Roadsides are key habitats for birds in the Argentine Pampas: conservation and management implications

Summary Unexploited public areas such as roadsides could provide habitat to help preserve biodiversity in South America, as in other regions. Our objective was to determine the importance of the roadsides of the Argentine Pampas for native birds and to suggest management strategies. We surveyed birds inhabiting roadsides in all seasons and determined whether roadsides were used as habitat. We recorded a total of 95 species on roadsides, which represents 55% of those species described from the area. Species included specialists of grassland, wetland and woodland, 4 vulnerable species and 19 declining species. Bird richness decreased in winter, as well as grassland specialists’ abundances. Most individuals used roadsides for foraging and performing reproduction-related behaviours, mainly on native trees; these and tall grass were the main substrates. We conclude that many species of birds use the habitat provided by roadsides, and we recommend management strategies such as favouring seed availability in winter, restoring trees and tall grass and increasing vegetation diversity to maximize roadside conservation value.

Mesoscale bird distribution pattern in montane phytophysiognomies along an ecotone between two hotspots

Brazil has a high diversity of birds and presents the largest number of threatened bird species in the neotropical region. Even so, there are gaps in the bird knowledge, especially in ecotonal montane regions. Given this panorama, this study aimed to analyse the bird community distribution (richness, composition, and beta diversity between phytophysiognomies) of an ecotonal montane landscape of southeastern Brazil, with the purpose of detecting substitution patterns of bird species on a meso-scale. Using bird data performed during the years 1998 to 2015 in 46 sampling points, we found high bird richness in montane phytophysiognomies along an ecotone between Cerrado and Atlantic Forest hotspots. The composition present species of both domains, with high turnover component. We highlight the field environments and candeais are considered homogeneous and threathened, which would directly affect birds. The present study contributes to future conservation strategies, as it demonstrates ecotonal regions as transition zones and reinforces the need to consider as particular ecological units. These ecotonal regions are key locations for understanding ecological patterns in response to environmental changes or phytophysiognomies. Knowing how partitioning of the composition occurs within an environmental mosaic is essential to understand the limits and distributions of the species and conserve them.

Responses of functional traits in cavity-nesting birds to logging in subtropical and temperate forests of the Americas

Logging causes changes in habitat structure, which can potentially lead to variations in taxonomic and functional richness of biodiversity. Studies on how functional traits in birds are affected by logging operations can provide an important element for the understanding of ecosystem processes. In this paper, we examined how logging in subtropical Andean forests influenced taxonomic and functional diversity of cavity-nesting birds. We used these results to compare how logging affected ecosystem functions in temperate and subtropical forests of the Americas. We used point-counts to examine the effects of logging on taxonomic and functional traits in avian communities (Functional Richness, Functional evenness, Functional Divergence, and Community-weighted mean). We found that logging changed bird richness and abundance, although it had no effect on the functional response to the measured traits. The comparison of our results with those of temperate forests of Canada and Chile reveals differences in the functional richness of birds in these habitats, with a lower impact of logging on functional traits. We highlight the importance of including functional traits in the analyses, since the reduction in the species richness and abundance may not be translated into functional changes within the ecosystem.

Breeding birds of ‘Nomentum’ nature reserve (central Italy): a forest remnant landscape surrounded by an agro-urbanized matrix

We carried out a standardized breeding bird atlas of “Nomentum” nature reserve (central Italy), located in a fragmented hilly forest near a large urbanized area (Rome). In order to obtain data about local composition, occurrence, distribution and richness, we correlated data with environmental heterogeneity and vegetation structure variables. We recorded 58 species in 48 500x500 m-wide atlas units, with Parus major, Corvus cornix, Turdus merula, Sylvia atricapilla, Sylvia melanocephala, as the most occurring in frequency (> 80%). Although synanthropic species represent only slightly more than 20% in number and urban environments are relatively reduced in size, these species show a higher mean occurrence when compared to mosaic species, despite the fact that these last are higher in species number and mosaic habitats are widely diffused. Local urbanization may disrupt communities, facilitating opportunistic species linked to these environments (i.e. synantropic) and inducing a decline in mosaic species. Moreover, the homogenization induced by anthropization could, at least partially, explain the lack of correlation between habitat diversity and species richness, at local scale. Finally, tree density and diameter do not affect total bird richness at this spatial grain/scale. In this regard, further analyses could test for possible correlations between habitat variables and single ecological guilds.

