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1.
Sci Total Environ ; 927: 172235, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582125

RESUMO

Plastic pollution is a global challenge that affects all marine ecosystems, and reflects all types of uses and activities of human society in these environments. In marine ecosystems, microplastics and mesoplastics interact with invertebrates and become available to higher predators, such as fish, which can ingest these contaminants. This study aimed to analyze how ecological food interactions (diet overlap and trophic niche amplitude) among fish species contribute to the ingestion of plastic particles. The gastrointestinal contents of six fish species (Atherinella brasiliensis, Eucinostomus melanopterus, Eucinostomus argenteus, Genidens genidens, Coptodon rendalli, and Geophagus brasiliensis) were analyzed to identify prey items and plastic ingestion. Based on the ontogenetic classification, A. brasiliensis, E. melanopterus, and G. genidens were divided into juveniles and adults, and the six fish species analyzed were divided into nine predator groups. Most of the plastics ingested by the fish species were blue microplastic (MP) fibers (< 0.05 mm) classified as polyester terephthalate, polyethylene, and polybutadiene. Considering all the analyzed predators, the average number and weight of plastics ingested per individual were 2.01 and 0.0005 g, respectively. We observed that predators with a high trophic overlap could present a relationship with the intake of MP fibers owing to predation on the same resources. In addition, we observed the general pattern that when a species expands its trophic diversity and niche, it can become more susceptible to plastic ingestion. For example, the species with the highest Levin niche amplitude, E. argenteus juveniles, had the highest mean number (2.9) of ingested MP fibers. Understanding the feeding ecology and interactions among species, considering how each predator uses habitats and food resources, can provide a better understanding of how plastic particle contamination occurs and which habitats are contaminated with these polluting substances.


Assuntos
Monitoramento Ambiental , Peixes , Cadeia Alimentar , Microplásticos , Poluentes Químicos da Água , Animais , Peixes/fisiologia , Poluentes Químicos da Água/análise , Conteúdo Gastrointestinal/química , Plásticos/análise , Ecossistema
2.
Aquat Toxicol ; 269: 106867, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432024

RESUMO

Sea turtle mortality is often related to materials that reach the coast from different anthropic activities worldwide. This study aimed to investigate whether sea turtle mortality was related to older marine problems, such as solid waste, or one of the largest oil spill accidents on the Brazilian coast, that occurred in 2019. We posed three questions: 1) Are there solid residues in the digestive tract samples, and which typology is the most abundant? 2) Can meso­ and macro-waste marine pollutants cause mortality? 3) Is the dark material found really oil? A total of 25 gastrointestinal content (GC) samples were obtained, of which 22 ingested waste of anthropogenic origin and 18 were necropsied. These 22 samples were obtained during or after the 2019 oil spill, of which 17 specimens were affected, making it possible to suggest oil ingestion with the cause of death in the animals that could be necropsied. Macroscopic data showed that the most abundant solid waste was plastic (76.05 %), followed by fabrics (12.18 %) and oil-like materials. However, chemical data confirmed only three specimens with oil levels ranging from remnants to high. It was possible to infer possible causes of death in 16 of the total 18 necropsied cases: Most deaths were due to respiratory arrest (62.5 %), followed by pulmonary edema (12.5 %), cachexia syndrome (12.5 %), circulatory shock (6.25 %), and head trauma (6.25 %), which may have been caused by contact with solid waste, oil, or both. The study showed that not all dark material found in the GCs of turtles killed in oiled areas is truly oil, and in this sense, a chemical analysis step to prove the evidence of oil must be added to international protocols.


Assuntos
Poluição por Petróleo , Tartarugas , Poluentes Químicos da Água , Animais , Poluição por Petróleo/efeitos adversos , Poluição por Petróleo/análise , Conteúdo Gastrointestinal/química , Brasil , Poluentes Químicos da Água/toxicidade , Resíduos Sólidos/análise , Plásticos , Ingestão de Alimentos
3.
Mar Pollut Bull ; 200: 116049, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290360

RESUMO

Concerning microplastics (MPs) contamination is increasing due their negative impacts on marine food webs and their potential toxicity to wildlife and humans. In this study, we analyze the presence of MPs in the stomachs of the commercial fish species Scomber colias (Atlantic chub mackerel) in the Gulf of Cadiz (GoC). Out of the 104 analyzed stomachs, 90.4 % contained some type of MPs, with an average of 5.4 MPs per individual. Of the 1152 MPs analyzed, 91.1 % were fibers, and 8.9 % fragments type. Fourier Transformation Infrared Spectrometry analysis was performed on 152 items, revealing that 73.6 % were MPs. The most common synthetic polymers found were polyamide (64 %), polypropylene (15 %), polystyrene (12 %), polyvinyl chloride (5 %), and polyethylene (4 %). The consistent ingestion of synthetic polymers by the individuals of Atlantic chub mackerel across different zones might suggest an even distribution of MP contamination throughout the GoC.


