Higher Bird Species Richness Research Articles

Species Diversity and Feeding Guilds of Birds in Paya Indah Wetland Reserve, Peninsular Malaysia

The objective of this study was to examine the bird species diversity and feeding guilds in Paya Indah Wetland Reserve, Peninsular, Malaysia. Distance sampling-point count method was used to survey the bird species. A total of 13872 birds belonging to 100 species and 38 families were recorded. The results show that Treron vernans (12.42%), Pycnonotus goiavier (12.13%), Geopelia striata (7.58%), Porphyrio porphyrio (6.87%) and Streptopelia chinensis (6.33%) were the most dominant species in the area. The Ardeidae was the most dominant family with nine species and sixteen families were rarest only with one species each. The highest bird diversity was observed in Marsh swamp (Shannon’s N1 = 27.16), while the lowest was in Patchy shrubland (Shannon’s N1 = 22.51). The highest bird species richness was observed in Marsh swamp (Margalef’s R1 = 9.52), while the lowest was observed in open water bodies (Margalef’s R1 = 7.35). The evenness of individuals among the species was higher in Marsh swamps (Pielou J = 0.71) and lower in Patchy shrubland (Pielou J = 0.67). Analysis of variance and Tukey (HSD) tests showed that bird species among habitats is significantly different (F4, 495 = 8.82 p<0.0001). Feeding guilds indicated that insectivore was the most dominant group (37%), while Carnivore/Insectivore and Granivore were the least dominant groups (3% each) in all five habitats. This study clearly indicated that Paya Indah Wetland Reserve is highly important in providing food resources, shelter, nesting and roosting sites for wide range of bird species.

Landscape and patch-level factors influence bird communities in an urbanized tropical island

As human population continues to increase and intensification of human land use escalates, it is important to address the role of urban forest patches in supporting bird communities. We related bird species richness and community assemblage to landscape- and patch- level factors in 40 forest patches in the densely populated metropolitan area of San Juan, Puerto Rico. In total, 54 bird species were observed including 26 resident, 10 endemic, 12 migratory, and 6 introduced species. Patch size, level of urbanization in the surrounding matrix, and vertical heterogeneity of forest patches were the most important variables in explaining species richness. Patch size had the highest predictive power in explaining species richness for all groups except migrants, which were best predicted by patch-level factors (vegetation heterogeneity). The degree of matrix urbanization was correlated negatively with endemic species richness, but positively with introduced species. Endemic species were particularly sensitive to landscape factors (patch size, matrix urbanization, and canopy texture). Introduced species richness was not dependent on any patch-level factors. Eight species were relatively unaffected by urbanization, whereas two species were only found in large forest patches, and two species were sensitive to urban development. Seven species demonstrated a preference for small patches. Recommendations for land managers and conservation agencies to maintain a high bird species richness and diversity include: (1) preserve both large and small forest patches, (2) limit urban development near forest patches, (3) manage forest patch structure to maintain vertical heterogeneity, and (4) maintain forest patches with different vegetation types.

Understanding the Relationship Between Environmental Energy Availability and Bird Species Richness in Kenya Using Remote Sensing and Ancillary Data

The energy hypothesis predicts that, in regions of roughly equal area, energy flux per unit of area should be the prime determinant of species richness. In the case of plants, primary production represents realized energy capture. Poten- tial evapotranspiration is a measure of community energy use and it is related to terrestrial primary productivity. The best correlate of the latter on regional scale is the Advanced Very High Resolution Radiometer (AVHRR) derived Normalized Difference Vegetation Index (NDVI). I examined the relationship between bird species richness and measures of available environmental energy (interannual maximum average NDVI and mean annual potential evapotranspiration) at a quarter degree scale (55 x 55 km). Statistical analyses revealed higher interannual maximum average NDVI results in higher bird species richness, whereas mean annual potential evapotranspiration correlated negatively with species richness. Under- standing these relationships can help in estimating changes in bird species richness in response to global climatic change.

The white-backed woodpecker: umbrella species for forest conservation planning?

