Dependence of broad-scale geographical variation in fleshy-fruited plant species richness on disperser bird species richness

Many North American grassland songbirds are experiencing significant population declines, partly because of land-use practices associated with agricultural activity. The aim of this study was to compare the habitat correlates of songbirds breeding in native mixed-grass prairie with patterns found in introduced vegetation dominated by crested wheat grass (Agropyron pectiniforme). We assessed plant species composition, habitat structure, and bird species diversity over 2 years to document species- and community-level trends in southwestern Saskatchewan, Canada. In addition to having higher plant species richness and diversity, native vegetation consisted of significantly more grass and sedge cover, less bare ground, deeper litter, and higher density within 10 cm of the ground than introduced vegetation. Bird species richness and diversity and the abundance of Baird's Sparrows (Ammodramus bairdii) and Savannah Sparrows (Passerculus sandwichensis) increased significantly along a multivariate gradient from open to more sheltered habitat, regardless of vegetation type. Sprague's Pipits (Anthus spragueii) showed a curvilinear increase along the same gradient, occurring in high numbers where habitats offered an intermediate level of cover. Our findings suggest that species richness and diversity within songbird communities and the abundance of some species may be reduced where conversion to crested wheat grass results in more open habitat.

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Bird species richness and abundance in riparian vegetation invaded by exotic Reynoutria spp.

Biologia ◽

10.2478/s11756-013-0296-x ◽

2014 ◽

Vol 69 (2) ◽

Cited By ~ 11

Author(s):

Lenka Hajzlerová ◽

Jiří Reif

Keyword(s):

Species Richness ◽

Plant Species ◽

Riparian Vegetation ◽

Bird Species ◽

Plant Invasions ◽

Alien Plant ◽

Bird Species Richness ◽

River Bank ◽

Management Actions ◽

Acrocephalus Palustris

AbstractImpacts of invasive alien plant species are threatening biodiversity worldwide and thus it is important to assess their effects on particular groups of organisms. However, such impacts were studied mostly in case of plant or invertebrate communities and our understanding the response of vertebrate species to plant invasions remains incomplete. To improve our knowledge in this respect, we studied bird communities in riparian vegetation along the rivers with different levels of Reynoutria spp. invasion in the Czech Republic. These findings will be interesting for basic ecology enhancing our knowledge of consequences of plant invasions, as well as for conservation practice. We surveyed understory bird species in 26 vegetation blocks along parts of three rivers running from the Beskydy Mountains in spring 2011. We used principal component analysis to assess vegetation structure of particular blocks and the first axis ordinated the blocks according to the degree of invasion by Reynoutria spp. Using generalized linear mixed-effects models we found that counts of Motacilla cinerea, Cinclus cinclus and Sylvia borin, as well as the total bird species richness, significantly decreased with increasing degree of Reynoutria spp. invasion, while Acrocephalus palustris showed the opposite pattern. These results suggest that Reynoutria spp. impacts negatively on the species strictly bond with river banks and habitats specialists, whereas habitat generalist species like Sylvia atricapilla were not affected. Preference of Acrocephalus palustris for Reynoutria spp. corroborates affinity of this species to large invasive herbs observed also in other studies. Our study showed that Reynoutria spp. invasion can reduce species richness of understory birds in riparian communities. Although the distribution of this plant species is still quite limited in central Europe, our results suggest that its more widespread occurrence could potentially threat some river bank bird species. Therefore, we urge for development of management actions that will act counter the Reynoutria spp. invasion.

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Accounting for geographical variation in species-area relationships improves the prediction of plant species richness at the global scale

Journal of Biogeography ◽

10.1111/jbi.12213 ◽

2013 ◽

Vol 41 (2) ◽

pp. 261-273 ◽

Cited By ~ 27

Author(s):

Katharina Gerstner ◽

Carsten F. Dormann ◽

Tomáš Václavík ◽

Holger Kreft ◽

Ralf Seppelt

Keyword(s):

Species Richness ◽

Plant Species ◽

Geographical Variation ◽

Plant Species Richness ◽

Global Scale ◽

Species Area

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Functional evenness of bird communities varies along the elevational gradient in Europe: Conservation implications

10.32942/osf.io/sx9n8 ◽

2019 ◽

Author(s):

Federico Morelli ◽

Yanina

Keyword(s):

Species Richness ◽

Elevation Gradient ◽

Bird Species ◽

Elevational Gradient ◽

Negative Association ◽

Bird Communities ◽

Breeding Bird ◽

Bird Species Richness ◽

Large Spatial Scale ◽

Functional Evenness

ContextThe negative association between elevation and species richness is a well-recognized pattern in macro-ecology. ObjectivesThe aim of this study was to investigate changes in functional evenness of breeding bird communities along an elevation gradient in Europe. MethodsUsing the bird data from the EBCC Atlas of European Breeding Birds we estimated an index of functional evenness which can be assumed as a measure of the potential resilience of communities.ResultsOur findings confirm the existence of a negative association between elevation and bird species richness in all European eco regions. However, we also explored a novel aspect of this relationship, important for conservation: Our findings provide evidence at large spatial scale of a negative association between the functional evenness (potential community resilience) and elevation, independent of the eco region. We also found that the Natura2000 protected areas covers the territory most in need of protection, those characterized by bird communities with low potential resilience, in hilly and mountainous areas.ConclusionsThese results draw attention to European areas occupied by bird communities characterized by a potential lower capacity to respond to strong ecological changes, and, therefore, potentially more exposed to risks for conservation.

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