Assuntos
Cyprinidae , Perciformes , Poluentes Químicos da Água , Humanos , Animais , Microplásticos/análise , Plásticos/análise , Conteúdo Gastrointestinal/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Peixes , Europa (Continente)
4.
Mar Pollut Bull ; 196: 115646, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832498

RESUMO

An increasing number of organisms from the polar regions are reported contaminated by plastic. Rarely a non-killing sampling method is used. In this study we wanted to assess plastic levels using stomach flushing and evaluate the method suitability for further research and monitoring. The stomach of 22 fulmars from Bjørnøya, Svalbard, were flushed with water in the field. On return to the laboratory, the regurgitated content was digested using potassium hydroxide. The extracted plastics were visually characterised and analysed with spectroscopy. Only three birds had plastics in their stomach, totaling 36 particles, most of them microplastics (< 5 mm). The plastic burdens are much lower than previously reported in Svalbard. The stomach flushing is assumed not to allow the collection of the gizzard content. This is a major limitation as most of the plastics accumulate in the fulmar's gizzard. However, the method is still useful for studies investigating plastic ingestion dynamics, allowing to sample the same individuals over time.


Assuntos
Plásticos , Poluentes Químicos da Água , Humanos , Animais , Plásticos/análise , Microplásticos/análise , Conteúdo Gastrointestinal/química , Monitoramento Ambiental/métodos , Aves , Ingestão de Alimentos , Poluentes Químicos da Água/análise
5.
Sci Total Environ ; 896: 165313, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37406705

RESUMO

The feeding habit of large-head hairtail (Trichiurus lepturus) in the northern South China Sea was investigated through isotopic and stomach content analyses. The isotopic features of the hairtail at the same body size differed among regions, with the fish in coastal waters presenting higher δ15N and δ13C values compared to those in the open sea, indicating different trophic levels (TL), food habits, and isotopic baselines. According to the partial correlation of water depth with δ15N values, the sampling stations were divided into three regions based on the depth of water: coastal (20-40 m), near coastal (60-80 m), and open sea (100-200 m) regions. In the coastal region, the hairtail from stations affected by the Pearl River plume exhibited lower δ15N and δ13C values. The stomach content analysis indicated different feeding habits of the hairtail from different regions. The hairtail in the coastal and near coastal waters fed more on fish and less on crustaceans compared to the hairtail in the open sea. The relationship between δ15N and fish size exhibited two contrary patterns. First, the δ15N values increased with increasing preanal length in the hairtail sampled from the water depth of 30-40 m in section F (in fish with preanal length < 200 mm) and those samples from the water depth of 100-200 m. This finding reflected an ontogenetic shift in diet and TL. However, the δ15N values tended to decrease with the increasing preanal length of the hairtail samples collected from the water depth of 30-40 m in section F (fish with a preanal length of ~200-300 mm). These findings suggested that under the conditions of insufficient availability of high-quality prey, the larger hairtail fed more on low-TL prey to compensate for the increase energy demand, arising due to growth, which led to the observed decrease in δ15N values.


Assuntos
Conteúdo Gastrointestinal , Perciformes , Animais , Conteúdo Gastrointestinal/química , Peixes , Isótopos de Carbono/análise , China , Água/análise
6.
Sci Total Environ ; 894: 164684, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37315594

RESUMO

Microplastics are one of the major environmental issues that need to be addressed because they are starting to impact food chains and are also affecting human populations. The size, colour, form, and abundance of microplastics in young blennies of the species Eleginops maclovinus were examined in the current study. While the stomach contents of 70 % of the studied individuals contained microplastics, 95 % of them included fibres. Individual size and the largest particle size that can be eaten, which ranges between 0.09 and 1.5 mm present no statistical correlation. The quantity of particles taken in by each individual does not change with size. The most present microfibers colours were blue and red. Sampled fibres were analysed with FT-IR and no natural fibres were detected, proving the synthetic origin of the detected particles. These findings suggest that protected coastlines create conditions that favour the encounter of microplastics increasing local wildlife exposure to microplastics, raising the danger of their ingestion with potential physiological, ecological, economical and human health consequences.


