The study of the cellular mechanisms of tolerance of organisms to pollution is a key issue in aquatic environmental risk assessment. Recent evidence indicates that multixenobiotic resistance (MXR) mechanisms represent a general biological defense of many marine and freshwater organisms against environmental toxicants. In this work, toxicologically relevant xenobiotic efflux transporters were studied in early life stages of zebra mussels (Dreissena polymorpha). Expression of a P-gp1 (ABCB1) transporter gene and its associated efflux activities during development were studied, using qRT-PCR and the fluorescent transporter substrates rhodamine B and calcein-AM combined with specific transporter inhibitors (chemosensitizers). Toxicity bioassays with the model P-gp1 chemotherapeutic drug vinblastine applied singly and in combination with different chemosensitizers were performed to elucidate the tolerance role of the P-gp1 efflux transporter. Results evidenced that the gene expression and associated efflux activities of ABC transporters were low or absent in eggs and increased significantly in 1-3d old trochophora and veliger larvae. Specific inhibitors of Pgp1 and/or MRP transport activities including cyclosporine A, MK571, verapamil and reversin 205 and the musk celestolide resulted in a concentration dependent inhibition of related transport activities in zebra mussel veliger larvae, with IC50 values in the lower micromolar range and similar to those reported for mammals, fish and mussels. Binary mixtures of the tested transporter inhibitors except celestolide with the anticancer drug and P-gp1 substrate vinblastine increased the toxicity of the former compound more than additively. These results indicate that MXR transporter activity is high in early life-stages of the zebra mussel and that may play an important role in the tolerance to environmental contaminants.

Birdwatchers hold substantial potential as data collectors for research, and in Brazil, the birdwatching community has been growing since the early 2000s. Currently the effects of birds on forest patch restoration in agricultural landscapes is a major focus of avian conservation ecology, but these patches are not frequently visited by birdwatchers in Brazil, hindering the collection of useful bird data. We thus developed a project, Did I see a banded bird!?, which was designed to attract birdwatching volunteers to monitor birds within a forest patch. We explored three motivating factors to attract birdwatchers: (1) we offered an unprecedented opportunity for birdwatchers to record individual birds with colored bands, a challenging activity appealing to birdwatchers' competitive nature; (2) our study area offered a new location with free, easy access and no logistical impediments; and (3) we continuously provided information on the benefits of birdwatching records for science and society to encourage participation. The project was widely announced and we had 302 applicants. However, the barriers faced throughout the project's execution, including limited researcher-volunteer interaction, low security in the patch, and the presence of few species for birdwatchers to see, reduced the motivation and participation of most applicants. Consequently, from a list of 155 highly qualified applicants who lived near the patch and were skilled in forest birding, only 10 visited the patch. Our findings provide important guidelines for researchers planning similar citizen science projects in agricultural landscapes, mainly in countries where citizen science is still not common.

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Wildlife living within urban ecosystems have to adapt or perish. Red-legged Seriema, a large terrestrial bird, are rare in urban ecosystems, however, they have been reported in a medium-sized Brazilian city. We investigated the reasons for this occurrence as well as their behavior. We assessed the distribution of Seriemas (including fledglings), free-ranging cats, and cat-feeding points provided by humans, and past records of Seriemas in the study area. We discovered that Seriemas are sharing spatial resources with cats without apparent conflicts, and intraspecific competition was important to define the spatial distribution of Seriemas. This species is able to use human-made structures to improve territory defense and opportunistic foraging. Direct and indirect human food provisioning is helping them to survive in the studied area, but is also facilitating the domestication process, which may cause future conflicts with humans and cats. Although Seriemas have inhabited the studied urban area for years, they are still adapting their behaviors for urban life, as they have not yet perceived the dangers of automotive traffic. Our study corroborates that wild species may adapt to urban areas driven by human contact, but it also acts as a trap for the adaptive process.

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The intensification of land-use changes in tropical forests during the 20th century, mainly caused by deforestation for agricultural uses, had an overwhelming influence on bird assemblages. However, how these historical anthropogenic changes have impacted the habitat use and diet of tropical birds is poorly known. Stable isotope analysis (δ 13 C and δ 15 N) can be useful in this regard since it provides information not only on the habitat and food resource use but also insights on the dietary niche of species. Here, we aimed to evaluate whether centenary anthropogenic impacts, mainly caused by changes in landscape composition, have affected the resource and habitat use and isotopic niche width of Neotropical birds in a region that comprises two biodiversity hotspots -the Atlantic Forest and Cerrado in southeastern Brazil. We found that the niche width of all bird guilds (frugivore, granivore, insectivore, nectarivore and omnivore) was largely reduced (28-70%) from the 20th century until recently. This niche width reduction was likely associated with historical anthropogenic impacts (e.g. fragmentation, forest loss and change in agricultural practices), which are responsible for the decrease in the availability of habitat and food resources. Moreover, the mean values of δ 15 N decreased over the years in all bird guilds, which might be attributed to the expansion of agricultural areas and the increase in the use of synthetic nitrogen-based fertilizers. All the analyzed species, even though some of them are diet and habitat generalists, were strongly influenced by centenary anthropogenic actions. Our results show the consequences of human-induced changes in land use on the diet and habitat use of tropical birds that persist in fragmented landscapes, which might compromise their long-term survival and provide useful information to the conservation strategies of bird assemblages in modern landscapes.

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Many studies have shown the positive and negative impacts of feeding wild birds using feeders; however, none of them considered case studies in Brazil. In 2020, social isolation measures imposed by COVID-19 boosted Brazilians’ interest in bird feeders, encouraging a group of birders to create an event (called JaneLives) to broadcast simultaneous live images of feeders across the country. Using the structure of JaneLives and relying on volunteers, we investigated which species visit Brazilian bird feeders, and discussed the effectiveness of our opportune citizen science initiative implemented during this event. Forty-eight feeders (19 urban and 29 non-urban) included in six biomes were sampled during nine JaneLives sessions (May–November 2020). The audience watched 133 species, 104 of which were visiting feeders. Non-urban feeders ( n = 94) had higher richness than urban feeders ( n = 68), but there were shared and unique species in both strata. Thraupidae, Turdidae, small, and medium birds (< 90 g) were the most common at the feeders. Owners of 23 feeders did data sampling at least once, while the other 25 feeders were sampled by 25 online birders (94.8% of their bird records were reliable). The narration that accompanied each JaneLives session enabled the audience to learn about Brazilian birds and increased environmental awareness. Audience numbers declined over the events, but the number of online birders was not affected. Ecolodges and parks that broadcasted their feeders received new clients afterwards. The events generated social interaction and pragmatic discussions about the usage of feeders, indicating that our citizen science initiative has potential for future research. Supplementary Information The online version contains supplementary material available at 10.1007/s43388-022-00094-1.