Wetland Birds of the Hydrographic Network of Altyn Asyr

Author(s):  
Eldar A. Rustamov ◽  
Anna V. Belousova
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuanxing Ye ◽  
Canshi Hu ◽  
Yiting Jiang ◽  
Geoffrey W. H. Davison ◽  
Changqing Ding

Abstract Background Interspecific competition is known to be strongest between those species that are both closely related and sympatric. Egrets are colonially nesting wetland birds that often overlap and can therefore be expected to compete in roosting and nesting habitat as well as in diet. According to the niche partitioning hypothesis, it is to be expected that these similar species would show differentiation in at least one of the main niche dimensions to reduce competition. We tested niche partitioning between the colonially nesting Little Egret (Egretta garzetta) and Cattle Egret (Bubulcus ibis) in temporal, spatial and trophic dimensions. Methods Field study was conducted in three mixed egret colonies in Yangxian County, southwest Shaanxi Province, central China. For each nest colony we recorded its spatial location, the height of nesting trees and of nests, the height of roosting trees and of roosting individuals within the trees. We determined the first egg-laying and first hatching dates of the two species. Craw dissection of storm-killed egret nestlings was used to measure the diet. Six transects were surveyed to study foraging habitat selection. Results We found that hatching time of Little Egrets peaked earlier (by about 1 month) than that of Cattle Egrets. Cattle Egrets nested and roosted higher than Little Egrets. The foraging habitats used by Little Egrets were dominated by river banks (73.49%), followed by paddy fields (13.25%) and reservoirs (10.84%), whereas Cattle Egret foraging sites were characterized by grasslands (44.44%), paddy fields (33.33%) and river banks (22.22%). Little Egrets consumed more fishes (65.66%) and Odonata larvae (13.69%) than Cattle Egrets, while Cattle Egrets were found feeding mainly on Coleoptera (29.69%) and Orthoptera (23.29%). Little Egrets preyed on larger mean biomasses of food items than Cattle Egrets. Conclusions Our results confirm the niche partitioning hypothesis as a mechanism for coexistence among ecologically similar species. In two coexisting egret species, niche partitioning is multidimensional, such that the two coexistent species occupy differing ecological space based on all three temporal, spatial and trophic niche dimensions.


1992 ◽  
Vol 34 (4) ◽  
pp. 285-295 ◽  
Author(s):  
Neil D. Burgess ◽  
Graham J.M. Hirons
Keyword(s):  

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Rubayet Elahi ◽  
Ausraful Islam ◽  
Mohammad Sharif Hossain ◽  
Khaja Mohiuddin ◽  
Andrea Mikolon ◽  
...  

The parasites of generaHaemoproteus, Plasmodium,andLeucocytozoonare well-known avian haematozoa and can cause declined productivity and high mortality in wild birds. The objective of the study was to record the prevalence of haematozoan parasites in a wide range of wetland birds in Bangladesh. Six species ofHaemoproteus, seven species ofPlasmodium, one unidentified species ofLeucocytozoon, and one unidentified microfilaria of the genusParonchocercawere found. Data on the morphology, size, hosts, prevalence, and infection intensity of the parasites are provided. The overall prevalence among the birds was 29.5% (95 out of 322 birds). Of those, 13.2% (42 of 319) of birds were infected withHaemoproteusspp., 15.1% withPlasmodiumspp. (48 of 319) and 0.6% withLeucocytozoonspp. (2 of 319). Two birds were positive for bothHaemoproteussp. andPlasmodiumsp. A single resident bird,Ardeola grayii, was found positive for an unidentified microfilaria. Prevalence of infection varied significantly among different bird families. Wild birds of Bangladesh carry several types of haematozoan parasites. Further investigation with a larger sample size is necessary to estimate more accurately the prevalence of haematozoan parasites among wild birds as well as domestic ducks for better understanding of the disease ecology.


2017 ◽  
Vol 9 (1) ◽  
pp. 9700 ◽  
Author(s):  
Carol Inskipp ◽  
Hem Sagar Baral ◽  
Tim Inskipp ◽  
Ambika Prasad Khatiwada ◽  
Monsoon Pokharel Khatiwada ◽  
...  

