Survival and extinction of breeding landbirds on San Cristóbal, a highly degraded island in the Galápagos

2019 ◽  
Vol 30 (3) ◽  
pp. 381-395 ◽  
Author(s):  
MICHAEL DVORAK ◽  
BIRGIT FESSL ◽  
ERWIN NEMETH ◽  
DAVID ANCHUNDIA ◽  
JAVIER COTÍN ◽  
...  
Keyword(s):  
Habitat Loss ◽  
Large Scale ◽  
Vegetation Change ◽  
Bird Species ◽  
Small Population ◽  
Santa Cruz ◽  
Present Evidence ◽  
Point Counts ◽  
Near Threatened ◽  
Better Than

SummaryWe documented the consequences of large-scale habitat loss on a community of Galápagos native bird species on San Cristóbal island, based on point counts conducted between 2010 and 2017. Surprisingly, despite considerable habitat change and a variety of other threats, the landbirds of San Cristóbal have fared much better than on the neighbouring islands Floreana or Santa Cruz. While two species went extinct very soon after human colonisation, the majority have adapted well to subsequent vegetation change and habitat loss. The endemic San Cristóbal Mockingbird Mimus melanotis is more widespread than previously thought and its population seems to be stable since the 1980s. We thus propose a change in IUCN classification from ‘Endangered’ to ‘Near threatened’. We present evidence gained by interviewing locals which suggests that a small population of the Least Vermilion Flycatcher Pyrocephalus dubius, classified as ‘Extinct’ by BirdLife International, may have persisted until very recently. Although extensive searches in 2018 and 2019 were unsuccessful, the possibility remains that a few birds may have survived in remote parts of the island. Further searches that involve the general public and other interested parties are therefore deemed necessary.

scholarly journals Diversity and status of avifauna in man-made sacred ponds of Kurukshetra, India

2018 ◽  
Vol 10 (9) ◽  
pp. 12173
Author(s):  
Parmesh Kumar ◽  
Archna Sharma
Keyword(s):  
Bird Species ◽  
Iucn Red List ◽  
Future Research ◽  
Gangetic Plains ◽  
Point Counts ◽  
Wild Fauna ◽  
Stopover Sites ◽  
Direct Observations ◽  
Religious Importance ◽  
Near Threatened

Located in the Trans-Gangetic Plains of India, Kurukshetra is dotted with a number of man-made, perennial, sacred ponds of great historical and religious importance.  These wetlands also serve as important wintering and stopover sites for birds coming from the Palearctic region.  Surveys were conducted from April 2014 to March 2015 to recordthe diversity and status of avifauna in four sacred ponds of Kurukshetra. Point counts and direct observations were used to record the bird species.  A total of 126 bird species of 98 genera belonging to 45 families and 16 orders were identified, of which 41 were winter migrants, six were summer migrants, and 79 were residents.  Anatidae (n=15) was the most common family, followed by Ardeidae (n=8), and Motacillidae and Muscicapidae (n=7 each).  Based on the guilds, 37 species were carnivorous, 36 omnivorous, 29 insectivorous, six herbivorous, six frugivorous, five granivorous, four insectivorous/nectarivorous, and three piscivorous.  Of the species recorded, five species are classified as Near Threatened and one species as Vulnerable in the IUCN Red List of Threatened Species; nine species are listed in Appendix II of Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and six species are included in Schedule I of the Indian Wildlife (Protection) Act, 1972.  We hope that this study will provide a baseline for future research on monitoring the population and seasonal changes in the bird assemblageof sacred ponds. 

