Effects of forest heterogeneity on occurrence and abundance of the scale-backed antbird, Hylophylax poecilinotus (Aves: Thamnophilidae), in the Amazon forest

Recently, a significant number of studies on neotropical forest bird communities have focused on factors influencing their richness, abundance, and habitat selection. However, few of them have considered populations or individual species, and how habitat structure affects their distribution and abundance. In this study, we investigated how the combined effects of some forest structure components affect the occurrence and abundance of a resident bird species, the scale-backed antbird Hylophylax poecilinotus (Cabanis, 1847). We tested the null hypothesis of no difference between the variation in forest structure components at locations where birds occurred and at locations where they did not. In a pristine Terra Firme forest at the Ducke Reserve, Manaus, we recorded bird occurrence and abundance using mist nets in 56 transects (1 km long each) within a 9 x 9 km trail grid covering 6400 ha. Also in the same 56 transects, we set 50 x 50 m plots and recorded the following seven components of forest structure and landscape: 1) canopy opening, 2) leaf litter, 3) tree abundance, 4) logs, 5) snags, 6) streams, and 7) elevation. We evaluated their effects on avian occurrence and abundance by using models of Multiple Logistic Regression (for bird occurrence) and Multiple Linear Regression (for bird abundance). The results suggested that H. poecilinotus occurred significantly more often in lowland areas, in areas located farther away from streams, and in areas bearing thicker leaf litter. Hylophylax poecilinotus was also more abundant in lowland areas and in areas located further away from streams. Overall, the results indicated that environmental heterogeneity produced by variation in forest structure components affects habitat use by this bird species in the Amazon forest.

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Efecto de la estacionalidad y lluvias en la avifauna del Chaco Serrano Austral, Argentina

Revista de Biología Tropical ◽

10.15517/rbt.v65i3.29434 ◽

2017 ◽

Vol 65 (3) ◽

pp. 953

Author(s):

Gustavo Alfredo Fava ◽

Juan Carlos Acosta ◽

Graciela Mirta Blanco

Keyword(s):

Bird Species ◽

Reproductive Activity ◽

Breeding Habitat ◽

Bird Abundance ◽

Group Management ◽

Natural Park ◽

Chaco Serrano ◽

Site Survey ◽

Migrant Bird ◽

Resident Bird

In subtropical regions like the Chaco Serrano (33° S), rainfall has a marked seasonality, and water flood, caused by heavy rains, may have important consequences for dependent ecosystems. Conversely, the high pressure on available resources during dry periods can also affect the fauna diversity and distribution. Even though birds have shown to be excellent ecological indicators of these shifts in the environment, currently little is known about the avifauna of the Argentine Chaco Serrano phytogeographic district. Our aim was to study the resident bird population status in the Southern Chaco Serrano, its fluctuations in richness and abundance, and its relationship to seasonal variations, in monthly and annual hydroperiods. In order to assess the resident bird status over a two year period (2011 Mar.-2013 Feb.) we carried out 18 sampling surveys during pre-breeding (spring), breeding (summer) and non breeding periods (autumn-winter), in the Northeastern part of the Valle Fértil Natural Park, San Juan province, Argentina. During each site survey, we recorded bird assemblages found in six transects, and obtained bird abundance and species diversity. A mixed general linear model was employed to evaluate relationships between the studied variables. We found a total of 98 species of birds belonging to 33 families (44 resident species, 23 spring visitors, six summer visitors, two winter visitors and 23 with scarce registers). We also registered 68 of these species in both hydroperiods, 28 only during rainy periods and only two during the dry period. Both richness and abundance showed the highest values during the pre-breeding and rainy seasons, while different tendencies were detected during the isolated monthly rainfalls. These changes in bird densities were associated with the arrival of migratory species, mainly spring visitors, and probably in relationship with their reproductive activity, and to seasonal fluctuations in food resources. The Southern Chaco Serrano is a subtropical semiarid place that seems to be an important breeding habitat for many migrant bird species, which in turn promoted seasonal changes in species density and diversity, mainly during rainy years. This work contributed to our understanding on the causes of richness and abundance variations on birds, and will contribute to this important group management and conservation in this area.

