Seasonal and Interspecific Variation in Frugivory by a Mixed Resident-Migrant Overwintering Songbird Community

Many temperate passerine bird species switch from diets of mostly invertebrates in the spring and summer to diets that include fruit and seeds in the fall and winter. However, relatively few studies have quantified diet composition or the extent of seasonal shifts during the non-breeding period, particularly among species and across communities with both residents and migrants. We measured carbon and nitrogen stable isotope values in food items (fruits, C3 and C4 seeds, and insects from various trophic levels and plant communities) and in multiple tissues (feathers and plasma/whole blood) from 11 species of songbirds wintering in the southeastern U.S. We combined these diet and tissue values with empirically derived discrimination factors and used concentration-dependent mixing models to quantify seasonal diet shifts. We also validated mixing model results with data from fecal samples. Diets in this bird community, as delineated N and C isotopic space, diverged in the fall and winter relative to the summer as consumption of fruits and seeds increased. Across this songbird community, estimated contributions of fruit to plasma/whole blood increased from 16.2 ± 7.5% in the fall (mean ± SD; range: 4–26%) to 21.7 ± 10.3% (range: 9–37%) in the winter, while contributions of seeds increased from 29.4 ± 2.6% (range: 28–32%) in the fall to 36.6 ± 4.8% (range: 32–42%) in the winter. Fecal data showed qualitatively similar trends to mixing models, but consistently estimated higher contributions of fruit. Our work indicates that fruits and seeds constitute substantial sources of sustenance for non-breeding songbirds, there is considerable separation of resource use among species in the fall and winter, and fecal estimates of contributions to songbird tissues should be interpreted cautiously.

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Changes in Species Composition of Birds and Declining Number of Breeding Territories over 40 Years in a Nature Conservation Area in Southwest Germany

Diversity ◽

10.3390/d10030097 ◽

2018 ◽

Vol 10 (3) ◽

pp. 97 ◽

Cited By ~ 3

Author(s):

Fabian Schrauth ◽

Michael Wink

Keyword(s):

Nature Conservation ◽

Bird Community ◽

Breeding Birds ◽

Trophic Levels ◽

Breeding Period ◽

Insectivorous Birds ◽

Breeding Bird ◽

Conservation Area ◽

Insect Populations ◽

Southwest Germany

Global loss of biodiversity is occurring at an alarming rate and is a major issue in current times. Long-term studies offer the possibility to analyse changes in biodiversity and allow assessments of anthropogenic interventions in ecosystems. At present, various studies in most countries show partially strong declines of insect populations. Due to their role as a food source for many organisms it is assumed that declines of insect abundance might have effects on higher trophic levels like insectivorous birds. For reliable statements on relationships between food availability and population trends, systematic and extensive records of breeding birds are necessary. In this study, we analysed the changes in the range of species, biodiversity, and abundance of a breeding bird community over 43 years in a large nature conservation area in southwest Germany (“Lampertheimer Altrhein” near Mannheim). Since 1974, considerable changes in the spectrum of breeding birds have been found, but the overall biodiversity index did not change. Furthermore, 70% of the investigated species showed decreasing numbers of breeding bird territories, and the overall number of territories across species declined by more than 65%. A classification based on the main diet during the breeding period and habitat use revealed strong declines for insectivorous birds in the study area, especially in wetland and open cultivated landscapes.

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The Effects of Post-Fire Management on Bird Community Succession

International Journal of Wildland Fire ◽

10.1071/wf9970335 ◽

1997 ◽

Vol 7 (4) ◽

pp. 335 ◽

Cited By ~ 20

Author(s):

I Izhaki ◽

M Adar

Keyword(s):

Pinus Halepensis ◽

Bird Species ◽

Bird Community ◽

Passerine Bird ◽

Bird Diversity ◽

Avian Community ◽

Wild Fire ◽

Logged Forest ◽

The Relationship ◽

Avian Community Structure

In September 1989 a wild fire burned over 300 ha of pine (Pinus halepensis) forest on Mt. Carmel, Israel. In winter 1990, logging took place on several burned plots. Since then, nonbreeding bird communities were censused in unburned plots, in burned plots and in burned logged plots. Canonical correspondence analysis was used to investigate the relationship between bird composition, post-fire managements and time since fire. Thirty-three species of passerine bird were recorded during fall, winter and spring (1991-1994). The most significant differences in avian community structure appeared between the unburned forest and the burned logged forest, and between the first period (1-2 years) post-fire and the following period (3-5 years post-fire). In general, the number of bird species in the ecosystem was increased as the result of imposing different post-fire managements. Therefore, creating a mosaic of different type of habitats contributed in maintaining high bird diversity.