Losses and gains of fallows drive farmland bird populations over three funding periods of the EU Common Agricultural Policy

Fallow land provides habitat for threatened and declining farmland biodiversity. Policy change under the EU's Common Agricultural Policy (CAP) has been driving the area of fallows over the past decades and influenced trends in farmland biodiversity. We analyzed the impact of changes in fallow area across Germany on species richness and abundance of farmland birds over three CAP funding periods. We examined whether responses to fallow land area were modulated by species habitat preferences and landscape complexity. We combined spatial data on fallow land area from three agricultural censuses in Germany (2007, 2010 and 2016) with country-wide, annual monitoring data on farmland birds. Farmland bird species richness and the abundance of edge- and field-breeders responded positively to increases in fallows. The effect of fallows on bird richness was strongest at intermediate levels of landscape complexity. There was support for an increasing effect strength of fallow land area on field-breeders' abundance with increasing landscape complexity. We conclude that the loss of fallows in the period 2007 to 2016 resulted in strong declines of farmland birds. We predict that a future increase of the proportion of fallow land to 4%, as envisaged in the post-2020 CAP for Germany, will result in an average increase of 7% in farmland bird species richness and of 11% in average farmland bird abundance compared to 2016, but will depend on species-specific habitat preferences. Increasing the proportion of fallow land will be a key lever to stabilize and revert negative farmland bird population trends. An increase of fallow area in all but the least complex landscapes will boost farmland bird richness and abundance of field breeders. Increasing the proportion of fallow land to 4% is projected to, on average, bring farmland bird richness and abundance back to the levels observed in 2007 acknowledging that farmland bird populations were already severely depleted in 2007. A more ambitious expansion of fallow land towards 10%, such as in the context of the EU Biodiversity Strategy for 2030, should be targeted towards areas that experienced the strongest loss of fallows and towards landscapes with intermediate structural complexity.

The Potential Role of Drove Roads as Connecting Corridors for Birds between Natura 2000 Sites

Ecological connectivity among protected Natura 2000 sites is a priority for conservation in Europe due to the increasing pressure on biodiversity from human activities and climate change. Drove roads, the traditional paths used to move livestock through the territory, have been proposed as potential ecological corridors due to their large extent, continuous nature and centennial protection from ploughing and urbanization, which allows the persistence of some tree cover and natural habitats in them. Bird communities were sampled during the reproductive season along 19 drove road transects in agrarian landscapes between Natura 2000 sites, all of them around the conurbation of Madrid (Madrid Region, Spain). Bird community nestedness was assessed by NODF computation followed by significance estimation by aleatorization, and factors explaining species richness and bird abundance were analyzed through General Linear Models fitted with environmental variables measured on official vegetation maps and orthophotos. Bird communities in drove roads were significantly nested, showing high predictability in the order of species loss from better preserved sites to those under stronger environmental pressures. Accordingly, Poisson regression showed bird richness to decrease strongly with distance from the closest Natura 2000 site and to increase with forest cover at the landscape and at the drove road scales. Bird abundance increased strongly with distance from urban areas and motorways, and it was slightly higher in areas with more forest cover and in transects with less bare ground. These results, and the higher relevance detected for landscape scale variables (500 m around transects) than for those at the drove road (50 m) scale, show that (i) they can only play a secondary role as habitat for nesting birds but (ii) they may add to the Green Infrastructure strategy as facilitators or stepping stones for bird communities if the surrounding landscape is favorable for them.

Biodiversity of Birds in Urban Green Space for Support Ecotourism activities in Valaya Alongkorn Rajabhat University Thailand

Bird watching is one of the attractive ecotourism activities for travelers and nature enthusiasts, which rapidly growing in Thailand. This study aims to: (1) explore bird diversity in various green spaces in ValayaAlongkorn Rajabhat University (VRU); and (2) examine which bird species dominates the study areas. Bird data were collected using point count techniques in two sessions; early morning, and late afternoon, at VRU from May 2020 to April 2021. Frequency of occurrence value (FQ) was analyzed for classifying status groups of birds in the VRU. Order Passeriformes was numerically the dominant order in our study area, with 22 species (47.7% of total represented species), while the other bird orders were the least dominant, represented by 1 to 5 species in range. A total of 47 species of birds belonging to 29 Families and 12 Orders were recorded. During this study, significantly, the highest bird richness was recorded in agriculture areas (35 ± 2.3 SD), followed by the species from recreation areas (27 ± 1.8 SD) and natural wetland (17 ± 1.7 SD) (P>0.05). Five migrant bird species and 35 resident species were observed, and 10 bird species were recorded in both the seasonal status as migrant and resident species. Most of the bird species are listed as of least concern, while only one species, Mycteria leucocephala, are listed as near-threatened. Nine bird species are classified as common species in the VRU with > 80 % of frequency of occurrence. The pattern of bird diversity in the VRU in general follows the natural condition of green area space in the VRU. Typical characteristics of birds, their habitat and appearing period can develop bird-watching objects, which become interesting attractions for travelers and nature enthusiasts, promoting ecotourism development and efforts to conserve bird diversity.