Predicting the effects of grazing management on moorland bird abundance

2005 ◽  
Vol 2005 ◽  
pp. 69-69
Author(s):  
S. M. Gardner ◽  
G. M. Buchanan ◽  
J. W. Pearce-Higgins ◽  
M. C. Grant
Keyword(s):  
Large Scale ◽  
Vegetation Change ◽  
Scale Effects ◽  
Plant Competition ◽  
Bird Species ◽  
Field Studies ◽  
Grazing Management ◽  
Small Scale ◽  
Ecological Processes ◽  
Bird Abundance

Field studies of grazing management have frequently concluded that the magnitude and direction of vegetation response is dependent on initial vegetation condition. On upland heath, this dependence reflects the importance of small-scale ecological processes (e.g. plant competition), and local neighbourhood effects (e.g. spatial distribution of plant species), in driving the vegetation dynamics. These small-scale effects, together with variation in grazing patterns, increase the difficulty of deriving general rules about the effect of grazing on vegetation change from field studies. However, we need to determine the impacts of such grazing-related vegetation change upon biodiversity, (e.g. birds). For many bird species it is impractical to use experimental approaches due to low breeding densities, and the influence of other site and management effects (e.g. predator control). To predict the effect of management changes on them requires an accurate assessment of the large-scale effects of grazing management on the ecological landscape using data from small-scale field studies. This paper sets out an approach that integrates field studies with theoretical models to investigate the large-scale effects of grazing management on plant and bird communities on upland heath.

Evidence for bottom-up effects in the boreal forest: Do passerine birds respond to large-scale experimental fertilization?

1995 ◽  
Vol 73 (12) ◽  
pp. 2231-2237 ◽  
Author(s):  
Nicholas F. G. Folkard ◽  
James N. M. Smith
Keyword(s):  
Species Richness ◽  
Boreal Forest ◽  
Large Scale ◽  
Bird Species ◽  
Passerine Bird ◽  
Spatial And Temporal Variation ◽  
Bottom Up ◽  
Bird Species Richness ◽  
Point Counts ◽  
The Impact

Boreal plant communities are strongly nutrient limited, and the animals of the boreal forest may therefore experience bottom-up nutrient limitation. We conducted a 5-year experimental study of the impact of aerial nitrogen fertilization on birds of the boreal forest near Kluane Lake, southwestern Yukon, to test for such bottom-up effects. Specifically, we tested if avian abundance and species richness increased after fertilization. Variable circular-plot point counts were made to estimate bird numbers and species richness each summer from 1988 to 1992. Fertilization had no effect on abundance for the first two summers, but total abundances of the seven commonest passerine bird species increased by an average of 46% over the final 3 years. Fertilization had no effect on bird species richness. Population densities and species richness were both low at Kluane compared with patterns seen in temperate forest. Yellow-rumped warblers (Dendroica coronata), dark-eyed juncos (Junco hyemalis), and Swainson's thrushes (Catharus ustulatus) dominated the passerine community at Kluane. There was only moderate spatial and temporal variation in songbird numbers on control plots over the 5-year study period.

scholarly journals Population densities and conservation status of Norfolk Island forest birds

2012 ◽  
Vol 23 (3) ◽  
pp. 271-282 ◽  
Author(s):  
GUY DUTSON
Keyword(s):  
National Park ◽  
Conservation Status ◽  
Bird Species ◽  
Iucn Red List ◽  
Small Population ◽  
Population Densities ◽  
Point Counts ◽  
Norfolk Island ◽  
Population Sizes ◽  
Line Transects

SummaryThree weeks of intensive surveys in Norfolk Island National Park in 2009 failed to find White-chested White-eye Zosterops albogularis and it was calculated that there was a less than 17% probability that a population of 10 birds had been overlooked. The last multi-observer record of this species was in 1978, and it is recommended that the species’ IUCN Red List status of “Critically Endangered” is tagged as “Possibly Extinct”. During these surveys, the population densities of seven bird species were calculated from 352 independent point counts. Causes of imprecision and bias were investigated, suggesting a small underestimation. Other species were recorded too infrequently, or their distributions were too biased, for analysis. The population densities of the extant endemic taxa were relatively high and suggest no current declines, and the population estimates were consistent with previous studies. This study recommends monitoring most species by point counts, or line transects if resources are limited, supplemented with specific monitoring of Tasman (Norfolk Island) Parakeet Cyanoramphus cookii, Pacific Robin Petroica multicolor, Southern Boobook Ninox novaeseelandiae and seabirds. Ongoing monitoring of these birds is needed to help inform management of the National Park and the island in general, given their small population sizes and their likely susceptibility to rat and cat predation, competition from alien species and drought.

