Promoting Bird Functional Diversity on Landscapes with a Matrix of Planted Eucalyptus spp. in the Atlantic Forest.

Promoting the diversity of biological communities in areas of agricultural production is a very current debate since protected areas may not be sufficient to ensure biodiversity conservation. Among the biological communities affected by the production areas are birds, which show rapid responses to changes in the landscape. Here we seek to understand how landscape planning, concerning its composition and configuration, in areas with a matrix of planted Eucalyptus spp. forests influences the functional diversity of bird assemblages in the Atlantic Forest. Our results show that the spatial distribution design of planted forests in terms of age, land cover and clone types have effects on bird diversity with regard to functional divergence, functional evenness and species richness. These results reinforce the importance of good management for the maintenance of bird diversity. We found that bird functional diversity in planted forest matrices increased with the proximity index, proportion of native vegetation and age importance value, and is negatively influenced by edge density and proportion of forest plantation. For bird conservation, it is thus better to associate Eucalyptus spp. with other cover types in the landscape. These results corroborate that, to increase bird functional diversity, it is possible to associate conservation and production in the same landscape. Mosaic landscapes have great potential to contribute to the conservation of bird biodiversity outside protected areas. However, decisions regarding the management of planted forests and planning of improved areas intended for conservation seem to be decisive to ensure the maintenance of bird biodiversity.

Which birds are Brazilians seeing on urban and non‑urban feeders? An analysis based on a collective online birding

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.

Human-modified landscapes narrow the isotopic niche of neotropical birds.

Deforestation and habitat loss resulting from land use changes are some of the utmost anthropogenic impacts that threaten tropical birds in human-modified landscapes (HMLs). The degree of these impacts on birds' diet, habitat use, and ecological niche can be measured by isotopic analysis. We investigated whether the isotopic niche width, food resources, and habitat use of bird trophic guilds differed between HMLs and natural landscapes (NLs) using stable carbon (δ13C) and nitrogen isotopes (δ15N). We analyzed feathers of 851 bird individuals from 28 landscapes in the Brazilian Atlantic Forest. We classified landscapes into two groups according to the percentage of forest cover (HMLs ≤ 30%; NLs ≥ 47%), and compared the isotopic niche width and mean values of δ13C and δ15N for each guild between landscape types. The niches of frugivores, insectivores, nectarivores, and omnivores were narrower in HMLs, whereas granivores showed the opposite pattern. In HMLs, nectarivores showed a reduction of 44% in niche width, while granivores presented an expansion of 26%. Individuals in HMLs consumed more resources from agricultural areas (C4 plants), but almost all guilds showed a preference for forest resources (C3 plants) in both landscape types, except granivores. Degraded and fragmented landscapes typically present a lower availability of habitat and food resources for many species, which was reflected by the reduction in niche width of birds in HMLs. Therefore, to protect the diversity of guilds in HMLs, landscape management strategies that offer birds more diverse habitats must be implemented in tropical regions.