In northern Europe, a long history of land use has led to profound changes within forest ecosystems. The white-backed woodpecker (Dendrocopos leucotos) is one of several specialised forest species whose populations have declined. Conservation management directed at this species’ habitat has made it a de facto umbrella species for conservation of the biodiversity associated with forests rich in deciduous trees and dead wood. We assessed empirically the value of the white-backed woodpecker as an indicator and umbrella species in central Sweden. Occurrence of the woodpecker in breeding bird atlas squares (5 × 5 km2) indicated high species richness of forest birds, particularly species of special conservation concern, which included on average 13% more species in squares with than without the woodpecker. The number of red-listed cryptogam species expected to benefit from conservation actions directed at white-backed woodpecker habitats was higher in squares where the woodpecker bred compared to where is was absent. However, no such pattern was found for red-listed beetles, a group with very few records in the studied squares. White-backed woodpecker occurrence was positively associated with the current area of deciduous and mixed forest of high conservation value. Considering its indicator value, its specialised habitat requirements and its potential as a communication tool, using the white-backed woodpecker as an umbrella species may provide a coarse filter for the conservation of several other deciduous forest species. However, focusing solely on white-backed woodpecker habitat may not provide for the conservation of all such species, which stresses the need for a suite of complementary planning approaches.

Top predators as indicators for species richness? Prey species are just as useful

Summary The use of surrogates to identify protected areas is a common practice in conservation biology. The use of top predators as surrogates has been criticized but recently a strong positive relationship was found between the presence of top predators and species diversity of several taxa. As mentioned by the authors, these striking results need to be assessed on a larger scale. We used data from the Swiss Biodiversity Monitoring Programme and the Swiss breeding bird survey to analyse the use of raptor species as a surrogate for plant, butterfly and bird species richness. For each raptor species, we compared species richness in sites where a raptor species was recorded and compared these sites with the remaining sites in which the raptor species was not recorded. For comparison we conducted the same analyses using tits Parus spp. Tits are common prey species of some raptor species and were the most species‐rich generalist genus in our data. We found little justification for a focus on top predators when identifying conservation areas. For bird and plant species richness, raptors were reasonable surrogates for high species richness but no raptor species predicted sites with above‐average butterfly species richness. The presence of tit species performed equally as well as the presence of raptor species to predict sites with high species richness of birds and plants, and performed even better for predicting high butterfly species richness. Synthesis and applications. Conservation planners using indicator species should be aware that relationships among higher taxa are complex and depend on the species group and the scale of analysis. As shown with the case of raptors, the usefulness of a biodiversity indicator can vary between adjacent areas even if the same species groups are analysed. We recommend the use of more than one indicator species from different taxonomic groups when identifying areas of high biodiversity.

Avian diversity in a Kenyan agroecosystem: effects of habitat structure and proximity to forest

Tropical agroecosystems cover an increasingly large proportion of the Earth’s terrestrial surface. Yet, relatively little is known about the factors that influence their avifauna, especially in areas of high human population density. The potential of tropical farmland for sustaining bird biodiversity, including forest birds, can be influenced by habitat structure and the distance from the nearest forest. We investigated the effect of these two factors on the bird community in the farmland near Kakamega Forest, Kenya. Using point counts, we assessed the number of bird species and individuals on 56 study plots in distances up to about 2,100 m from the forest. We observed a total of 96 bird species in the farmland, 22 of which were forest, 58 shrub-land, and 16 open-country species. High vertical vegetation heterogeneity and a large number of woody plant individuals were related to high species richness of forest and shrub-land birds, whereas open-country birds avoided such areas. The species richness and total number of forest birds declined with increasing distance to the forest. A comparison with the bird community within Kakamega Forest indicated that only a fraction of the forest species could be sustained in the farmland. This suggests that agroecosystems with a diverse habitat structure can support a high diversity of birds, but have only a limited capacity to compensate for forest loss.