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Testing the Likeable, Therefore Abundant Hypothesis: Bird Species Likeability by Urban Residents Varies Significantly with Species Traits

Land ◽

10.3390/land10050487 ◽

2021 ◽

Vol 10 (5) ◽

pp. 487

Author(s):

Lillian Collins ◽

Grant D. Paton ◽

Sara A. Gagné

Keyword(s):

Undergraduate Students ◽

Species Conservation ◽

Bird Species ◽

Bird Community ◽

Species Traits ◽

Community Change ◽

Habitat Availability ◽

Urban Residents ◽

Behavioral Traits

The urbanization of landscapes filters bird communities to favor particular species traits, driven in part by the changes that homeowners make to the amount and quality of habitat in yards. We suggest that an ultimate driver of these proximate mechanisms underlying bird community change with respect to urbanization is the likeability of species traits by urban residents. We hypothesize that bird species likeability, modulated by species traits, influences the degree to which homeowners alter the availability and quality of habitat on their properties and thereby affects species population sizes in urbanized landscapes. We refer to this new hypothesis as the Likeable, therefore Abundant Hypothesis. The Likeable, therefore Abundant Hypothesis predicts that (1) bird species likeability varies with species morphological and behavioral traits, (2) homeowners use trait-based likeability as a motivator to modify habitat availability and quality on their properties, and (3) residential habitat availability and quality influences species populations at landscape scales. We tested the first prediction of the Likeable, therefore Abundant Hypothesis using a survey of 298 undergraduate students at the University of North Carolina at Charlotte who were asked to rank their preferences for 85 forest generalist and edge/open country songbird species grouped according to 10 morphological and behavioral traits. Survey respondents preferred very small, primarily blue or black species that are insectivorous, aerial or bark foragers, residents, and culturally unimportant. On the other hand, respondents disliked large or very large, primarily yellow or orange species that forage on the ground and/or forage by flycatching, are migratory, and are culturally important. If the Likeable, therefore Abundant Hypothesis is true, natural resource managers and planners could capitalize on the high likeability of species that are nevertheless negatively affected by urbanization to convince homeowners and residents to actively manage their properties for species conservation.

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Female song in the Cyprus Wheatear Oenanthe cypriaca

Journal of Ornithology ◽

10.1007/s10336-021-01902-z ◽

2021 ◽

Author(s):

Robert Patchett ◽

Alexander N. G. Kirschel ◽

Joanna Robins King ◽

Patrick Styles ◽

Will Cresswell

Keyword(s):

Breeding Season ◽

Bird Species ◽

Breeding Period ◽

Territorial Defence ◽

Multiple Functions ◽

Male Song ◽

Female Song ◽

Mate Acquisition

AbstractFemale song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition.

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Fire and Mechanical Forest Management Treatments Support Different Portions of the Bird Community in Fire-Suppressed Forests

Forests ◽

10.3390/f12020150 ◽

2021 ◽

Vol 12 (2) ◽

pp. 150

Author(s):

Lance Jay Roberts ◽

Ryan Burnett ◽

Alissa Fogg

Keyword(s):

Sierra Nevada ◽

Fire Severity ◽

Bird Species ◽

Bird Community ◽

Fire Disturbance ◽

Long Term Effects ◽

High Severity ◽

Commercial Thinning ◽

Silvicultural Management ◽

Total Community

Silvicultural treatments, fire, and insect outbreaks are the primary disturbance events currently affecting forests in the Sierra Nevada Mountains of California, a region where plants and wildlife are highly adapted to a frequent-fire disturbance regime that has been suppressed for decades. Although the effects of both fire and silviculture on wildlife have been studied by many, there are few studies that directly compare their long-term effects on wildlife communities. We conducted avian point counts from 2010 to 2019 at 1987 in situ field survey locations across eight national forests and collected fire and silvicultural treatment data from 1987 to 2016, resulting in a 20-year post-disturbance chronosequence. We evaluated two categories of fire severity in comparison to silvicultural management (largely pre-commercial and commercial thinning treatments) as well as undisturbed locations to model their influences on abundances of 71 breeding bird species. More species (48% of the community) reached peak abundance at moderate-high-severity-fire locations than at low-severity fire (8%), silvicultural management (16%), or undisturbed (13%) locations. Total community abundance was highest in undisturbed dense forests as well as in the first few years after silvicultural management and lowest in the first few years after moderate-high-severity fire, then abundance in all types of disturbed habitats was similar by 10 years after disturbance. Even though the total community abundance was relatively low in moderate-high-severity-fire habitats, species diversity was the highest. Moderate-high-severity fire supported a unique portion of the avian community, while low-severity fire and silvicultural management were relatively similar. We conclude that a significant portion of the bird community in the Sierra Nevada region is dependent on moderate-high-severity fire and thus recommend that a prescribed and managed wildfire program that incorporates a variety of fire effects will best maintain biodiversity in this region.

