Can guava monocultures (Psidium guajava L.) function as refuge for bird conservation?

Agricultural intensification negatively affects bird communities, and the response of birds to these changes varies from those that survive and increase their populations (disturb-tolerant species) to those that cannot adapt to new conditions and are regionally extinct (disturb-sensitive species). Thus, the present study sought to investigate the bird community in 39 guava orchards in the semiarid region of the state of Sergipe, northeast Brazil. Field observations were made between July and October 2017, through a one-hour visit to each orchard. Samplings were conducted using the MacKinnon’s List method. In addition to bird sampling, walks were carried out in the orchards to observe nesting. Seventy-six species of birds belonging to 30 families were recorded using the guava orchards. The most frequent species were Vanellus chilensis, Columbina talpacoti, Columbina picui, Crotophaga ani, Pitangus sulphuratus and Sporophila albogularis. Of the 186 nests recorded in the orchards, the majority (n = 144 nests; 77.4%) belonged to Columbina picui, Columbina talpacoti and Columbina minuta. The results demonstrate that the bird community in the guava orchards is formed only by disturb-tolerant species, showing that the studied guava orchards are not favorable to the conservation of disturb-sensitive birds of the Caatinga domain.

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Conserving native trees increases native bird diversity and community composition on commercial office developments

Journal of Urban Ecology ◽

10.1093/jue/juaa033 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Karen Dyson

Keyword(s):

Community Composition ◽

Environmental Gradients ◽

Bird Species ◽

Bird Community ◽

Bird Communities ◽

Bird Diversity ◽

Bird Conservation ◽

Tree Protection ◽

Matrix Habitat ◽

Site Use

Abstract In cities, woody vegetation provides critical shelter, nesting and foraging habitat for bird species of interest. Human actions—including development and landscaping choices—determine vegetation community composition and structure, making these choices critically important to urban bird conservation. A better understanding of how bird communities are impacted by parcel-scale actions can help guide policy and management best practices to improve matrix habitat quality and quantity. Here, I examined how bird habitat use varies along a vegetation gradient created by different development and landscaping choices. I surveyed 20 commercial office developments near Seattle in the Puget Trough region of Washington, USA selected using stratified random sampling, where I quantified bird communities and observed feeding behavior. I used GLMM and PERMANOVA models with data likelihood metrics to identify the best supported variables for bird site use, along with TITAN models to identify changes in community composition along environmental gradients. I found that measures of bird effective species richness and bird community are positively influenced by the presence of more native conifers, including the presence of a stand predating development and the height and density of native conifers. Measures of the native bird community are negatively influenced by higher non-native tree density. In contrast to prior research, top-down landscape-scale variables did not explain variation in measures of the bird community on office developments. Importantly, I found that birds are associated with the same habitat on office developments as observed elsewhere. Together, my findings suggest an important role for developers, land owners, landscape architects, and tree protection policy in bird conservation.

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A comparison of bird communities in the anthropogenic and natural-tree fall gaps of a reduced-impact logged subtropical forest in Bolivia

Bird Conservation International ◽

10.1017/s0959270908000117 ◽

2008 ◽

Vol 18 (2) ◽

pp. 129-143 ◽

Cited By ~ 6

Author(s):

Adam Felton ◽

Jeff T. Wood ◽

Annika M. Felton ◽

David B. Lindenmayer ◽

Bennett A. Hennessey

Keyword(s):

Community Composition ◽

Tree Species ◽

Bird Community ◽

Subtropical Forest ◽

Bird Communities ◽

The Other ◽

Sensitive Species ◽

Significant Difference ◽

Logged Forest ◽

Reduced Impact Logging

AbstractWe studied bird community composition and abundance within four vegetation and disturbance categories located within selectively logged and unlogged forest in a Bolivian subtropical lowland forestry concession. The logged forest was subject to reduced-impact logging between 1 and 4 years prior to our study. The four categories were: 1) ‘gap’ points possessing natural or anthropogenic tree-fall gaps; 2) ‘target’ points with one of five commercial tree species of harvestable size; 3) ‘future’ points possessing a commercial tree below harvestable size and 4) ‘non-target’ points not possessing harvestable tree species. The bird community composition of logging gaps significantly differed from that found within natural tree-fall gaps in the unlogged forest P< 0.05. Species richness was higher in natural tree-fall gaps than in anthropogenic gaps. Furthermore, a higher proportion of disturbance sensitive species were associated with natural-tree fall gaps, whereas a higher proportion of disturbance tolerant species were associated with anthropogenic gaps. No significant difference was detected in the bird community composition for the other three vegetation categories surveyed. We discuss the conservation and silvicultural repercussions of these results.

