RESUMO
Studying social-behavior and species associations in ecological communities is challenging because it is difficult to observe the interactions in the field. Animal behavior is especially difficult to observe when selection of habitat and activities are linked to energy costs of long-distance movement. Migrating communities tend to be resource specific and prefer environments that offer more suitability for coexisting in a shared space and time. Given the recent advances in digital technologies, digital video recording systems are gaining popularity in wildlife research and management. We used digital video recording cameras to study social interactions and species-habitat linkages for wintering waterbirds communities in shared habitats. Examining over 8,640 hr of video footages, we built tetrapartite social-behavioral association network of wintering waterbirds over habitat (n = 5) selection events in sites with distinct management regimes. We analyzed these networks to identify hub species and species role in activity persistence, and to explore the effects of hydrological regime on these network characteristics. Although the differences in network attributes were not significant at treatment level (p = .297) in terms of network composition and keystone species composition, our results indicated that network attributes were significantly different (p = .000, r 2 = .278) at habitat level. There were evidences suggesting that the habitat quality was better at the managed sites, where the formed networks had more species, more network nodes and edges, higher edge density, and stronger intra- and inter-species interactions. In addition, we also calculated the species interaction preference scores (SIPS) and behavioral interaction preference scores (BIPS) of each network. The results showed that species synchronize activities in shared space for temporal niche partitioning in order to avoid or minimize any potential competition for shared space. Our social network analysis (SNA) approach is likely to provide a practical use for ecosystem management and biodiversity conservation.
RESUMO
From October 2010 to October 2012 (total 126 days), we used the line transect method combined with interviews applied during seven individual surveys to explore the bird resources of Qomolangma National Nature Reserve (QNNR). Based on the historical records and the present results, a total of 390 bird species belonging to 62 families and 18 orders, had been confirmed. Our results indicated that QNNR plays a vital and unique role in bird species preservation and scientific study, especially for endemic and endangered species. Species richness of both the Palearctic and Oriental realms were different, there was no overall significant difference (164 and 178, respectively). Species differences between the northern and southern slope of QNNR were especially remarkable. The northern slope was characterized with enriched endemic plateau species over small total number of bird species the southern flank held an abundance of bird species with complex composition. Moreover, on the southern slope, the peak of breeding birds richness occurred at 2,500~3,100 m a.s.l., supporting the mid-domain effect hypothesis. Meanwhile, as elevation increased, the richness of Oriental species decreased while that of Palearctic species increased. The percentages of Oriental and Palearctic species were similar at 3,100~4,000 m a.s.l.. Accordingly, we estimated that the boundary of Oriental realm and Palearctic realm was at 3,100~4,000 m a.s.l., and the species invasion from Palearctic to Oriental realm was more obvious. Perhaps most significantly, the specific distribution species along the vertical gradients also indicated their corresponding adaptation strategies.