Assuntos
Perciformes , Poluentes Químicos da Água , Humanos , Animais , Microplásticos , Plásticos , Conteúdo Gastrointestinal/química , Monitoramento Ambiental , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
7.
J Fish Biol ; 102(5): 1049-1066, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36794305

RESUMO

In the northern Gulf of St. Lawrence (nGSL), redfish (Sebastes mentella and Sebastes fasciatus combined) are at record levels of abundance following the strong recruitment of three consecutive cohorts in 2011-2013 and have become by far the most abundant demersal fish in the region. Understanding redfish trophic relationships is essential for the effective management and conservation of species in the nGSL ecosystem. To date, description and quantification of redfish diet in the region have been restricted to conventional stomach content analysis (SCA). Using analysis of fatty acid (FA) profiles as complementary dietary tracers, the authors conducted multivariate analyses on 350 livers of redfish which were collected in combination with stomach contents during a bottom-trawl scientific survey in August 2017. The predator FA profiles were compared to those of eight different redfish prey types identified as dietary important with SCA. Results suggested similitude between SCA and FA results, with zooplankton prey being more related to small (<20 cm) and medium (20-30 cm) redfish (16:1n7, 20:1n?, 22:1n9 and 20:5n3) than large (≥30 cm) ones, whereas shrimp prey seemed more related to large redfish size classes (18:2n6 and 22:6n3) relative to the small and medium ones. Although the SCA offers a glimpse in the diet only based on the most recently consumed prey, analysis of FA profiles provides a mid-term view indicating pelagic zooplankton consumption on calanoid copepod and confirming high predation pressure on shrimp. This study constitutes the first attempt of combining FA with SCA to assess the diet of redfish, highlights the benefits of FA as a qualitative tool and suggests improvements for future studies.


Assuntos
Conteúdo Gastrointestinal , Perciformes , Animais , Conteúdo Gastrointestinal/química , Ecossistema , Ácidos Graxos/análise , Peixes , Dieta/veterinária
8.
Mar Pollut Bull ; 185(Pt B): 114333, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36372049

RESUMO

The northern fulmar Fulmarus glacialis ingests a larger number of (micro)plastics than many other seabirds due to its feeding habits and gut morphology. Since 2002, they are bioindicators of marine plastics in the North Sea region, and data are needed to extend the programme to other parts of their distribution areas, such as the Arctic. In this study, we provide data on ingested plastics by fulmars collected in 1997 in Kongsfjorden, Svalbard. An extraction protocol with KOH was used and for half of the birds, the gizzard and the proventricular contents were analysed separately. Ninety-one percent of the birds had ingested at least one piece of plastic with an average of 10.3 (±11.9 SD) pieces. The gizzards contained significantly more plastics than the proventriculus. Hard fragments and polyethylene were the most common characteristics. Twelve percent of the birds exceeded the EcoQO value of 0.1 g.


Assuntos
Conteúdo Gastrointestinal , Plásticos , Animais , Plásticos/análise , Conteúdo Gastrointestinal/química , Monitoramento Ambiental/métodos , Svalbard , Aves , Regiões Árticas , Polietileno/análise
9.
Mar Environ Res ; 182: 105770, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36265253

RESUMO

Assessing organic matter fluxes and species interactions in food webs is of main interest to understand the ecological functioning in bays and estuaries characterised by a wide diversity of primary producers and consumers. Demersal fish and cephalopod assemblages were studied across a network of 24 shallow subtidal stations in the bay of Saint-Brieuc for their diversity, stable isotope compositions and stomach contents. The community was composed of 21 taxa, eight species accounting for 94.4% of the total abundance. Three different assemblages were identified along bathymetric gradient and spatial patterns in fish dredging. Marine POM and SOM were the most likely bases of food webs regarding δ13C range displayed by fish and cephalopod without differences among assemblages. Amphipoda was the main prey item in stomachs leading to significant diet overlaps among fish species, with some variations in additional items. Sepia officinalis was characterised by a singular diet and very low dietary overlap with other species. Contrasted stable isotope values and niche overlaps among species were evidenced in the δ13C/δ15N space. Callionymus lyra and Buglossidium luteum, characterised by the widest isotopic niches, encompassed those of other species, except the singular 13C-depleted Spondyliosoma cantharus. Coupling taxonomic assemblages, stomach contents and stable isotope analyses help disentangling the resources uses and evidencing trophic pathways. Contrasts in fish and cephalopod demersal assemblages occurring at different depths not necessarily imply differences in the trophic resources uses in such complex shallow coastal ecosystems under anthropogenic influences.