Comparisons of the alpine bird communities across habitats and between autumn and winter in the mid‐Yalong Zangbo River valley, Tibet

The extreme alpine environment around the mid‐Yalong Zangbo River on the Tibetan plateau supports a unique avifauna. To understand the structure and habitat selection of this poorly known bird assemblage, we quantified abundance of the birds in four representative types of vegetation and a human settlement inside a shrub‐covered alpine valley (29°27′N, 91°40′E, 4000–5200 m a.s.l.) in the Lhasa mountains, Tibet, from September 2004 to January 2005. A total of 40 species of birds was recorded, six of which were summer breeders, one vagrant autumn migrant, 29 permanent residents, and four local wintering migrants. Latitudinally migrating taxa were absent. Of the 33 wintering species, 70% were alpine specialists. Patterns of distribution of species and individuals differed across habitats. The highest bird species richness was found in Rose–Barberry shrub where vegetation was most complex, and fruiting and seeding plants abundant. From autumn to winter, birds tended to aggregate in the human settlement for foods supplemented by local Buddhists; as a consequence this habitat contained the highest individual density. In terms of trophic guilds, plant‐eating birds were predominant in composition (65.8–75.8%) and numerically abundant (89.8–96.7%) in all the habitats. We concluded that vegetation diversity and food supply significantly influence species composition and individual abundance of the alpine bird community. For long‐term survival of the unique bird assemblage, we argue for protection of the shrub vegetation as it is difficult to regenerate in the harsh high‐altitude conditions.

Top predators: hot or not? A call for systematic assessment of biodiversity surrogates

Summary Sergio et al. (2006) argue that top predators are justified conservation surrogates based on a case study where raptor presence is associated with high species richness of birds, butterflies and trees. We question the methodology as well as the applicability of their results, and clarify differences between surrogates for biodiversity hotspots and surrogates for complementarity. We show that the results from Sergio et al. related to richness hotspots are not fully reliable and that the ability of top predators to identify complementary areas is not demonstrated. Given that complementarity‐based surrogate studies have produced mixed results for a variety of reasons, we clarify some methodological misunderstandings while encouraging further testing of functional groups as biodiversity surrogates. Synthesis and applications. We call for caution in making generalizations, and emphasize that case studies on the use of surrogates should be conducted in a systematic manner. This will facilitate robust assessment across studies regarding the usefulness of particular species groups as biodiversity surrogates.

Birds and fish as bioindicators of tourist disturbance in springs in semi-arid regions in Mexico: a basis for management

Tourist disturbance in semi–arid springs was analysed; birds and fish were selected as bioindicators. Media Luna spring is the biggest and most spatially complex system in the region, with the highest biodiversity levels and tourist use. Areas with the highest bird species richness and abundances showed highest structural heterogeneity and least direct human impact. No differences in species richness of fish were observed between sectors and the most abundant species were found in the sectors least perturbed by human activity. Factors that explained the bird distribution were the species´ tolerance to the effects of direct tourism (noise and direct presence of people) and habitat quality, mainly riparian vegetation. Aquatic vegetation condition was very important for fish. Six bird species and two fish species were relevant as indicators of the habitat quality related to human impact. Anthropic disturbance such as tree plantation favoured some bird species, whereas aquatic vegetation removal was favourable for some fish species, such as the endemic Cichlasoma bartoni, however, both types of disturbance were unfavourable for other species; riparian vegetation removal was negative for both groups. Controlled tourism promotes good conditions for C. bartoni establishment. Efficient conservation measures such as limiting touristic distribution are necessary for all species, especially for the fish community, in order to conserve biodiversity in general.

Habitat preferences of birds in a montane forest mosaic in the Bamenda Highlands, Cameroon

Although the high species richness and endemism of birds in the Bamenda Highlands has attracted ornithological research for decades, most studies have been restricted to bird communities of continuous montane forests. Instead, we focused on a mosaic landscape with montane forest remnants, where the habitat preferences of birds remain unknown. We performed an assessment of habitat associations of birds in the Bamenda Highlands in the Cameroon Mountains. Using a point count census method, we detected 71 species within the study area. The most abundant species were the Northern Double-collared Sunbird Cynniris reichenowi, the Oriole Finch Linurgus olivaceus, the Common Stonechat Saxicola torquata, the Thick-billed Seed-eater Serinus burtoni, the Black-crowned Waxbill Estrilda nonnula, the Brown-backed Cisticola Cisticola chubbi and the Yellow-breasted Boubou Laniarius atroflavus. Canonical correspondence analysis revealed that the most important environmental gradient structuring the bird community follows the forest coverage. We found that both endemic and non-endemic montane species are more closely associated with montane forest remnants, compared to widespread species. Endemic species are most closely dependent on continuous forest cover. However, some montane species did not show any clear habitat associations and thus can be viewed as local habitat generalists. This study shows that many restricted-range species (including endangered endemics) are able to live in fragmented landscapes, which cover a substantial part of the Bamenda Highlands. Therefore, conservation programmes should focus their action plans on these landscapes.

