 unknown) and large white-headed gulls (Larus sp.; N = 29; 6 juveniles and 23 adults). Across all species marine debris was detected in 12.8 % of specimens, with solid debris found in 11.1 % and oil globules in 1.67 %. Plastics were the most common material ingested by Black headed Gulls, followed by glass. Juvenile Large white-headed gulls ingested significantly more debris than adults. Polyethylene (PE) was the predominant type of plastic ingested. MPs were examined in 20 specimens consisting of 14 Black-headed Gulls and 6 Socotra Cormorants. Most MPs (77.8 %) were microfibers, suggesting wastewater discharge from laundry as a likely source. Interactions with oil globules and fishing hooks posed the greatest acute risk to seabirds. This study highlights the significant impact of marine pollution on seabirds in a previously unexamined region, underscoring the urgent need for targeted conservation efforts to protect vulnerable species in the Middle East.

Characterisation of plastic debris (macro-, meso-, and microplastics) from stranded alcids in southern Spain

Plastic pollution has become a major issue for marine ecosystems. Seabirds are particularly vulnerable to this pollution and are very good indicators of the ecological state of marine ecosystems. This study aims to analyse the presence of plastics in the digestive tracts of two seabird species: the Atlantic puffin (Fratercula arctica) and the razorbill (Alca torda), collected along the Andalusia coast in Southern Spain. A total of 123 carcasses were collected during the autumn and winter seasons of 2022-2024. The results showed a significantly higher presence of plastics in Atlantic puffin (65.0 %) compared to razorbill (18.4 %). The mean number of plastics per puffin was 2.50 ± 2.75, while per razorbill was 0.31 ± 0.94. The predominant type of ingested plastic was fibres in both Atlantic puffin (38.0 %, n = 19) and razorbill (40.6 %, n = 13), with an average size of 1.58 ± 0.74 mm and 2.13 ± 1.98 mm, respectively. The predominant colour was black in both species (22.0 % in puffin and 46.9 % in razorbill), and polyethylene (39.5 %) was the most common plastic polymer, consisting of highly fragmented particles with low levels of adhering heavy metals. This study supports the growing concern about plastic pollution in marine environment, showing that alcid populations are ingesting plastics, potentially threatening these vulnerable species.

Marine litter seen through the lens: photo-identification on beaches as a strategy for coastal monitoring and management

The lack of coastal management leads to economic, social, and environmental problems. In this study, beaches in two municipalities, Laguna and Passo de Torres, located in southern Brazil, were monitored for the presence of marine litter through photographic records. Both beaches experience tourism and fishing activities, with their intensity fluctuating seasonally. Data collection was carried out over the four seasons of the year to assess the density, categories, and spatiotemporal distribution of the debris. A total of 3239 photos were taken across all sampling periods, with the number of photographs per transect varying according to the amount of visible litter. In total, 1694 items were recorded in Passo de Torres and 3935 in Laguna, with an average density of 0.051 and 0.078 items/m2, respectively. Frequency analysis identified six dominant categories of debris per municipality, with five in common: plastic fragments, packaging, plastic bags, cigarette butts, and fishing waste. The only difference was the presence of plastic bottle caps in Laguna and rigid packaging in Passo de Torres. Plastic fragments were the most abundant category, present in all recorded images, with frequencies of occurrence higher than 50 % for both municipalities. Despite seasonal and spatial variations, both beaches were classified as "very clean" throughout the year, according to the Clean Coast Index. These results highlight the need for specific management strategies for each municipality, aiming to mitigate local pollution sources and promote coastal conservation.

From mudflats and saltpans to Open Sea: Plastic ingestion and PBDE/MeO-BDE accumulation in Waterbirds from southern Portugal

Plastic ingestion greatly affects waterbirds, causing lacerations and potentially leading to health disruptions from chemical leaching. Polybrominated diphenyl ethers (PBDEs), used as flame retardants in plastics, remain persistent in the environment despite restrictions, along with the less studied methoxylated PBDEs (MeO-BDEs), that may result from their transformation. Since most plastic pollution in the heavily impacted marine environment comes from terrestrial sources, freshwater/estuarine and coastal environments can also be heavily exposed to contamination. Nonetheless, research in these areas remains limited. We studied the breeding waterbird community from Ria Formosa (Algarve, Portugal) as a proxy of such contamination and sampled the wader species feeding in mudflats and saltpans, little terns feeding in lagoon channels and the adjacent sea, opportunistic gulls feeding mostly on fishery discards and landfills and marine foraging gulls feeding exclusively at sea. Specifically, we assessed 1) plastic ingestion, through the analysis of regurgitations and faeces, and 2) PBDEs and MeO-BDES uptake in eggs, feathers, and preen oil. Results showed that, overall, microplastics were the most commonly detected particles. Yellow-legged gulls (Larus michahellis) and little terns (Sternula albifrons) ingested more particles, especially fibres. Eggs of black-winged stilt (Himantopus himantopus) and yellow-legged gull had higher PBDEs concentrations, while MeO-BDEs did not differ among species. Feathers exhibited low detection values, but MeO-BDEs suggests marine invertebrates' consumption. Little terns accumulated more PBDEs and MeO-BDEs, suggesting an association between plastic ingestion and contamination load. However, species-specific traits, dietary preferences, and foraging areas should also be taken into consideration.