Fine-scale effects of habitat loss and fragmentation despite large-scale gene flow for some regionally declining woodland bird species

2012 ◽  
Vol 27 (6) ◽  
pp. 813-827 ◽  
Author(s):  
Katherine A. Harrisson ◽  
Alexandra Pavlova ◽  
J. Nevil Amos ◽  
Naoko Takeuchi ◽  
Alan Lill ◽  
...  
Keyword(s):  
Gene Flow ◽  
Habitat Loss ◽  
Large Scale ◽  
Scale Effects ◽  
Bird Species ◽  
Fine Scale ◽  
Habitat Loss And Fragmentation

JENIS BURUNG DI KAMPUS UNIVERSITAS TANJUNGPURA

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Sutarto Kusuma Indra ◽  
Kustiati Kustiati ◽  
Rafdinal Rafdinal
Keyword(s):  
Habitat Loss ◽  
Human Life ◽  
Natural Habitat ◽  
Bird Species ◽  
Residential Land ◽  
Encounter Rates ◽  
Passer Montanus ◽  
Quality Degradation

Quality degradation, modification, and habitat loss are significant threats to bird species. The natural habitat of birds has been modified into residential land and facilities to meet the needs of human life as happened at Tanjungpura University. This study aims to determine of birds species at Tanjungpura University. Observations were carried out from January to March 2019. The method used in collecting the data from bird was “Encounter rates” which was conducted in the morning starting at 6 – 9 am and at 3 - 6 pm. The data obtained were analyzed with the formula of simple abundance scale and frequency of attendance. The birds found at Universitas Tanjungpura are 28 species classified into 23 genera, 17 families, and seven orders. Birds found to have an abundance order scale are classified into abundant, general, frequent and, unusual categories. Birds included in the abundant category are Collocalia fuciphaga and Passer montanus. The types of bird foods at Tanjungpura University consist of frugivore, insectivore, granivore, herbivore, carnivore, piscivore, omnivore, molluscivore, and nectarivore. The value of attendance frequency have range between 10-100%. The bird species with highest frequency of attendance’s value is Passer montanus, Pycnonotus aurigaster, Pycnonotus goiavier, Collocalia fuciphaga, and Anthreptes malacensis.

Die Brutvogelfauna eines Nadelwaldes der nördlichen Voralpen nach dem Sturm Lothar

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.

PENGEMBANGAN MEDIA BIG BOOK UNTUK MENINGKATKAN HASIL BELAJAR PECAHAN SENILAI SISWA SD

2018 ◽  
Vol 16 (1) ◽  
pp. 67-76
Author(s):  
Disyacitta Neolia Firdana ◽  
Trimurtini Trimurtini
Keyword(s):  
Learning Outcomes ◽  
Large Scale ◽  
Fourth Grade ◽  
Learning Activities ◽  
Equivalent Fractions ◽  
Fourth Grade Students ◽  
Teacher Needs ◽  
The Media ◽  
Test Result ◽  
Better Than

This research aimed to determine the properness and effectiveness of the big book media on learning equivalent fractions of fourth grade students. The method of research is Research and Development  (R&D). This study was conducted in fourth grade of SDN Karanganyar 02 Kota Semarang. Data sources from media validation, material validation, learning outcomes, and teacher and students responses on developed media. Pre-experimental research design with one group pretest-posttest design. Big book developed consist of equivalent fractions material, students learning activities sheets with rectangle and circle shape pictures, and questions about equivalent fractions. Big book was developed based on students and teacher needs. This big book fulfill the media validity of 3,75 with very good criteria and scored 3 by material experts with good criteria. In large-scale trial, the result of students posttest have learning outcomes completness 82,14%. The result of N-gain calculation with result 0,55 indicates the criterion “medium”. The t-test result 9,6320 > 2,0484 which means the average of posttest outcomes is better than the average of pretest outcomes. Based on that data, this study has produced big book media which proper and effective as a media of learning equivalent fractions of fourth grade elementary school.

