Fishing plastics: A high occurrence of marine litter in surf-zone trammel nets of Southern Brazil.

Plastic is one of the most commonly found residues in the marine environment, which can cause several impacts. This study evaluated the interaction of marine litter with surf-zone trammel nets in Southern Brazil. Fifty fishing operations were sampled, where 4213 items were captured: 1500 discarded fish, 1384 fragments of marine litter, and 1329 utilized fishes. Plastics were the most abundant items (n = 1363), representing 98.4% of the registered marine litter, especially plastic bags (n = 1191). 94.5% of registered marine litter is considered as single-use waste. The interaction with marine litter can cause negative impacts to small-scale fisheries (e.g. economic and damage to fishing nets). We highlight the urgency in implementing actions for urban solid waste management and public policies to reduce single-use plastics and educational campaigns on the environmental theme.

A nutritional perspective on plastic ingestion in wildlife.

Although the perils of plastics to living organisms including humans have been neglected for decades, they have recently been recognized as a major environmental problem worldwide. Little progress has been made on understanding the factors that drive species' and populations' susceptibilities to the ingestion of plastic. Here, we propose using nutritional ecology as a multidisciplinary framework for bridging the gaps that link nutrition, behavior, plastics, physiology and ecology. We show that nutritional niches are tightly linked to plastic ingestion, illustrating the application of our framework in the context of nutritional niche theory, habitat-specific foraging from species to populations, and transfer patterns in food webs.

Marine debris ingestion by the South American Fur Seal from the Southwest Atlantic Ocean.

In this paper, we examined the ingestion of marine debris (MD) in South American fur seals (SAFS), Arctocephalus australis, found dead in coastal beaches of northern Argentina and southern Brazil. Seven percent of 133 SAFS analyzed presented marine debris in their stomach (n=10), with no differences between sampling countries (Brazil n=7, Argentina n=3) and sexes (female=3; male=6). However, significant differences were observed between ages classes, with MD exclusively present in stomach contents of young specimens. Plastics represents 90% of MD ingested by the SAFS, whereas regarding the source, fishery-related items (e.g. monofilament lines) were the main MD (70%), with a lesser proportion of packaging (e.g. pieces of bags). Low numbers but large size pieces of MD were found in each stomach affected. Negative effects on the individuals could not be fully evaluated. Therefore, the potential impacts of the marine debris to the SAFS deserve further elucidation.

Beak deviations in the skull of Franciscana dolphins Pontoporia blainvillei from Argentina.

The Franciscana dolphin Pontoporia blainvillei is characterized by a long rostrum, a feature that is shared with the families formerly classified as river dolphins (Pontoporiidae, Platanistidae, Iniidae, Lipotidae). Although there are occasional reports on the existence of beak deformations, very little published information exists describing this process. The object of the present study was to describe and quantify the beak anomalies of Franciscana dolphins from the coastal waters of Argentina. Of 239 skulls analyzed 12% showed beak deviations (BD), affecting the premaxillary-maxillary and dentary bones to different extents. The occurrence of BD in the dentary bone represented 58%, whereas premaxillary-maxillary BDs were observed in 14% of the studied specimens, while the complete rostrum (dentary, premaxillary and maxillary) was affected in 28% of the skulls. Dorsoventral axis BD was more frequent than lateral BD (48 and 38%, respectively), and double BD was only observed in the dentary bone. Most of the BD observed in this study could be classified as mild/moderate, and we assume that it did not affect the feeding activities of individuals; however, 2 specimens (<1%) showed a severe and complex curvature that probably did affect them. The cause of these anomalies (natural or anthropogenic origins) is unknown but may be related to important parasite loads, heavy metal and organic contaminants and plastic ingestion that could affect the coastal dolphin in different ways. A more detailed and thorough study of these cranial anomalies is necessary.

Plastic ingestion in Franciscana dolphins, Pontoporia blainvillei (Gervais and d'Orbigny, 1844), from Argentina.

Plastic debris (PD) ingestion was examined in 106 Franciscana dolphins (Pontoporia blainvillei) incidentally captured in artisanal fisheries of the northern coast of Argentina. Twenty-eight percent of the dolphins presented PD in their stomach, but no ulcerations or obstructions were recorded in the digestive tracts. PD ingestion was more frequent in estuarine (34.6%) than in marine (19.2%) environments, but the type of debris was similar. Packaging debris (cellophane, bags, and bands) was found in 64.3% of the dolphins, with a lesser proportion (35.7%) ingesting fishery gear fragments (monofilament lines, ropes, and nets) or of unknown sources (25.0%). PD ingestion correlated with ontogenetic changes in feeding regimes, reaching maximum values in recently weaned dolphins. Because a simultaneous increase in gillnet entanglement and the bioaccumulation of heavy metals take place at this stage, the first months after trophic independence should be considered as a key phase for the conservation of Franciscana dolphin stocks in northern Argentina.