LONG-LEGGED WETLAND BIRDS (mostly Waders)

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.

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Creation and management of artificial nesting sites for wetland Birds

Journal of Environmental Management ◽

10.1016/s0301-4797(11)80004-6 ◽

1992 ◽

Vol 34 (4) ◽

pp. 285-295 ◽

Cited By ~ 7

Author(s):

Neil D. Burgess ◽

Graham J.M. Hirons

Keyword(s):

Wetland Birds ◽

Nesting Sites

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Prevalence and Diversity of Avian Haematozoan Parasites in Wetlands of Bangladesh

Journal of Parasitology Research ◽

10.1155/2014/493754 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Rubayet Elahi ◽

Ausraful Islam ◽

Mohammad Sharif Hossain ◽

Khaja Mohiuddin ◽

Andrea Mikolon ◽

...

Keyword(s):

Sample Size ◽

Disease Ecology ◽

Infection Intensity ◽

Wild Birds ◽

Wetland Birds ◽

Domestic Ducks ◽

Wide Range ◽

Unidentified Species ◽

Larger Sample ◽

Resident Bird

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.

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Conservation and Management of Wetland Birds in Rajasthan: Perspectives and Challenges

Faunal Heritage of Rajasthan, India ◽

10.1007/978-3-319-01345-9_10 ◽

2013 ◽

pp. 231-244

Author(s):

Lalitha Vijayan ◽

V. S. Vijayan

Keyword(s):

Wetland Birds ◽

Conservation And Management

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Nepal’s National Red List of Birds

Journal of Threatened Taxa ◽

10.11609/jott.2855.9.1.9700-9722 ◽

2017 ◽

Vol 9 (1) ◽

pp. 9700 ◽

Cited By ~ 2

Author(s):

Carol Inskipp ◽

Hem Sagar Baral ◽

Tim Inskipp ◽

Ambika Prasad Khatiwada ◽

Monsoon Pokharel Khatiwada ◽

...

Keyword(s):

Endangered Species ◽

Biological Diversity ◽

Conservation Status ◽

Bird Species ◽

Convention On Biological Diversity ◽

Wetland Birds ◽

Distribution Maps ◽

Critically Endangered Species ◽

Passerine Species ◽

Over Exploitation

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.

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