Assuntos
Ecossistema , Perciformes , Animais , Conteúdo Gastrointestinal/química , Efeitos Antropogênicos , Cadeia Alimentar , Peixes , Isótopos de Nitrogênio/análise
10.
Mar Pollut Bull ; 184: 114096, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36113176

RESUMO

Plastic is an omnipresent pollutant in marine ecosystems and is widely documented to be ingested among seabird species. Procellariiformes are particularly vulnerable to plastic ingestion, which can cause internal damage, starvation, and occasionally mortality. In this study, 34 fledgling Fairy Prions (Pachyptila turtur) recovered during a wreck event in south-eastern Tasmania in 2022 were examined for ingested plastics and body condition (e.g., wing chord length). While many of the birds exhibited poor body condition, this was not correlated with the count or mass of ingested plastics. We hypothesise the marine heatwave event, and resulting lack of prey, contributed to bird body condition and subsequent mortality. We provide some of the first data on the size of individual plastic particles ingested by seabirds and make recommendations for future studies to report this important metric in a consistent manner that ensures data are comparable.


Assuntos
Poluentes Ambientais , Príons , Animais , Plásticos , Conteúdo Gastrointestinal/química , Ecossistema , Tasmânia , Monitoramento Ambiental/métodos , Ingestão de Alimentos , Aves , Resíduos/análise
11.
Mar Environ Res ; 179: 105676, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35803050

RESUMO

The ingestion of anthropogenic plastic debris by marine wildlife is widespread in the Mediterranean Sea. The endangered status (in the IUCN Red List) of Loggerhead turtle (Caretta caretta, Linnaeus, 1758) is a consequence of its vulnerability. In this study, macro-/meso-plastics (5-170 mm) collected from faeces of twelve loggerhead turtles rescued (live) in the Aeolian Archipelago (Southern Tyrrhenian Sea, Italy) were analyzed by size, weight, shape, color and polymer type through Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR). The defecation rate during hospitalization (7-14 days) varied among turtles (from 0.08 to 0.58). The mean number of plastic expulsions (2.7 ± 1.8 items for turtle) was higher during the 5th day of hospitalization (Kruskal-Wallis test, P = 0.01). However, the mean number of plastic-like items defecated during the common days of hospitalization did not vary among turtles (Kruskal-Wallis test, P > 0.05). All turtles were found to have ingested plastic. A total of 114 debris items were recovered from their faeces, 113 of which were identified as plastic. Their color was mostly white-transparent (64.9%) and light (19.3%). Shape was mainly fragments (52.6%), sheets (38.6%), followed by nylon, net-fragments, elastic plastic, foamed plastic and industrial granules (8.8%). Meso-plastics (5-25 mm) represented 72% of the total number of debris and were found more frequently in turtle with Curved Carapace Length (CCL) ≤ 60 cm (CCL = 30-60 cm, n = 5) than those with CCL >60 cm (CCL = 60-71 cm, n = 7). Plastic items were composed mainly of polyethylene (48.2%) and polypropylene (34.2%). Polypropylene (R2 = 0.95, P < 0.001) and polyisoprene (R2 = 0.45, P = 0.017) were more common in meso-plastics while polyethylene (R2 = 0.44, P < 0.01) in macro-plastics. Finally, high-density polyethylene, polyvinyl chloride, polyamide and polyurethane were also found in some turtles. This study reveals high spreads of plastic contamination in faeces of both turtles with CCL ≤60 cm and CCL >60 cm, particularly vulnerable to the increasing quantity of floating plastic into their foraging sites highlighting the need of further research to associate debris ingestion with turtle diet and their size.


