Number Of Waterbird Species Research Articles

Coastal wetland vegetation features and digital Change Detection Mapping based on remotely sensed imagery: El-Burullus Lake, Egypt

El-Burullus Lake is one of the four Egyptian Ramsar sites that constitute internationally important wetlands as they contain a rich biodiversity and have a large number of water bird species. But the valuable resources in El-Burullus Lake and its surrounding area have faced various threats to wetlands over recent decades. This study was carried out to evaluate the dynamics of land cover change using three change scenes of recent and past satellite data from 1990 to 2019. The study utilized ArcGIS10.7, ERDAS Imagine 14, Landsat TM (1990, 1999, and 2010), Landsat OLI-TIRS (2019) to analyze the land-use/land-cover (LULC) of El-Burullus wetland. Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) were employed to assess the change scenario of the area. Results indicated that vegetated land has increased significantly with a concomitant shrinkage in the water body and open soil during the study period. Approximately 53 km2 (7.0%) of water body and 8.7 km2 (1.3%) of open soil were lost, while vegetation areas expanded to approximately 29.9 km2 (7.4%). Factors that underpin the observed changes in the area are; reclamation projects and fish-farms which are creating the danger of drying up of the southern coastal parts of the lake, as well as spreading of reed beds (mainly: Phragmites australis) that covers about 20% of El-Burullus lake which led to dry up the lake parts. Therefore, the study suggests the need for urgent attention on conservation of remaining wetland resources for sustainable utilization for the next generation.

Comparison of waterbird species composition and habitat characteristics of two different wetlands of Malaysia

Waterbird species composition and habitat characteristics at two ecologically different wetlands (Paya Indah and Putrajaya) were compared in order to determine the habitat suitability of each particular habitat for waterbird species. A total of 30 waterbird species representing 10 families were recorded through direct observation in both wetland habitats (26 waterbird species in Paya Indah and 22 species in Putrajaya wetland habitats). Out of 30 waterbird species, 17 species were commonly recorded from both habitats, 4 species were absent in Paya Indah and 8 species in Putrajaya. Ardeidae was the dominant family based on the number species (11 waterbird species) while Charadriidae, Ciconiidae, Jacanidae, Pelicanidae and Podicipedidae were the rarest families (only one species was recorded) in both wetland habitats. This indicated that both wetland habitats may vary in waterbird species composition habitat characteristics, that is, a total of 34 aquatic plant species (21 species in Paya Indah and 18 species in Putrajaya wetland) belonging to 14 families were sampled during study period. Five plant species, namely, Water Chestnut– Eleocharis dulcis, Twig Rush– Lepironia articulate, Blue Lotus– Nymphaea nouchali, Common Reed– Phragmites karaka and Cattail– Typha angustifolia were commonly recorded from both habitats. However, 13 aquatic plant species were absent in Paya Indah and 16 species in Putrajaya wetland. The findings of this study, revealed that Paya Indah wetland is rich in waterbird species composition and habitat characteristics as compared to Putrajaya wetland habitat. This might be due to the richness and diversity of aquatic vegetation composition, occurrence of suitable foraging and breeding sites that had attracted the highest number of waterbird species to utilize the Paya Indah wetland habitat. Key words: Waterbirds, aquatic vegetation, Paya Indah, wetland.

A preliminary assessment on the role of abandoned shrimp farms on supporting waterbirds in Pichavaram mangrove, Tamilnadu, Southern India

Asian wetlands are pivotal habitats for numerous globally declining migratory and resident waterbird species. Ironically 80% of the wetlands in East and South East Asia are classified as threatened, with 50% under grave threat. In particular the mangrove wetlands are under serious threat due to large scale conversion for commercial shrimp ponds and sea level rise. So, the impoverishment of natural wetlands has forced waterbirds to find alternative habitats. On the other hand, some recent studies have highlighted the potential role of anthropogenic, artificial and restored habitats such as coastal grazing marshes, salinas and rice fields to be good habitats for waterbirds. The present study was mainly designed to investigate the role of abandoned shrimp ponds near the mangroves supporting the migratory and resident waterbirds in the Kodiyampalayam area of Pichavaram mangroves. The results show that the abandoned aqua ponds support 26 species of waterbirds. Among them, 16 were migrant and three were in the near threatened (NT) category of IUCN. Suggestions were made in order to improve the habitat to attract more number of waterbird species in the near future.