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Composition and structure of bird communities in vegetational gradients of Bodoquena Mountains, western Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201620140723 ◽

2016 ◽

Vol 88 (1) ◽

pp. 211-225 ◽

Cited By ~ 7

Author(s):

MAURICIO N. GODOI ◽

FRANCO L. SOUZA ◽

RUDI R. LAPS ◽

DANILO B. RIBEIRO

Keyword(s):

Vegetation Type ◽

Bird Species ◽

Bird Community ◽

Bird Communities ◽

Bird Diversity ◽

Bird Conservation ◽

Natural Habitats ◽

Bird Abundance ◽

Point Counts ◽

Composition And Structure

ABSTRACT The informations of bird species distribution in different habitats and the structure of their communities are crucial for bird conservation. We tested the differences in composition, richness and abundance of birds in different phytophysiognomies at Bodoquena Mountains, western Brazil, and we demonstrated the variations in richness and abundance of birds between different trophic groups. Sampling was conducted between July 2011 and June 2012 in 200 point counts arranged in the study area. A total of 3350 contacts were obtained belonging to 156 bird species. Woodland savannas, seasonal forests and arboreal savannas had higher bird abundance and richness, while riparian forests, clean pastures and dirty pastures had smaller values of these parameters. The bird community was organized according to local vegetational gradient, with communities of forests, open areas and savannas, although many species occurred in more than one vegetation type. The insectivorous, omnivorous, frugivorous and gramnivorous birds composed most of the community. These data showed how important environmental heterogeneity is to bird communities. Furthermore, the presence of extensive patches of natural habitats, the small distance between these patches and the permeability of pastures, with high arboreal and shrubby cover, are indicated as important factors to maintain the bird diversity.

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The impact of Sosnowsky’s Hogweed on feeding guilds of birds

Journal of Ornithology ◽

10.1007/s10336-021-01898-6 ◽

2021 ◽

Author(s):

Emilia Grzędzicka ◽

Jiří Reif

Keyword(s):

Negative Impact ◽

Bird Community ◽

Plant Invasions ◽

Bird Communities ◽

Feeding Guilds ◽

Guild Structure ◽

Feeding Guild ◽

Potential Impact ◽

Underlying Mechanisms ◽

The Impact

AbstractPlant invasions alter bird community composition worldwide, but the underlying mechanisms still require exploration. The investigation of feeding guild structure of bird communities can be informative in respect to the potential impact of invasion features on the availability of food for birds. For this purpose, we focused on determining the influence of the invasive Sosnowsky’s Hogweed Heracleum sosnowskyi on the abundance of birds from various feeding guilds. In spring and summer 2019, birds were counted three times on 52 pairs of sites (control + Heracleum) in southern Poland, at various stages of Sosnowsky’s Hogweed development (i.e. sprouting, full growth and flowering, all corresponding to respective bird counts). We have shown that the presence of invader negatively affected the abundance of birds from all feeding guilds. However, a closer examination of the invaded sites uncovered that responses of particular guilds differed in respect to development stages expressed by a set of characteristics of the invader. Ground and herb insectivores were more common on plots with a higher number of the invader, while the abundance of bush and tree insectivores was negatively correlated with hogweeds’ height. Granivores were not affected by the invader’s features, while the abundance of omnivores was negatively related to the number of flowering hogweeds. Besides showing the general negative impact of the invader on different feeding guilds, our research has shown that certain aspects of Sosnowsky’s Hogweed invasion may support or depress occurrence of different birds on invaded plots. Knowledge of these aspects may facilitate our capacity for coping with challenges the invasive plants put in front of bird conservationists.

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Richness, composition and trophic groups of an avian community in the Pernambuco Endemism Centre, Alagoas, Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201420130129 ◽

2014 ◽

Vol 86 (3) ◽

pp. 1207-1220 ◽

Cited By ~ 3

Author(s):

GUILHERME S. TOLEDO-LIMA ◽

PHOEVE MACARIO ◽

RACHEL M. DE LYRA-NEVES ◽

BRUNO P. TEIXEIRA ◽

LUIZ A.F. DE LIMA ◽

...

