Native ecosystems are continuously being transformed mostly into agricultural lands. Simultaneously, a large proportion of fields are abandoned after some years of use. Without any intervention, altered landscapes usually show a slow reversion to native ecosystems, or to novel ecosystems. One of the main barriers to vegetation regeneration is poor propagule supply. Many restoration programs have already implemented the use of artificial perches in order to increase seed availability in open areas where bird dispersal is limited by the lack of trees. To evaluate the effectiveness of this practice, we performed a series of meta-analyses comparing the use of artificial perches versus control sites without perches. We found that setting-up artificial perches increases the abundance and richness of seeds that arrive in altered areas surrounding native ecosystems. Moreover, density of seedlings is also higher in open areas with artificial perches than in control sites without perches. Taken together, our results support the use of artificial perches to overcome the problem of poor seed availability in degraded fields, promoting and/or accelerating the restoration of vegetation in concordance with the surrounding landscape.

The breeding avifauna of 25 woodland fragments (0.85–280 ha) was studied between 1996 and 2004 in Córdoba, Argentina. A distinctive feature of the avifauna of the fragments studied is the low area requirement of most of the species. Of the 54 woodland species recorded, 32 (59.3%) require c. 1 ha and 43 (79.6%) needed no more than 3 ha. Also noticeable is the relatively high number of individuals of most of the species. Both characteristics suggest a good tolerance to fragmentation. However, nine species (16.7%), the area‐sensitive species, need fragments of 80 ha or larger. Moreover, eight resident species have apparently become extinct in the fragments that were studied, including the five large species that originally inhabited the area. Proportional odds and log linear models were fitted to relate the minimum area requirements of these species to various ecological characteristics (body size, diet, habitat use, migratory status, and nest type). Closed nesters, resident, woodland exterior, and medium‐size species were the groups requiring larger areas. No apparent pattern was observed between area requirements and diet. A recent law prohibits woodland removal, which is a positive step towards the conservation of the fragments. The results suggest that as long as the present amount of woodland is maintained, the situation of the avifauna of the fragments is relatively secure, at least in the short term.

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In central Argentina, Serrano forest has a long history of fire disturbance; however, the impact of fire on avifauna remains unknown. We compared the avian-habitat relationships in forest patches with low, moderate, and high fire regimes using a community-level (species richness, abundance, ordination and guilds) and species-level (indicator species analysis) approach. In patches under each fire condition, we recorded bird community composition, richness and abundance, and different vegetation structure variables. The site under high-severity fire regime was structurally poor and had been converted from original forest to dense grassland. There, diversity of bird community was low, retaining approximately 30 % of the species present in the least impacted site. Avian assemblage was dominated by generalist and open area birds. Guilds were underrepresented, showing an important reduction of foliage granivorous, nectarivorous, omnivores, and foliage and bark insectivorous, and absence of flycatchers. Moreover, low abundance of forest understory, midstory, and canopy species and of birds belonging to open and closed nesting guilds was detected. By contrast, under low and moderate-severity fire regimes highest bird diversity as well as highest representativeness of most guilds was observed. Forest bird species were strongly associated with low fire disturbance, whereas moderate fire disturbance was characterized by the presence of forest and generalist species. Given the critical conservation status of Serrano forest in Co ´rdoba, Argentina, habitat restoration and protection of forest relicts could be suitable measures to promote avifauna preservation.