scholarly journals Prevalence and genetic diversity of avian haemosporidian parasites in wild bird species of the order Columbiformes

2021 ◽  
Author(s):  
Yvonne R. Schumm ◽  
Dimitris Bakaloudis ◽  
Christos Barboutis ◽  
Jacopo G. Cecere ◽  
Cyril Eraud ◽  
...  
Keyword(s):  
Host Species ◽  
Large Scale ◽  
Phylogenetic Reconstruction ◽  
Bird Species ◽  
Avian Species ◽  
Blood Parasites ◽  
Migration Strategy ◽  
Haemosporidian Parasites ◽  
Multiplex Pcr Assay ◽  
And Migration

AbstractDiseases can play a role in species decline. Among them, haemosporidian parasites, vector-transmitted protozoan parasites, are known to constitute a risk for different avian species. However, the magnitude of haemosporidian infection in wild columbiform birds, including strongly decreasing European turtle doves, is largely unknown. We examined the prevalence and diversity of haemosporidian parasites Plasmodium, Leucocytozoon and subgenera Haemoproteus and Parahaemoproteus in six species of the order Columbiformes during breeding season and migration by applying nested PCR, one-step multiplex PCR assay and microscopy. We detected infections in 109 of the 259 screened individuals (42%), including 15 distinct haemosporidian mitochondrial cytochrome b lineages, representing five H. (Haemoproteus), two H. (Parahaemoproteus), five Leucocytozoon and three Plasmodium lineages. Five of these lineages have never been described before. We discriminated between single and mixed infections and determined host species-specific prevalence for each parasite genus. Observed differences among sampled host species are discussed with reference to behavioural characteristics, including nesting and migration strategy. Our results support previous suggestions that migratory birds have a higher prevalence and diversity of blood parasites than resident or short-distance migratory species. A phylogenetic reconstruction provided evidence for H. (Haemoproteus) as well as H. (Parahaemoproteus) infections in columbiform birds. Based on microscopic examination, we quantified parasitemia, indicating the probability of negative effects on the host. This study provides a large-scale baseline description of haemosporidian infections of wild birds belonging to the order Columbiformes sampled in the northern hemisphere. The results enable the monitoring of future changes in parasite transmission areas, distribution and diversity associated with global change, posing a potential risk for declining avian species as the European turtle dove.

scholarly journals Assessment of Numerical Methods for Plunging Breaking Wave Predictions

2021 ◽  
Vol 9 (3) ◽  
pp. 264
Author(s):  
Shanti Bhushan ◽  
Oumnia El Fajri ◽  
Graham Hubbard ◽  
Bradley Chambers ◽  
Christopher Kees
Keyword(s):  
Solitary Wave ◽  
Wave Breaking ◽  
Large Scale ◽  
Turbulence Models ◽  
Navier Stokes ◽  
Wave Crest ◽  
Breaking Wave ◽  
Rans Turbulence Models ◽  
Run Up ◽  
Better Than

This study evaluates the capability of Navier–Stokes solvers in predicting forward and backward plunging breaking, including assessment of the effect of grid resolution, turbulence model, and VoF, CLSVoF interface models on predictions. For this purpose, 2D simulations are performed for four test cases: dam break, solitary wave run up on a slope, flow over a submerged bump, and solitary wave over a submerged rectangular obstacle. Plunging wave breaking involves high wave crest, plunger formation, and splash up, followed by second plunger, and chaotic water motions. Coarser grids reasonably predict the wave breaking features, but finer grids are required for accurate prediction of the splash up events. However, instabilities are triggered at the air–water interface (primarily for the air flow) on very fine grids, which induces surface peel-off or kinks and roll-up of the plunger tips. Reynolds averaged Navier–Stokes (RANS) turbulence models result in high eddy-viscosity in the air–water region which decays the fluid momentum and adversely affects the predictions. Both VoF and CLSVoF methods predict the large-scale plunging breaking characteristics well; however, they vary in the prediction of the finer details. The CLSVoF solver predicts the splash-up event and secondary plunger better than the VoF solver; however, the latter predicts the plunger shape better than the former for the solitary wave run-up on a slope case.

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