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Bird community structure in natural and urbanized habitats along an altitudinal gradient in Pauri district (Garhwal Himalaya) of Uttarakhand state, India

Biologia ◽

10.2478/s11756-012-0068-z ◽

2012 ◽

Vol 67 (4) ◽

Cited By ~ 8

Author(s):

Archana Naithani ◽

Dinesh Bhatt

Keyword(s):

Community Structure ◽

Altitudinal Gradient ◽

Diversity Index ◽

Bird Species ◽

Bird Community ◽

High Elevation ◽

Base Line ◽

Natural Habitats ◽

Forest Habitat ◽

Rarefaction Analysis

AbstractIn the Indian subcontinent there is hardly any study that compares the bird community structure of urban/suburban areas with those of forest habitat. The present survey identified diverse assemblages of birds in the Pauri district at different elevations. A total of 125 bird species belonging to 40 families including two least count species (Lophura leucomelanos and Pucrasia marcolopha) were recorded during this survey in the forest and urbanized habitats of Pauri District (Garhwal Hiamalaya) of Uttarakhand state, India. The high elevation (Pauri 1600–2100 m a.s.l.), mid elevation (Srikot-Khanda 900–1300 m a.s.l.) and low elevation (Srinagar 500–900 m a.s.l.) contributed 88.8%, 63.2% and 58.4% of the total species respectively. Rarefaction analysis and Shannon diversity index showed that the high elevation forest habitat had highest bird species richness (BSR) and bird species diversity (BSD) followed by the mid and then the low elevation forests. BSR and BSD fluctuated across seasons at all elevations but not across habitat types. Present study provides a base line data about avian community composition in urbanized and natural habitats along altitudinal gradient in the study area. This information may be useful to the conservation biologists for the better management and conservation of the avifauna in the Western Himalaya, a part of one of the hot biodiversity spots of the world.

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Effects of the Introduction of Pied Flycatchers Ficedula hypoleuca on the Composition of a Passerine Bird Community

Ornis Scandinavica ◽

10.2307/3676218 ◽

1972 ◽

Vol 3 (2) ◽

pp. 79 ◽

Cited By ~ 20

Author(s):

Anders Enemar ◽

Bengt Sjostrand

Keyword(s):

Bird Community ◽

Passerine Bird ◽

Ficedula Hypoleuca

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Influence of cliffs on bird community diversity

Canadian Journal of Zoology ◽

10.1139/z97-195 ◽

1998 ◽

Vol 76 (2) ◽

pp. 278-287 ◽

Cited By ~ 10

Author(s):

J D Matheson ◽

D W Larson

Keyword(s):

Bird Species ◽

Bird Community ◽

Community Diversity ◽

Bird Species Richness ◽

Narrow Component ◽

Habitat Features ◽

Habitat Mosaic ◽

The North ◽

Talus Slope ◽

Additive Influence

Cliffs along the Niagara Escarpment in Ontario, Canada, support a long, narrow presettlement forest that includes three distinct geomorphic and vegetation zones: cliff edge, cliff face, and talus slope. This unique landform provides an opportunity to evaluate differences in bird communities between the escarpment and adjacent forest relative to habitat features. We sampled forest birds 12 times during the summer of 1994 in plots located in plateau forests, on talus slope, at cliff edges, and on cliff faces. Eleven habitat variables considered important to birds were also sampled in the plots. We arranged plots along six randomly spaced transects at a south site and a north site. Both sites had the consistent habitat heterogeneity considered important to birds. Bird species richness and composition responded to this heterogeneity, but differently at each site: plateau deciduous forests always had the lowest richness and the simplest species composition, whereas both cliff edges and talus slopes had a higher diversity of birds. Cliff faces had large numbers of species in the south but smaller numbers in the north. Escarpment zones form a habitat mosaic that supports many species not found in the adjacent forest and is consistent with the effect of habitat edge. The results suggest that cliffs represent a significant additive influence on avian biodiversity, even when the cliff is a very narrow component of the landscape.

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