Keyword(s):

Forest Cover ◽

Bird Community ◽

Northeastern Brazil ◽

Forest Fragments ◽

Trophic Groups ◽

Negative Consequences ◽

Sensitive Species ◽

Avian Community ◽

Breeding Sites ◽

Surrounding Matrix

In northeastern Brazil, the reduction of the natural forest cover to a series of small, isolated fragments has had negative consequences for the local avian fauna, in particular, a loss of the more specialized species, while the populations of some generalists have tended to increase. The present study focuses on the composition and trophic groups of a bird community on a farm in the northeastern Brazilian state of Alagoas. Monthly surveys were conducted between November 2008 and October 2009, based on mist-netting and systematic observations. Overall, 112 species were recorded, of which 76 were associated with the two forest fragments surveyed, while all the others were observed exclusively in the surrounding matrix of pasture and orchards. The bird community presented a predominance of insectivorous species, followed by omnivores. However, specialized trunk-creeping and understory insectivores accounted for only around 15% of the species in this feeding category. The reduced diversity of other guilds and species with more specialized diets, and the complete absence of sensitive species such as large parrots and raptors, reflects the severe fragmentation and degradation of the local forests, which has greatly reduced the availability of dietary resources and breeding sites.

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Differential tolerance to ultraviolet-B light and photoenzymatic repair in cladocerans from a Chilean lake

Marine and Freshwater Research ◽

10.1071/mf03027 ◽

2004 ◽

Vol 55 (2) ◽

pp. 193 ◽

Cited By ~ 11

Author(s):

Rodrigo Ramos-Jiliberto ◽

Patricia Dauelsberg ◽

Luis R. Zúñiga

Keyword(s):

Treatment Group ◽

Visible Light ◽

Ceriodaphnia Dubia ◽

Ultraviolet B ◽

Sensitive Species ◽

Tolerant Species ◽

Cladoceran Species ◽

Different Doses

In the present study, the sensitivity of four coexisting cladoceran species to ultraviolet (UV)-B radiation was evaluated. First, the LD50 under conditions inhibiting the action of photoenzymatic repair was calculated by exposing cladocerans to different doses of UV-B light only. Animals in another treatment group were exposed to both UV-B and visible light, which allows for photoenzymatic repair. Photoenzymatic repair contributed significantly towards the degree of total tolerance to UV-B light in all groups of cladocerans, although the magnitude of the contribution varied among species. When no photoenzymatic repair was allowed, the most tolerant species was Moina micrura, followed by Daphnia ambigua and Ceriodaphnia dubia, with Diaphanosoma chilense being the most sensitive species. Under conditions permitting the action of photorepair, M. micrura was again the most tolerant species to UV-B light. Ceriodaphnia dubia showed an intermediate tolerance value, whereas D. chilense and D. ambigua were the least tolerant species, with no significant differences between them. Adults and juveniles of C. dubia differed in their sensitivity to UV-B light under conditions with and without photorepair.

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Status, diversity and trends of the bird communities in Volcanoes National Park and surrounds, Rwanda

Bird Conservation International ◽

10.1017/s0959270919000121 ◽

2019 ◽

Vol 30 (1) ◽

pp. 1-20 ◽

Cited By ~ 1

Author(s):

MIA A. DERHÉ ◽

DEO TUYISINGIZE ◽

WINNIE ECKARDT ◽

FAIDA EMMANUEL ◽

TARA STOINSKI

Keyword(s):

National Parks ◽

National Park ◽

Mixed Forest ◽

Basal Area ◽

Bird Community ◽

Bird Communities ◽

Population Pressure ◽

Bird Diversity ◽

Albertine Rift ◽

1960S And 1970S

SummaryThe Volcanoes National Park (VNP) in Rwanda, part of the Virunga massif in the Albertine Rift region, boasts some of Rwanda’s best remaining natural vegetation and is home to many endangered and endemic species. The park has suffered from high levels of degradation and destruction, reducing in size by 50% during the 1960s and 1970s, and remains under threat from illegal activities, human population pressure and climate change. This study is the first to investigate the status and trends of bird communities in the VNP, using a multi-year dataset. We use a five-year dataset, totalling over 3,200 point-counts, both within and around the VNP, to assess the conservation value of the VNP for birds in comparison with other national parks and non-protected areas. We assess bird communities and population trends within and around the parks and identify important habitat factors for birds within the VNP. We found that the VNP hosts a unique bird community compared to other localities, with several Albertine Rift endemics and threatened species occurring in the VNP. Hagenia/ Hypericum woodland, herbaceous vegetation, brush ridge and mixed forest host the highest levels of bird diversity in the VNP, whilst the park’s waterbodies provide key habitat for the endangered Albertine Rift endemic Grauer’s Swamp-warbler (Bradypterus graueri). Elevation had a negative effect on bird diversity in the VNP, whilst the basal area of dead trees, Hagenia and vines had a positive effect. Both inside and outside the VNP, there was a significant decline in abundance and species richness over the sampling years; however, we advocate for further monitoring to confirm these trends. Based on our findings, we recommend effective, targeted management of key habitats for birds within the park, including those identified in this study, in order to mitigate bird declines and conserve the unique bird communities in the VNP.