Bat and Bird Assemblages from Forests and Shade Cacao Plantations in Two Contrasting Landscapes in the Atlantic Forest of Southern Bahia, Brazil

In the core region of Brazilian cocoa production, shade cacao plantations (so-called cabrucas) are important components of regional landscapes, constituting potential habitat for a vast array of the regional biota. This research focuses on the ability of cabrucas to harbor bird and bat species in two nearby districts – Una and Ilheus – with contrasting landscapes. At Una, cabrucas represent less than 6% of the land and are surrounded by large tracts of forest, whereas at Ilheus these shade plantations are the landscape's dominant feature. Bird and bat communities were richer in cabrucas located in Una compared to nearby forest, while cabrucas from the Ilheus landscape were significantly poorer in species than nearby forest fragments. However, bird assemblages in cabrucas were characterized by the loss of understory specialists and the increase of more open area and generalist species, whereas forest dwellers still comprised most of the bat species reported in cabrucas. Species richness and composition differed between the two landscapes. Forest fragments and cabrucas from Ilheus harbored fewer forest-dwelling species than similar habitats in Una. Our study shows that cabrucas support high species richness of birds and bats from the native assemblages but are no surrogates for intact forests, since the presence and representativeness of some forest species apparently depends on the existence of nearby forests. A landscape dominated by cabrucas with a minor portion of native forest is unlikely to ensure long-term conservation of many target species, particularly those of major conservation concern.

Preferencias de hábitat, densidad y diversidad de las comunidades de aves en Tenerife (Islas Canarias)

Species–specific habitat preferences, density and species richness of bird communities in Teneriffe (Canary Islands) Bird distribution and abundance are described and analyzed in Teneriffe (Canary Islands). Inter–habitat differences in density, diversity and species richness are shown in table 1. Figure 2 shows the main determinants of bird species richness in Teneriffe, and tables 2 and 3 and figure 3 show the species–specific patterns of spatial variation abundance (more detailed for Anthus berthelotii, Fringilla coelebs canariensis, Fringilla teydea, Parus caeruleus teneriffae, Phylloscopus canariensis, Regulus teneriffae, Serinus canarius and Turdus merula cabrerae). Deeply transformed environments due to human impact (urban habitats, agricultural mosaics, banana plantations) have high bird densities and species richness, even higher than those measured in native, unmodified habitats such as laurel forests or mature pinewoods. Urban environments in Teneriffe are very permeable to native bird fauna, as they have been occupied by many widespread endemic species/subspecies. Many of the endemic, well defined species or subspecies of island birds have high population densities within native, untransformed habitats. Density compensation and niche expansion is not a common phenomenon in the avifauna of Teneriffe. Nevertheless, all species/subspecies broadening the inter–habitat or altitudinal distribution are endemic of the Canary Islands.

Habitat Composition and Bird Diversity in Managed Boreal Forests

This study investigated the occurrence of 25 forest bird species in relation to stand and landscape habitat composition in managed boreal forests in central Sweden. The number of species in 10 km transects was positively correlated to the proportions of forest > 40 yrs and Mixed forest >40 yrs, as well as the number of fragments of the latter, while negatively correlated to the proportions of clear-cuts and young forest. Transects with >60% older forest including > 6% mixed habitats showed the highest number of bird species and individuals. The positive effect on species numbers of mixed forest was stronger in the study area where deciduous rich habitats were generally less abundant. Bird species richness in points of similar habitat was negatively correlated to the degree of fragmentation of the surrounding older forest. However, in a species-by-species analysis at the transect level no effects of fragmentation were found. The number of bird species at points was positively influenced by the increase from 0 to 5% deciduous trees, while no effect of higher deciduous site proportions showed. The hazel grouse (Bonasa bonasia) appeared as a significant indicator of high bird diversity at the transect (landscape) level, by all methods used. However, the conclusion was reached that forests where the hazel grouse, blue tit (Parus caeruleus), treecreeper (Certia familiaris), jay (Garrulus glandarius) and capercaillie (Tetrao urogallus) are present are most likely to hold the potential for high bird species richness.