Microplastics in faeces of European shags Gulosus aristotelis in central Norway

Plastic pollution is an increasing problem in the marine environment, and microplastics are frequently ingested by wildlife, including seabirds. Faeces are an increasingly used matrix to quantify egested microplastics. We investigated microplastics in 36 faeces samples from chicks of European shags (Gulosus aristotelis) sampled at Sklinna, central Norway in 2021. Small particles <300 μm (62 %) dominated the material. Out of 465 particles measured with Raman spectroscopy, 32 were identified as microplastics (21 fragments, 4 fibres). 69.4 % of faecal samples contained microplastics, with on average 17 microplastic particles per g faeces dry weight. Sixteen of the 36 samples originated from siblings sampled within the same hour, and plastic loads of these samples were more similar to each other compared to those from other individuals. This suggests that a sample from one chick is representative for all siblings at a given moment in time and proofs parental transfer of MP.

Influence of paternal factors on plastic ingestion and brominated chemical exposure in East Tropical Atlantic Procellariid chicks

The presence of plastic debris and organo-brominated compounds in the marine environment poses a concern to wildlife. Plastic can absorb and release chemical compounds, making their ingestion potentially harmful, while chemical compounds have become omnipresent, with a tendency to bioaccumulate in the food web. Seabirds are often used as indicators of marine plastic pollution, yet studies on the exposure of tropical communities to plastic contamination are still scarce. In this study we monitored the amounts of plastics in faeces and organo-brominated compounds ingested/assimilated in feathers by adults and chicks of Cape Verde shearwaters and Bulwer's petrels from Cabo Verde. Anthropogenic pollutants, polybrominated diphenyl ethers (PBDEs), and naturally generated methoxylated-PBDEs (MeO-PBDEs) were among the probed compounds. The frequency of plastic debris ingestion was similar in both species' adults and chicks, although, the characteristics of the ingested plastic differed. Frequency and number of microplastics increased throughout the nestling season for chicks from both species. All species and age groups showed the presence of PBDEs and MeO-PBDEs. Among PBDEs, Bulwer's petrels exhibited higher concentrations than Cape Verde shearwaters, and chicks had higher concentration profiles than adults. Specifically, Bulwer's petrel chicks showed higher concentrations than Cape Verde shearwater chicks. On the contrary, Cape Verde shearwater adults exhibited higher occurrence and concentrations of MeO-PBDEs when compared to Cape Verde shearwater chicks. We found no effect of plastic loadings or loadings of organohalogen contaminants on body condition or size, although harmful effects may be hidden or reveal themselves in a medium- to long-term. Feather samples from both adults and chicks were shown to be useful for comparing intraspecific contamination levels and appear suitable for the long-term assessment of organohalogen contaminants in seabirds. Species-specific foraging and feeding strategies are likely the drivers of the observed variation in organochlorine contamination burdens among seabird species.

Lost and found: Patterns of marine litter accumulation on the remote Island of Santa Luzia, Cabo Verde

Santa Luzia, an uninhabited island in the archipelago of Cabo Verde, serves as a natural laboratory and important nesting site for loggerhead turtles Carettacaretta. The island constitutes an Integral Natural Reserve and a Marine Protected Area. We assessed marine litter accumulation on sandy beaches of the island and analysed their spatial patterns using two sampling methods: at a fine scale, sand samples from 1 × 1 m squares were collected, identifying debris larger than 1 mm; at a coarse scale, drone surveys were conducted to identify visible marine debris (>25 mm) in aerial images. We sampled six points on three beaches of the island: Achados (three points), Francisca (two points) and Palmo Tostão (one point). Then, we modelled the abundance of marine debris using topographical variables as explanatory factors, derived from digital surface models (DSM). Our findings reveal that the island is a significant repository for marine litter (>84% composed of plastics), with up to 917 plastic items per m2 in the sand samples and a maximum of 38 macro-debris items per m2 in the drone surveys. Plastic fragments dominate, followed by plastic pellets (at the fine-scale approach) and fishing materials (at the coarse-scale approach). We observed that north-facing, higher-elevation beaches accumulate more large marine litter, while slope and elevation affect their spatial distribution within the beach. Achados Beach faces severe marine debris pollution challenges, and the upcoming climate changes could exacerbate this problem.