Hanöbukten, an important wintering area for waterbirds in South Sweden

Hanöbukten in SE Sweden (including Blekinge archipelago) is an important wintering and staging area for a number of waterbird species. The inshore parts have been covered by counts from the shore during the International Waterbird Counts (IWC) since 1969. In the present study we analyze these counts for the period 1969–2014. When the counts started the total number of wintering waterbirds varied between 20,000 and 40,000 per year. However, from the early 1990s the number doubled, reaching 60,000 to 80,000 birds per year. All species with the exception of the Long-tailed Duck Clangula hyemalis showed similar increase. The area had a high proportion of the Swedish wintering population of Pochard Aythya ferina and Smew Mergellus albellus. Large numbers of Tufted Duck Aythya fuligula also wintered in the area, and some parts of the archipelago had internationally important concentrations of Tufted Duck and Smew. The increase in numbers in the study area showed the same pattern as in all Sweden and was most probably a result of milder winters in recent years.

Whole‐community facilitation by beaver: ecosystem engineer increases waterbird diversity

ABSTRACTWetlands are rich in biodiversity, but globally threatened. After a long period of regional extirpation, beavers have recently returned to many European areas and are now restoring wetlands. The beaver is remarkable regarding the large impacts it has not only on individual species but on entire communities and ecosystems. In fact, beavers are referred to as ‘ecosystem engineers’.The facilitative effect of the beaver Castor canadensis on a waterbird community of seven species of waders and ducks in boreal ponds was studied by using the before–after control–impact method (BACI) and analysing the effect of the duration of flooding. The before–after setting could be used since beavers had caused disturbance by flooding several forest ponds during the course of this long‐term study (1988–2009). The study took place in southern Finland, where waterbirds were surveyed four times during the breeding season.The number of waterbird species per pond per year was significantly higher during beaver inundation than before beaver activity, as was the waterbird abundance per survey. Changes were negligible in the controls. The numbers of all seven species increased during flooding, although the increase was significant in only three species. Common teal Anas crecca and green sandpiper Tringa ochropus showed the most positive numerical response to flooding. Mallard Anas platyrhynchos and wigeon Anas penelope were new species entering the duck guild in the flooded wetlands. The beneficial effect of the flood lasted the whole period of inundation, although the most substantial increase in species number appeared during the first two years of flooding.The beaver acted as a whole‐community facilitator for waterbirds. It was inferred from previous studies that this was done by modifying the habitat to make it more productive and structurally favourable. It is concluded that favouring beavers is a worthwhile tool in restoring wetlands to promote waterbird communities. Copyright © 2014 John Wiley & Sons, Ltd.

都市部河川緑地における越冬期の鳥類相に影響を及ぼす要因

In order to suggest desirable openspaces in terms of biodiversity in urban riparian, it was studied that relationship between wintering avifauna and habitat structures and landuse around study sites. 24 study sites were located on 2 urban riparian areas in northwest part of Chiba Prefecture, Japan. As a result, significant negative correlations of the number of water bird species with the slant of water edge were found. Considering avifauna composition, the 24 sites were classified into 2 types by TWINSPAN. Canonical discriminant analysis indicated that the area of water, area of the artificial structures can interpret the classifications by TWINSPAN. The results showed that the waterside such as a sharp slant has a negative influence on the number of water bird species and the area of artificial structures affected some birds. This study revealed the importance of the area of waters and the waterside form for water species. In planning the form of rivers regarding the preservation of avifauna, it is important to consider the riparian environment, such as vegetation and the structure of the water's edge. In addition, it is necessary to pay attention to the relationship between riparian areas and these surroundings.

Conservation implications of flooding rice fields on winter waterbird communities

The effects of flooding harvested rice fields on waterbird communities were studied during winter. Variation in the number of waterbird species, overall densities of all waterbirds, wading birds, waterfowl, and shorebirds, and a measure of conservation value that weighted species according to their relative abundance and population trends were examined. Each variable was tested for differences among: (a) flooded and unflooded fields; (b) flooded fields that received different rice straw manipulations; and (c) fields with different water depths. Flooded fields were used by waterbirds more than unflooded fields according to most criteria, although wading bird densities did not differ between flooded and unflooded fields. In terms of conservation value, flooded fields contributed considerably more to waterbird conservation than unflooded fields. The number of waterbird species, total waterbird density, and the density of wading birds differed significantly among straw management treatments, though in different ways. Water depth significantly affected all measures, but in all cases most of the variation went unexplained. Bird densities were explained best by asymptotic relationships, with shorebird densities greatest in shallow water and waterfowl and wading bird densities greatest in deeper conditions. Waterbird richness and conservation value both were greatest at depths of 10–15 cm. Intentionally flooding fields during winter significantly affected numerous aspects of the waterbird community. The method of flooding also influenced the waterbird community, although these effects often were small.