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Bushland modification and styles of urban development: their effects on birds in south-east Queensland

Wildlife Research ◽

10.1071/wr96078 ◽

1998 ◽

Vol 25 (1) ◽

pp. 41 ◽

Cited By ~ 100

Author(s):

Sven R. Sewell ◽

Carla P. Catterall

Keyword(s):

Species Richness ◽

Native Species ◽

Bird Species ◽

Individual Species ◽

Bird Abundance ◽

Bird Species Richness ◽

Forest Clearing ◽

Major Response ◽

Forest Remnants ◽

High Species Richness

Variation in bird assemblages associated with forest clearing and urbanisation in the greater Brisbane area was assessed by counting birds in sites within six habitat categories: large remnants, small remnants, no- understorey remnants, canopy suburbs (original trees present), planted suburbs, and bare suburbs. Total bird abundance and species richness were generally highest in canopy suburbs. Individual species showed many significant abundance differences among the habitat types, and were classified into three major response categories: bushland species (3 in summer, 13 in winter), tolerant species (13 in summer, 13 in winter), and suburban species (12 in summer, 11 in winter). The commonly proposed notion that urbanisation results in lowered bird species richness and increases in introduced species is broadly consistent with the observed differences between bare suburbs and large remnants. However, it does not adequately describe the situation in the planted and canopy suburbs, where there was high species richness and extremely high abundance of some native species (including noisy miners, lorikeets, friarbirds, and butcherbirds) but low abundance of a majority of the species common in the original habitats (including fantails, wrens, whistlers, and other small insectivores). Retained forest remnants are essential for the latter group. Urban plantings of prolifically flowering native species do not reverse the effects of deforestation, but promote a distinctive group of common native suburban bird species. Origins of the urban bird assemblage are discussed.

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Monitoring indicates greater resilience for birds than for mammals in Kakadu National Park, northern Australia

Wildlife Research ◽

10.1071/wr11213 ◽

2012 ◽

Vol 39 (5) ◽

pp. 397 ◽

Cited By ~ 10

Author(s):

J. C. Z. Woinarski ◽

A. Fisher ◽

M. Armstrong ◽

K. Brennan ◽

A. D. Griffiths ◽

...

Keyword(s):

National Park ◽

Fire History ◽

Regional Scale ◽

Monitoring Program ◽

Bird Species ◽

Sampling Period ◽

Fire Regimes ◽

Individual Species ◽

Mammal Species ◽

Bird Abundance

Context A previous study reported major declines for native mammal species from Kakadu National Park, over the period 2001–09. The extent to which this result may be symptomatic of more pervasive biodiversity decline was unknown. Aims Our primary aim was to describe trends in the abundance of birds in Kakadu over the period 2001–09. We assessed whether any change in bird abundance was related to the arrival of invading cane toads (Rhinella marina), and to fire regimes. Methods Birds were monitored at 136 1-ha plots in Kakadu, during the period 2001–04 and again in 2007–09. This program complemented sampling of the same plots over the same period for native mammals. Key results In contrast to the decline reported for native mammals, the richness and total abundance of birds increased over this period, and far more individual bird species increased than decreased. Fire history in the between-sampling period had little influence on trends for individual species. Interpretation of the overall positive trends for bird species in Kakadu over this period should be tempered by recognition that most of the threatened bird species present in Kakadu were unrecorded in this monitoring program, and the two threatened species for which there were sufficient records to assess trends – partridge pigeon (Geophaps smithii) and white-throated grass-wren (Amytornis woodwardi) – both declined significantly. Conclusions The current decline of the mammal fauna in this region is not reflected in trends for the region’s bird fauna. Some of the observed changes (mostly increases) in the abundance of bird species may be due to the arrival of cane toads, and some may be due to local or regional-scale climatic variation or variation in the amount of flowering. The present study provides no assurance about threatened bird species, given that most were inadequately recorded in the study (perhaps because their decline pre-dated the present study). Implications These contrasting trends between mammals and birds demonstrate the need for biodiversity monitoring programs to be broadly based. The declines of two threatened bird species over this period indicate the need for more management focus for these species.

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Monitoring of Kilum-Ijim forest bird communities: initial findings

Bird Conservation International ◽

10.1017/s0959270903003198 ◽

2003 ◽

Vol 13 (3) ◽

pp. 255-271 ◽

Cited By ~ 9

Author(s):

Philip F. Forboseh ◽

Ernest C. Keming ◽

Clement L. Toh ◽

Innocent N. B. Wultof

Keyword(s):

Structural Changes ◽

Bird Species ◽

Bird Community ◽

Montane Forest ◽

Bird Communities ◽

Individual Species ◽

Bird Abundance ◽

The Status ◽

Abundance And Diversity ◽

The Relationship

The Kilum-Ijim forest is an excellent example of the ornithological riches of the Cameroon montane forest biome. The forest is also important to over 200,000 people who exert enormous pressure on the ecosystem. In 1995, the Kilum-Ijim Forest Project began systematic monitoring of birds, with the intention of using them as indicators of the overall condition of the forest, as well as monitoring the status of individual species. Analyses of data collected in 1999–2000 demonstrated some clear differences in habitat use, suggesting suites of bird species may be indicators of changes in vegetation. However, beyond this, little is known about the response of birds to habitat modifications, or the relationship between bird abundance and diversity of other organisms at Kilum-Ijim. It is argued that the objective of assessing changes in vegetation could be more satisfactorily pursued through direct measurement of structural changes in habitats. We highlight the necessity for a shift in the programme objectives to place greater emphasis on monitoring endemic and threatened bird species for their own status and on assessing changes in the bird community as a function of changes in the vegetation.