Assuntos
Tartarugas , Poluentes da Água , Animais , Conteúdo Gastrointestinal/química , Plásticos/análise , Polietileno/análise , Polímeros/análise , Polipropilenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes da Água/análise
12.
Sci Rep ; 12(1): 10244, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715497

RESUMO

Understanding the impacts of microplastics on living organisms in aquatic habitats is one of the hottest research topics worldwide. Despite increased attention, investigating microplastics in underwater environments remains a problematic task, due to the ubiquitous occurrence of microplastic, its multiple modes of interactions with the biota, and to the diversity of the synthetic organic polymers composing microplastics in the field. Several studies on microplastics focused on marine invertebrates, but to date, the benthic sea slugs (Mollusca, Gastropoda, Heterobranchia) were not yet investigated. Sea slugs are known to live on the organisms on which they feed on or to snack while gliding over the sea floor, but also as users of exogenous molecules or materials not only for nutrition. Therefore, they may represent a potential biological model to explore new modes of transformation and/or management of plastic, so far considered to be a non-biodegradable polymer. In this study we analysed the stomachal content of Bursatella leachii, an aplysiid heterobranch living in the Mar Piccolo, a highly polluted coastal basin near Taranto, in the northern part of the Ionian Sea. Microplastics were found in the stomachs of all the six sampled specimens, and SEM/EDX analyses were carried out to characterize the plastic debris. The SEM images and EDX spectra gathered here should be regarded as a baseline reference database for future investigations on marine Heterobranchia and their interactions with microplastics.


Assuntos
Gastrópodes , Poluentes Químicos da Água , Animais , Dieta , Monitoramento Ambiental/métodos , Conteúdo Gastrointestinal/química , Microplásticos , Plásticos , Polímeros , Lanches , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
13.
J Fish Biol ; 101(3): 560-572, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35638307

RESUMO

Trophic ecology studies on predator-prey interactions reveal insights into ecological communities and help understand a species' role in the food web by contributing to improved fisheries management and conservation capabilities. Understanding the ecological role of overexploited and endangered predators is essential to deciphering how their feeding behaviour influences food web dynamics. In this study, the authors investigated the feeding behaviour of the common and IUCN-listed Near Threatened (NT) thornback ray Raja clavata, using carbon and nitrogen stable isotope and stomach content analysis (SCA). It has recently suffered an 87% decline in reported catches from the Sea of Marmara within the last decade. These results show that thornback ray mainly feeds on teleost species, except in summer, with both methods showing this species changes its diet ontogenetically by SCA. This ontogenetic diet shift was at lengths 40-50 cm by changing group preferences from Crustacea to Teleostei. MixSIAR results showed that both adult and juvenile individuals of R. clavata feed mainly on the crustaceans, but the contribution of teleosts represented by Trachurus sp. was very low (<15%). The trophic position increased total length and was higher than other batoid species in the Sea of Marmara.


Assuntos
Rajidae , Animais , Isótopos de Carbono/análise , Crustáceos , Dieta/veterinária , Peixes , Cadeia Alimentar , Conteúdo Gastrointestinal/química , Isótopos de Nitrogênio/análise , Estado Nutricional
14.
Molecules ; 27(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35164337

RESUMO

The skipjack tuna (Katsuwonus pelamis) is a mesopredator fish species with seasonal abundance in waters off Taiwan. Regional ecological and life-history information has been historically lacking for this species. In recent years, stable isotope analysis (SIA) of carbon and nitrogen has been used to assess predator feeding ecology and broader ecosystem trophic dynamics. This study evaluated comparative skipjack feeding ecology in distinct regions off Taiwan, combining traditional stomach content analysis with SIA of individuals off western (n = 43; 2020) and eastern (n = 347; 2012-2014 and n = 167; 2020) Taiwan. The stomach content analysis showed the most important prey to be ponyfish (Photopectoralis bindus) in western Taiwan and epipelagic squids (Myopsina spp.) and carangids (Decapterus macrosoma;) in eastern Taiwan from 2012 to 2014 and epipelagic carangids (Decapterus spp.) and flying fishes (Cheilopogon spp.) in eastern Taiwan in 2020, suggesting that the skipjack tuna is a generalist predator across regions. In contrast, time-integrated diet estimates from Bayesian mixing models indicated the importance of cephalopods and crustaceans as prey, potentially demonstrating more mesopelagic feeding in less productive waters during skipjack migrations outside the study regions. Skipjack off western Taiwan had a slightly higher estimated trophic position than in the waters off eastern Taiwan, potentially driven by the varying nutrient-driven pelagic food web structures. Skipjack SI values increased with body size off eastern Taiwan but not in western waters, suggesting that opportunistic predation can still result in different predator-prey size dynamics between regions.