Use of Forested Habitat by Breeding Birds in the Gulf Coastal Plain

Abstract I compared birds present during the breeding season in four forest types in the Conecuh National Forest located on the Gulf Coastal Plain in Alabama: (1) longleaf pine (Pinus palustris) that had been subject to several recent burns, (2) longleaf pine that had been subject to few or no recent burns, (3) planted slash pine (P. elliottii), and (4) various forested wetland habitats ranging from stream-side riparian habitat to cypress (Taxodium distichum) ponds. I found significantly higher total individuals and significantly higher bird species richness in the two natural forest types—burned longleaf pine and riparian habitats—than either unburned longleaf or slash pine. To maintain greatest diversity and abundance of birds, managers of forests on the Gulf Coastal Plain should (1)preserve wetland habitat, (2) not convert stands of longleaf pine to stands of slash pine, and (3) regularly burn longleaf pine stands. South. J. Appl. For. 22(3):133-137.

Bird Population Patterns in Forest Edge and Strip Vegetation at Remington Farms, Maryland

Bird populations in Japanese multiflora rose (Rosa multiflora) and tall fescue (Festuca arundinacea) plantings and forest edge habitats adjacent to cultivated fields were examined. Bird species richness, abundance, and diversity were calculated for 6 management situations-forest edge, forest edge with a rose hedgerow, tall fescue waterway, rose hedgerow waterway, rose hedgerow with an unmowed tall fescue strip, and rose hedgerow with a mowed fescue strip. The hedgerow-forest edges had higher bird species richness, abundance, and diversity than the open forest edges. Differences between sites were greatest in winter and early spring. In late spring/summer, several mixed habitat or edge bird species were detected in the hedgerow-forest edges that were absent or seldom observed in the open forest edges. The addition of edge species was also responsible for the fall, winter, and early spring differences. Avian use of the tall fescue waterways was low in all seasons and much lower than the rose hedgerow waterways. Avian use of rose hedgerows with grass borders was not greatly affected by mowing the 7-9-m wide tall fescue border. Wintering birds concentrated in rose hedgerows apparently as a result of the lack of dense shrub cover in other habitats. J. WILDL. MANAGE. 46(4):933-944 Strips of Japanese multiflora rose and tall (Kentucky 31) fescue were planted on Remington Farms in the late 1950's, most extensively along roads. Of 10.2 km of rose hedgerows, 90% were planted between cultivated fields and surfaced roads (Burger and Linduska 1967), and 50% have a grass border (primarily tall fescue) between them and the road. Multiflora rose hedgerows also were planted along forests and between cultivated fields. Grass waterways consisting primarily of tall fescue additionally were developed between fields. A study of Remington Farms' strip plantings was undertaken to determine seasonal patterns of use by birds of edge and strip plantings and evaluate the effect of habitat juxtaposi-

Avifauna del Caribe sur asociada a ecosistemas alterados en Limón, Costa Rica

Southern Caribbean avifauna associated with altered ecosystems in Limón, Costa Rica. The Caribbean coast of Costa Rica, one of the areas with higher bird species richness in the country, is the main migratory route in Central America. We sampled the coast with visual counts (April-October 2002) and counted 1 639 individuals of 123 species in 14 sample sites from Moin to Cahuita. The most common species were Psarocolius montezuma (Montezuma Oropendola), Ramphocelus passerinii (Passerini's Tanager) and Oryzoborus funereus (Thick-billed Seed-Finch). Most were in cattle land with isolated trees, followed by rivers and streams and the logged forest. Penshurt had the highest relative abundance, followed by Miravalles and Tuba Creek; the site with the lowest relative abundance was Tomatal. A cluster model indicated significant differences in avifauna composition. Pastures with trees, gardens, and mixed stands were the most diverse and had more birds. Vulnerable forest species occur in these forest remnants that are important for their conservation.