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Die Brutvogelfauna eines Nadelwaldes der nördlichen Voralpen nach dem Sturm Lothar

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2017.0059 ◽

2017 ◽

Vol 168 (2) ◽

pp. 59-66

Author(s):

Pierre Mollet ◽

René Hardegger ◽

Res Altwegg ◽

Pius Korner ◽

Simon Birrer

Keyword(s):

Forest Succession ◽

Coniferous Forest ◽

Bird Species ◽

Individual Species ◽

Mountain Forest ◽

Breeding Bird ◽

Point Counts ◽

Federal Institute ◽

Central Switzerland ◽

Bird Fauna

Breeding bird fauna in a coniferous forest in the northern Prealps after storm Lothar In a 70-hectare large coniferous forest located on the northern edge of the Alps in central Switzerland, Canton of Obwalden, at an altitude of 1260 to 1550 metres above sea level, we surveyed the local breeding bird fauna in 2002 and 2013 by means of point counts as well as additional area searches for rare species. In December 1999, hurricane Lothar caused two large windthrow areas and several smaller areas with scattered throws in the survey range. We found a total of 48 breeding bird species, which is a very diverse species composition for a mountain forest. In the eleven years between surveys, a decline in distribution or abundance was recorded for four species, while seven species showed an increase; a further four species showed no change. For the remaining species, the data sets were too small to reliably estimate changes. A comparison with forest structure data provided by the Swiss Federal Institute of Forest, Snow and Landscape Research WSL revealed that for five bird species, the changes in distribution or abundance could be explained at least partially by forest succession. In order to obtain realistic distribution and abundance values in this kind of breeding bird survey, it is essential to collect large enough samples and to consider the detection probability of each individual species using appropriate statistical methods.

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Avian Community Response to Midrotation Herbicide Release and Prescribed Burning in Conservation Reserve Program Plantations

Southern Journal of Applied Forestry ◽

10.1093/sjaf/32.3.111 ◽

2008 ◽

Vol 32 (3) ◽

pp. 111-119 ◽

Cited By ~ 9

Author(s):

Brandon Sladek ◽

L. Burger ◽

Ian Munn

Keyword(s):

Loblolly Pine ◽

Prescribed Burning ◽

Conservation Reserve Program ◽

Volume Growth ◽

Bird Species ◽

Community Response ◽

Individual Species ◽

Avian Community ◽

Disturbance Regimes ◽

Pinus Spp

Abstract Former agricultural lands converted to pine (Pinus spp.) plantations in the Conservation Reserve Program (CRP) have potential to provide early successional (ES) habitat for many regionally declining pine/grassland and shrub-successional bird species if actively managed with appropriate disturbance regimes. One such regime is use of the selective herbicide Imazapyr (Arsenal Applicators Concentrate) and prescribed burning, which is permitted on CRP lands and cost share payments are available. This study quantified combined effects of Imazapyr and prescribed fire on the breeding season avian community characteristics and pine volume growth in thinned, midrotation afforested loblolly pine (Pinus taedaL.) plantations in Mississippi. Herbicide treatments were applied in fall of 2002 and winter burns were conducted during winter and early spring of 2002–2003. ES bird species richness was significantly greater in the treated plots compared with controls for both 2003 and 2004. Ten individual species exhibited treatment effects. These responses by ES bird species indicate that midrotation CRPplantations can provide needed ES habitat if treated with appropriate disturbance regimes.

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Amazon forest structure generates diurnal and seasonal variability in light utilization

Biogeosciences Discussions ◽

10.5194/bgd-12-19043-2015 ◽

2015 ◽

Vol 12 (23) ◽

pp. 19043-19072 ◽

Cited By ~ 4

Author(s):

D. C. Morton ◽

J. Rubio ◽

B. D. Cook ◽

J.-P. Gastellu-Etchegorry ◽

M. Longo ◽

...