Microplastics ingestion and endocrine disrupting chemicals (EDCs) by breeding seabirds in the east tropical Atlantic: Associations with trophic and foraging proxies (δ15N and δ13C)

In this study we found that endocrine disrupting chemicals (EDCs) were omnipresent in a tropical seabird community comprising diverse ecological guilds and distinct foraging and trophic preferences. Because EDCs tend to bioaccumulate within the food web and microplastics can absorb and release harmful chemical compounds, our findings draw attention to the potential threats to wildlife. Thus, the goal of this study was to investigate the role of plastic ingestion, trophic and foraging patterns (δ15N and δ13C) of five tropical seabird species breeding in sympatry, on the exposure to EDCs, namely Polybrominated diphenyl ethers (PBDEs), methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and personal care products (PCPs, e.g., musk fragrances and UV-filters). Results indicated that microplastics occurrence and EDCs detection frequency varied among species. Microplastics occurrence was higher in species with dual and coastal foraging strategies. Preen oil had higher levels of MeO-PBDEs and PCPs, while serum had higher levels of PBDEs. In brown boobies, the correlation between microplastics and ∑PBDEs levels was significant, suggesting that microplastics ingestion is a key PBDEs route. Trophic position (δ15N) plays a key role in PBDEs accumulation, particularly in Bulwer's petrel, which occupies a high trophic position and had more specialized feeding ecology than the other species. MeO-PBDEs were linked to foraging habitat (δ13C), although the link to foraging locations deserves further investigation. Overall, our findings not only fill key gaps in our understanding of seabirds' exposure to microplastics and EDCs, but also provide an essential baseline for future research and monitoring efforts. These findings have broader implications for the marine wildlife conservation and pollution management in sensitive environments, such as the tropical regions off West Africa.

Environmental effects from petroleum product transportation spillage in Nigeria: a critical review

Nigeria has struggled to meet sustainable development goals (SDGs) on environmental sustainability, transportation, and petroleum product distribution for decades, endangering human and ecological health. Petroleum product spills contaminate soil, water, and air, harming humans, aquatic life, and biodiversity. The oil and gas industry contributes to environmental sustainability and scientific and technological advancement through its supply chain activities in the transport and logistics sectors. This paper reviewed the effects of petroleum product transportation at three accident hotspots on Nigeria highway, where traffic and accident records are alarming due to the road axis connecting the southern and northern regions of the country. The preliminary data was statistically analysed to optimise the review process and reduce risk factors through ongoing data monitoring. Studies on Nigeria's petroleum product transportation spills and environmental impacts between the years 2013 and 2023 were critically analysed to generate updated information. The searches include Scopus, PubMed, and Google Scholar. Five hundred and forty peer-reviewed studies were analysed, and recommendations were established through the conclusions. The findings show that petroleum product transport causes heavy metal deposition in the environment as heavy metals damage aquatic life and build up in the food chain, posing a health risk to humans. The study revealed that petroleum product spills have far-reaching environmental repercussions and, therefore, recommended that petroleum product spills must be mitigated immediately. Furthermore, the study revealed that better spill response and stricter legislation are needed to reduce spills, while remediation is necessary to lessen the effects of spills on environmental and human health.

Microplastics in feces and pellets from yellow-legged gull (Larus michahellis) in the Atlantic Islands National Park of Galicia (NW Spain)

The Atlantic Islands National Park (AINP) in Galicia (NW of Spain) are host to large colonies of yellow-legged gulls (Larus michahellis). Here, we aimed to provide baseline data for the presence of microplastics (MP) in feces and pellets regurgitated of these resident yellow-legged gulls within this unique ecosystem. MP particles found in the samples were of five shapes (fiber, fragment, foam, film and rubber) and the predominant color was blue. The main plastic polymers identified by Raman spectroscopy were polypropylene and cellulose. The average size of the MP particles in the regurgitations was larger than that in the feces. Considering the population of Larus michahellis in the AINP, our estimates suggested an annual deposition of approximately 32.2 million of MP particles from feces and regurgitated pellets in the area.