The pollution due to plastic and other anthropogenic particles has steadily increased over the last few decades, presenting a significant threat to the environment and organisms, including avian species. This research aimed to investigate the occurrence of anthropogenic pollutants in the digestive and respiratory systems of four birds of prey: Common Buzzard (Buteo buteo), Black Kite (Milvus migrans), Eurasian Sparrowhawk (Accipiter nisus), and Northern Goshawk (Accipiter gentilis). The results revealed widespread contamination in all species with microplastics (MPs) and cellulosic anthropogenic fibers (AFs), with an average of 7.9 MPs and 9.2 AFs per specimen. Every digestive system contained at least one MP, while 65 % of specimens exhibited MPs in their respiratory systems. This is the work reporting a high incidence of MPs in the respiratory system of birds, clearly indicating inhalation as a pathway for exposure to plastic pollution. The content of MPs and AFs varied significantly when comparing specimens collected from central Madrid with those recovered from other parts of the region, including rural environments, suburban areas, or less populated cities. This result aligns with the assumption that anthropogenic particles disperse from urban centers to surrounding areas. Additionally, the dominant particle shape consisted of small-sized fibers (> 98 %), primarily composed of polyester, polyethylene, acrylic materials, and cellulose fibers exhibiting indicators of industrial treatment. These findings emphasize the necessity for further research on the impact of plastic and other anthropogenic material contamination in avian species, calling for effective strategies to mitigate plastic pollution.
Nowadays, wild animals are threatened by humans, with the number of species and individuals decreasing during recent years. Wildlife rescue centers play a vital role in the conservation of wildlife populations. This study aims to describe a new release technique, the Speaker Method, to rescue and facilitate the reunion of different baby mammals that arrived at a wildlife rescue center with their mothers within their natural habitat, avoiding the need for captivity. This method is based on a recorded baby’s cry played on a speaker to make a “call effect” in the mother. The efficacy of the Speaker Method for babies’ reunion with their mothers was 45.8% in Hoffmann’s two-toed sloths (Choloepus hoffmanni) and 91.9% in brown-throated sloths (Bradypus variegatus). Among the mantled howler monkeys (Alouatta palliata), 50% of the babies could be released using this new technique. The findings suggest that the method could be helpful in the early release of young individuals, highlighting higher release outcomes in these three species compared to traditional nursery care provided by human caretakers, who face inherent difficulties in raising young animals without their mothers.
21 April 2025 in European Journal of Wildlife Research
The Eurasian otter, Lutra lutra, faced adversity in Europe in the 1950s and 1960s due to hunting, declining fish populations and the American mink invasion. Slow recovery since the 1970s led to a ‘Near Threatened’ in the IUCN Red List status, but recent pollution, fishing pressure and habitat loss caused slight population declines. Otters, known for aquatic habits, are mainly piscivorous and exhibit solitaire or social behaviours. Infanticide with parent-offspring cannibalism has been previously reported in otter species, but although cannibalism has been suggested, it has not been documented before. This study presents the first documented case of cannibalism among free-living Eurasian otters observed in northern Norway. Some authors described cannibalism as an opportunistic resource-efficient behaviour in several mammal species, offering benefits like weight gain and reduced competition, challenging the view of adverse health effects. Factors leading to otter cannibalism include ecological changes, resource competition with other species and global warming and overfishing practices contributing to increased otter competition. Further studies will be vital to answering intriguing questions about the implications of cannibalism for otter conservation.