Assuntos
Ração Animal/análise , Peixes/classificação , Conteúdo Gastrointestinal/química , Atum/fisiologia , Ração Animal/classificação , Animais , Teorema de Bayes , Decapodiformes/classificação , Cadeia Alimentar , Estado Nutricional , Comportamento Predatório , Taiwan
15.
Mar Environ Res ; 173: 105513, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34763316

RESUMO

The invasive sally lightfoot crab Percnon gibbesi (H. Milne Edwards, 1853) has spread among the coasts of the Mediterranean Sea, including the coasts of Annaba Gulf (Algeria). Investigating the trophic position of the species and looking for the seasonal variations in the diet of this alien decapod was the aim of this study. To do this, samples of P. gibbesi were collected along Annaba coasts within a year. The traditional stomach content analysis (SCA) was integrated to the stable isotope analysis (SIA) of nitrogen and carbon to provide a comprehensive evaluation of the feeding ecology of P. gibbesi, and its within-year variability. Results highlighted, for the first time, significant seasonal variation in P. gibbesi diet, improving our understanding of its trophic plasticity and potential dietary overlaps with other herbivore species. Its feeding plasticity is an asset in the successful expansion of its distribution. Relating its diet composition through the different seasons with the interactions with native herbivores will be essential to fully appreciate the impact of the spread of P. gibbesi in the Mediterranean Sea.


Assuntos
Braquiúros , Animais , Isótopos de Carbono/análise , Dieta , Ecologia , Peixes , Cadeia Alimentar , Conteúdo Gastrointestinal/química , Isótopos , Isótopos de Nitrogênio/análise , Estações do Ano
16.
Artigo em Inglês | MEDLINE | ID: mdl-34737157

RESUMO

Prominent ontogenetic changes of the gastrointestinal tract (GIT) should occur in mammals whose neonatal diet of milk differs from that of adults, and especially in herbivores (as vegetation is particularly distinct from milk), and even more so in foregut fermenters, whose forestomach only becomes functionally relevant with vegetation intake. Due to the protracted lactation in marsupials, ontogenetic differences can be particularly well investigated in this group. Here, we report body mass (BM) scaling relationships of wet GIT content mass in 28 in-pouch young (50 g to 3 kg) and 15 adult (16-70 kg) western grey kangaroos Macropus fuliginosus melanops. Apart from the small intestinal contents, in-pouch young and adults did not differ in the scaling exponents ('slope' in log-log plots) but did differ in the scaling factor ('intercept'), with an implied substantial increase in wet GIT content mass during the out-of-pouch juvenile period. In contrast to forestomach contents, caecum contents were elevated in juveniles still in the pouch, suggestive of fermentative digestion of milk and intestinal secretion residues, particularly in the caecum. The substantial increase in GIT contents (from less than 1 to 10-20% of BM) was associated mainly with the increase in forestomach contents (from 25 to 80% of total GIT contents) and a concomitant decrease in small intestine contents (from 50 to 8%), emphasizing the shifting relevance of auto-enzymatic and allo-enzymatic (microbial) digestion. There was a concomitant increase in the contents-to-tissue ratio of the fermentation chambers (forestomach and caecum), but this ratio generally did not change for the small intestine. Our study not only documents significant ontogenetic changes in digestive morpho-physiology, but also exemplifies the usefulness of intraspecific allometric analyses for quantifying these changes.


Assuntos
Conteúdo Gastrointestinal/química , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/fisiologia , Macropodidae/crescimento & desenvolvimento , Macropodidae/fisiologia , Animais , Fenômenos Fisiológicos do Sistema Digestório , Feminino , Fermentação/fisiologia , Masculino , Modelos Biológicos
17.
Environ Pollut ; 292(Pt A): 118274, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606971