The main objectives of the Nepal National Bird Red Data Book were to provide comprehensive and up-to-date accounts of all the bird species found in Nepal, assess their status applying the IUCN Guidelines at Regional Levels, identify threats to all bird species and recommend the most practical measures for their conservation.  It is hoped that the Bird RDB will help Nepal achieve the Convention on Biological Diversity target of preventing the extinction of known threatened species and improving their conservation status.  As population changes of Nepal’s birds have been studied for only a few species, assessments of species’ national status were mainly made by assessing changes in distribution.  Species distribution maps were produced for all of Nepal’s bird species except vagrants and compared to maps that were produced in 1991 using the same mapping system.  Of the 878 bird species recorded, 168 species (19%) were assessed as nationally threatened. These comprise 68 (40%) Critically Endangered species, 38 (23%) Endangered species and 62 (37%) Vulnerable species.  A total of 62 species was considered Near Threatened and 22 species Data Deficient.  Over 55% of the threatened birds are lowland grassland specialists, 25% are wetland birds and 24% tropical and sub-tropical broadleaved forest birds.  Larger birds appear to be more threatened than smaller birds with 98 (25%) non-passerine species threatened and 67 (14%) passerine species.  Habitat loss, degradation and fragmentation are the most important threats.  Other threats include chemical poisoning, over-exploitation, climate change, hydropower, invasive species, intensification of agriculture, disturbance, and limited conservation measures and research.  Measures to address these threats are described.  It was also concluded that re-assessments of the status of certain bird groups carried out every five years and the setting up of a national online system for storing and reporting bird sightings would be useful.


Author(s):  
A.I. Petelko ◽  

Reclamation of land on community land funds and the hydrographic network contributes to the most effective means of protecting the soil from water erosion. However, the condition, growth, and productivity of the protective forest stands themselves depend on the species composition. Many years of studies have clearly shown that not all tree species and shrubs can successfully grow on washed soils. Extensive scientific material provides a description of the growth and current status of the studied species, a detailed taxation description of the forest plantations. Of particular value are those species that can grow on eroded lands and protect the soil from erosion.


2017 ◽  
Vol 5 (2) ◽  
pp. 37-48
Author(s):  
Alicja Pradela ◽  
Andrzej Zygmuniak

Abstract The traditions related to mining activities in the Silesia-Cracow area go back to the 11th century when lead, silver, and iron ores were exploited from open pit mines. For centuries, the growth in ore exploitation was an incentive for the development of other industries (hard coal mining, steelmaking). This, in consequence, resulted in progressive urbanization. The areas analyzed are of highly transformed character, mainly because of mining activities. These changes are especially seen in relation to the aquatic environment since this component is exposed to heavy modifications due to the mining processes. Hence the study was carried out in order to determine the quantitative changes in the surface hydrographic network. It was found, that of the 62 main watercourses (existing during the whole analyzed period) 25 changed only slightly in terms of their length, 20 shortened by a few hundred meters and 17 lengthened. In the case of the aggregated length of the tributaries, the value increased for the 41 main watercourses, for 10 of them it was constant and was reduced slightly for a further 11. The areas where the length of the watercourses increased and the drainage density grew were found to be as well those where the total area of wetlands decreased. The element of the hydrographic network which was affected by the most changes was the water bodies. During the analyzed period of over 200 years, their number increased from 154 to 1413.


Check List ◽  
2009 ◽  
Vol 5 (2) ◽  
pp. 154 ◽  
Author(s):  
Renildo Ribeiro de Oliveira ◽  
Marcelo Salles Rocha ◽  
Maeda Batista dos Anjos ◽  
Jansen Zuanon ◽  
Lúcia H. Rapp Py-Daniel

This study was conducted in an Amazonas state conservation unit, the Catuá-Ipixuna Extractive Reserve (Catuá-Ipixuna RESEX). The main purpose was to provide an ichthyological survey of its small streams, all them tributaries of the Solimões River. Nine small streams (up to 4 m width and 1 m depth) were sampled in September 2006. A total of 1,525 specimens were captured, belonging to 78 species, 24 families and eight orders. Eight species had higher abundances and represented altogether 61.4 % of all collected specimens (Hemigrammus belotii, Microphilypnus amazonicus, Physopyxis ananas, Apistogramma agassizii, Elachocharax pulcher, Apistogramma cf. cruzi, Gladioglanis conquistador and Copella nigrofasciata). Based on the high number of singletons and doubletons present in our samples, as well as the estimated number of species for those streams (106 spp.), we believe that the total fish species richness present in the Catuá-Ipixuna Extractive Reserve may be considerably higher than indicated by our samples. This seems especially true when considering the dimensions of the Catuá-Ipixuna RESEX and the dense hydrographic network present in the area.


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