Keyword(s):

Forest Structure ◽

Seasonal Variability ◽

Seasonal Changes ◽

Forest Productivity ◽

Dry Season ◽

Airborne Lidar ◽

Amazon Forest ◽

Light Saturation ◽

Light Utilization ◽

Saturation Effects

Abstract. The complex three-dimensional (3-D) structure of tropical forests generates a diversity of light environments for canopy and understory trees. Understanding diurnal and seasonal changes in light availability is critical for interpreting measurements of net ecosystem exchange and improving ecosystem models. Here, we used the Discrete Anisotropic Radiative Transfer (DART) model to simulate leaf absorption of photosynthetically active radiation (lAPAR) for an Amazon forest. The 3-D model scene was developed from airborne lidar data, and local measurements of leaf reflectance, aerosols, and PAR were used to model lAPAR under direct and diffuse illumination conditions. Simulated lAPAR under clear sky and cloudy conditions was corrected for light saturation effects to estimate light utilization, the fraction of lAPAR available for photosynthesis. Although the fraction of incoming PAR absorbed by leaves was consistent throughout the year (0.80–0.82), light utilization varied seasonally (0.67–0.74), with minimum values during the Amazon dry season. Shadowing and light saturation effects moderated potential gains in forest productivity from increasing PAR during dry season months when the diffuse fraction from clouds and aerosols was low. Comparisons between DART and other models highlighted the role of 3-D forest structure to account for seasonal changes in light utilization. Our findings highlight how directional illumination and forest 3-D structure combine to influence diurnal and seasonal variability in light utilization, independent of further changes in leaf area, leaf age, or environmental controls on canopy photosynthesis. Changing illumination geometry constitutes an alternative biophysical explanation for observed seasonality in Amazon forest productivity without changes in canopy phenology.

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Habitat and Landscape Suitability as Indicators of Bird Abundance in Created and Restored Wetlands

ISRN Ecology ◽

10.5402/2011/297684 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Jordan W. Mora ◽

John N. Mager III ◽

Douglas J. Spieles

Keyword(s):

Bird Species ◽

Land Development ◽

Logistic Models ◽

Field Measurements ◽

Road Density ◽

Bird Abundance ◽

Aerial Photos ◽

Landscape Variables ◽

Buffer Width ◽

Landscape Scales

We used aerial photography, field measurements, and bird surveys to evaluate 7 Ohio mitigation wetlands for their capacity to support avian guilds at both local and landscape scales. At the local scale, we assessed each wetland with habitat suitability indices (HSI) for eight wetland-dependent bird species as indicators for four guilds: wading, diving, dabbling, and emergent dependent. We characterized landscapes within 2.5 km of each wetland by measuring the buffer width, road density, connectedness, and anthropogenic land development. The changes in landscape variables over time were determined by comparison of aerial photos taken near the time of wetland construction and near the time of this study. Bird abundance data were poorly correlated with HSI scores but were well described with logistic models of buffer width, wetland area, and road density. Our results suggest that landscape variables are better predictors of bird abundance than HSI scores for these guilds in these wetlands.

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Hydrological niche segregation defines forest structure and drought tolerance strategies in a seasonal Amazon forest

Journal of Ecology ◽

10.1111/1365-2745.13022 ◽

2018 ◽

Vol 107 (1) ◽

pp. 318-333 ◽

Cited By ~ 37

Author(s):

Mauro Brum ◽

Matthew A. Vadeboncoeur ◽

Valeriy Ivanov ◽

Heidi Asbjornsen ◽

Scott Saleska ◽

...

Keyword(s):

Drought Tolerance ◽

Forest Structure ◽

Amazon Forest ◽

Niche Segregation

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A Fixed-radius Point Count Method for Nonbreeding and Breeding Season Use

The Auk ◽

10.1093/auk/103.3.593 ◽

1986 ◽

Vol 103 (3) ◽

pp. 593-602 ◽

Cited By ~ 306

Author(s):

Richard L. Hutto ◽

Sandra M. Pletschet ◽

Paul Hendricks

Keyword(s):

Bird Species ◽

Common Species ◽

Bird Abundance ◽

Point Count ◽

Bird Density ◽

Count Method ◽

Species Abundances ◽

Fixed Radius ◽

Point Count Method ◽

A Site

Abstract We provide a detailed description of a fixed-radius point count method that carries fewer assumptions than most of the currently popular methods of estimating bird density and that can be used during both the nonbreeding and breeding seasons. The method results in three indices of bird abundance, any of which can be used to test for differences in community composition among sites, or for differences in the abundance of a given bird species among sites. These indices are (1) the mean number of detections within 25 m of the observer, (2) the frequency of detections within 25 m of the observer, and (3) the frequency of detections regardless of distance from the observer. The overall ranking of species abundances from a site is similar among the three indices, but discrepancies occur with either rare species that are highly detectable at great distances or common species that are repulsed by, or inconspicuous when near, the observer. We argue that differences in the behavior among species will preclude an accurate ranking of species by abundance through use of this or any other counting method in current use.

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