RESUMO

The ingestion of plastic is becoming a major concern for various species and particularly for marine turtles across the globe. The loggerhead sea turtle (Caretta caretta) was recently chosen by the European Commission as a bio-indicator for plastic pollution within the Mediterranean basin. We further investigated which items this key species is more prone to ingest, following the standardised Marine Strategy Framework Directive protocols. Moreover, we integrated to this protocol the Fourier Transform Infrared Spectroscopy, which allowed us to determine the polymer type of each item. We analysed samples from 226 sea turtles from 2008 to 2017 in two areas of the western Mediterranean sub-region (sensu MSFD). In the Lazio area we found a frequency of occurrence of plastic ingestion of 78.33%, while in Sardinia 41.79%. The analysis of the litter categories, among all individuals, highlights a prevalence of user-sheet (Use-She; 69.13%) and user-fragment plastics (Use-Fra; 20.84%). In addition, the polymer analysis showed a dominance of polyethylene (65.98%) and polypropylene (26.23%). As a result, by looking at other works that have investigated polymer types and items sources, we are able to infer that 77.25% of the objects ingested by the C. caretta individuals are attributable to disposable daily-life objects managed in an improper way. Therefore, C. caretta apart from being an efficient bio-indicator for plastic pollution, highlighting spatial and temporal concentration differences, it could also be used to verify the effectiveness of the Single-use Plastic Directive (EU 2019/904).


Assuntos
Tartarugas , Poluentes da Água , Animais , Feminino , Conteúdo Gastrointestinal/química , Mar Mediterrâneo , Plásticos , Polímeros , Prevalência , Poluentes da Água/análise
18.
Sci Total Environ ; 810: 152264, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902420

RESUMO

Although the ingestion of plastics has been reported in a wide variety of organisms, there remains a lack of knowledge regarding the extent of spatial and temporal gradients and no consensus concerning the definition of monitor species for benthic marine environments. The present study aims at demonstrating the correlation between the presence of tangled balls of fibres and high levels of total plastic fibre ingestion in Nephrops norvegicus to assess the potential use of the prevalence of tangled balls as indicators of fibre pollution. To do so, the presence of plastics in stomach contents from several European populations of N. norvegicus is characterized in detail, including size distribution and polymer composition, and then its correlation with the prevalence of balls tested. Our results demonstrate that the prevalence of balls (>20%) is significantly correlated to higher levels of plastic ingestion, regardless of polymer composition and size distribution of ingested fibres. Plastic fibre ingestion levels across wide temporal and geographical scales are assessed using only the prevalence of balls, highlighting areas of increased fibre ingestion (e.g., the Gulf of Cadiz, N Barcelona) and areas of potentially lower fibre pollution (e.g., the Ebro Delta, the NW Iberian margin). Moreover, the relationship between the prevalence of balls and diet composition is analysed to discard a potential relationship with geographical differences in diet habits. Finally, we discuss the benefits and drawbacks of the use of the prevalence of tangled balls of fibres as an affordable, cost-effective and easy to implement indicator of fibre pollution for monitoring purposes in this species.


Assuntos
Plásticos , Poluentes Químicos da Água , Ingestão de Alimentos , Monitoramento Ambiental , Conteúdo Gastrointestinal/química , Poluentes Químicos da Água/análise
19.
Mar Pollut Bull ; 173(Pt A): 113009, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34607128

RESUMO

The pervasiveness of marine debris is now considered one of the most persistent changes in marine environments. This study reports marine debris ingested by green sea turtles Chelonia mydas and loggerhead sea turtles Caretta caretta that stranded along the eastern coast of the Sharjah Emirate in the United Arab Emirates. We observed that both green and loggerhead sea turtles frequently ingest (Frequency of Occurrence: 75.0% and 57.1% respectively) high quantities of marine debris, particularly plastics. The results suggest that green sea turtles are more likely to ingest soft items such as threads and sheets while loggerheads are more likely to ingest hard items. When considering the quantity, frequency and nature of ingested marine debris as well as the physiology of specific species and age classes, green sea turtles, particularly younger specimens, ingest the greatest amount of marine debris.


Assuntos
Tartarugas , Poluentes da Água , Animais , Ingestão de Alimentos , Conteúdo Gastrointestinal/química , Plásticos , Poluentes da Água/análise
20.
Mar Pollut Bull ; 173(Pt B): 113046, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34673429

RESUMO

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.


Assuntos
Plásticos , Spheniscidae , Animais , Brasil , Ingestão de Alimentos , Monitoramento Ambiental , Conteúdo Gastrointestinal/química , Resíduos/análise
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