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Scale dependence of biotic homogenisation by urbanisation: a comparison of urban bird communities between central Argentina and northern Finland

European Journal of Ecology ◽

10.1515/eje-2017-0011 ◽

2017 ◽

Vol 3 (2) ◽

pp. 1-18 ◽

Cited By ~ 9

Author(s):

Lucas M. Leveau ◽

Jukka Jokimäki ◽

Marja-Liisa Kaisanlahti-Jokimäki

Keyword(s):

Species Turnover ◽

Regional Scale ◽

Bird Species ◽

Bird Community ◽

Bird Communities ◽

Urban Habitats ◽

Suburban Areas ◽

Biotic Homogenisation ◽

Community Dissimilarity ◽

The Town

AbstractRecent studies showed contrasting results about the homogenising force of urbanisation on bird community composition at large and regional scales. We studied whether urbanisation promotes the homogenisation of wintering bird communities and if this varies when comparing towns located within a specific region and towns located in two different biomes of two countries. We used both similarity indices based on the presence/absence data and the abundance data in comparing communities. Processes governing bird community dissimilarity between urbanisation levels were examined with the partitioning of Sörensen index in species turnover and nestedness. We made bird surveys in town centres and suburban habitats of three cities located in the Pampean region of Argentina and in the boreal region of Finland using a single-visit study plot method. Rarefacted species richness did not differ amongst the town centres between the countries, but it was higher in the suburban areas of Argentina than in Finland. At the country-level comparison, we found a higher similarity amongst the town centres than amongst the suburban areas; whereas at the regional comparison, similarity between town centres was comparable to the similarity between suburban areas. The use of an abundance-based index produced a higher similarity between town centre communities of both countries than when using a presence-based index. The dissimilarity between habitats in Argentina was related to nestedness and to species turnover in Finland. Our results indicate that urban-based biotic homogenisation of bird communities is dependent on the scale used, being more evident when comparing cities of different biomes where the same and abundant bird species, such as sparrows and doves, dominate. At the regional scale, quite a high beta-diversity can still be found within urban habitats. Processes of community dissimilarity between urban habitats may differ according to the regional pool of species, being more related to nestedness toward the tropics.

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The influence of aluminium on phosphate sorption by whole plants and excised roots of some pasture legumes

Australian Journal of Agricultural Research ◽

10.1071/ar9730341 ◽

1973 ◽

Vol 24 (3) ◽

pp. 341 ◽

Cited By ~ 29

Author(s):

CS Andrew ◽

PJVanden Berg

Keyword(s):

Dry Matter ◽

Phosphorus Uptake ◽

Dry Matter Production ◽

Unit Weight ◽

Phosphorus Concentration ◽

Sensitive Species ◽

Pasture Legumes ◽

Tolerant Species ◽

Matter Production ◽

Whole Plants

The effects of aluminium (0, 0.5, 1.0, and 2.0 p.p.m.) on dry matter production and subsequent short-term uptake and translocation of phosphorus in whole plants, and on the uptake of phosphorus by excised roots, of six tropical pasture legumes were ascertained. Macroptilium lathyroides, Desrnodiurn uncinaturn, Lotononis bainesii, and Stylosanthes hurnilis were tolerant species in terms of effects on dry matter production. Glycine wightii was a sensitive species and Medicago sativa a very sensitive one. In the whole plant study, plants were grown in Solution culture with a phosphorus concentration of 2 p.p.m., under the above aluminium treatments. Aluminium increased the subsequent uptake of phosphorus (tops+roots) in all species (phosphorus substrate concentration 1 x 10-5M labelled with 32P, 1 and 3 hr uptake periods). Phosphorus uptake in the tops of the four tolerant species was increased by aluminium treatment, and in the two sensitive species it uas reduced. In both the absence and presence of applied aluminium, L. bainesii was the most efficient species per unit weight of root tissue in sorbing total phosphorus, and in addition had the highest efficiency of translocation of phosphorus from roots to tops. S. humilis was also an efficient species. In the excised root study, addition of aluminium to the solution enhanced the sorption of phosphorus by all species. The enhancement was greater in a relatively strong phosphorus solution (2 x 10-4 M) than in a dilute solution (1 x 10-4). The sorption of phosphorus by excised roots of S. humilis from dilute and relatively strong phosphorus substrates was greater than that of other species, both in the absence and presence of added aluminium. L. bainesii was omitted from the excised root experiments.

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