Farhad Hosseini Tayefeh; Saber Ghasemi; Mona Izadian; Seyyed Ghasem Ghorbanzadeh
Abstract
Background and purpose: Anatidae family is considered as a biological indicator of wetlands due to their migratory behavior, wide distribution and high population density. Three wetlands of the Bakhtegan basin, namely Bakhtegan, Tashk and Kamjan in Fars province, are important habitats for Anatidae in ...
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Background and purpose: Anatidae family is considered as a biological indicator of wetlands due to their migratory behavior, wide distribution and high population density. Three wetlands of the Bakhtegan basin, namely Bakhtegan, Tashk and Kamjan in Fars province, are important habitats for Anatidae in the central plateau of Iran. The purpose of this research was to evaluate fluctuations in the wintering population of the Anatidae family in wetlands of the Bakhtegan basin in a long-term period of 52 years from 1967 to 2018. Materials and methods: Data on the population and diversity of waterbirds were obtained from a 52-year census data of the Department of the Environmental of Iran. Results of field studies in 2019 were also used to investigate their current habitat condition, data validation and monitoring of Anatidae populations. Of 21 Anatidae species recorded in Iran, nine species with a population of more than 50 individuals per year and observed at least 20 years, were investigated along with the Vulnerable species (VU) of Common Pochard Aythya ferina. Annual changes in the total population of waterbirds, the number of species in each year, the proportion of Anatidae in the population and the diversity of waterbirds in Bakhtegan wetlands and the statistical trend of population changes of species were analyzed. Trend of long-term changes in the population of Anatidae species were calculated using the RTRIM statistical package and Multi-species Indicators (MSI).Results and discussion: A total of 21 of Anatidae species, including Endangered species (EN) of White-headed Duck Oxyura leucocephala, Marbled Duck Marmaronetta angustirostris (VU) and Common Pochard (VU) and Near Threatened species (NT) of Ferruginous Duck Aythya nyroca were identified in the wetlands of Bakhtegan basin. The average population of Anatidae in a 31-year period (1988–2008) was more than 169,000 individuals, but in the last ten years (2009–2018), it decreased to 6,623 individuals. The highest number of total population was in 1995 with 632,510 individuals and the lowest with 1,135 individuals in 2016. The highest and lowest number of species were in 2000 and 2010 with 13 and 3 species, respectively. The statistical trend of the population changes showed that the Greylag Goose Anser anser faced a steep decline in the long-term with a slope of -21%, the Shelduck Tadorna tadorna with a steep decline (-8.4%), the Ruddy Shelduck Tadorna ferruginea with a stable population and zero percent, the Mallard Anas platyrhynchos and the Eurasian Teal Anas crecca with a steep decline and slope of -12.1% and -6.5%, respectively. Trend of changes in the last ten years for the Greylag Goose was stable (0.1%), Shelduck with an uncertain state (4.8%), Ruddy Shelduck and Mallard with a decrease and a slop of -3.8% and -9.4%, respectively, and Eurasian Teal with a strong increase (48.9%). The results indicate that Bakhtegan wetlands had a high proportion of waterbirds during the 1990s to the early 2000s, but it has lost its position in the last 15 years. Bakhtegan wetlands used to be the breeding habitat for Marbled Ducks, but there have been no reports of its breeding in recent years.The reduction of water level, drying wet areas and changes in habitat variables have been the most important factors in reduction of the population and diversity of Anatide species. Conclusion: The Anatidae family has more than 30% of species diversity and more than 53% of the total population of waterbirds in Bakhtegan wetlands. Currently, it is possible for birds to spend the winter in only a small part of Tashk wetland in the area of Gamban spring. Reconstruction, restoration and making continuous and effective protection of the wetland chain of Bakhtegan Basin requires allocating the required water from diverse water sources for its biological sustainability. In the case of increasing the level and depth of these water areas, the possibility of increasing the population and diversity of diving ducks and Mergus species is expected. Due to the importance of the participation of stakeholders in the protection and restoration of wetlands, it is necessary to take action regarding the allocation of biological water rights and participatory protection of wetlands according to the social, economic, cultural and political conditions.
Farhad Hosseini Tayefeh; Mona Izadian; Abbas Ashoori; leyla Jolaee; Elham Ebrahimi
Abstract
Introduction: Using of waterbirds (waterfowl and waders) census data is common to calculate the size and trend of population changes. Besides, it is important as an indicator of wetlands’ ecological changes in biodiversity conservation. Fars province’s wetlands are one of the most diverse ...
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Introduction: Using of waterbirds (waterfowl and waders) census data is common to calculate the size and trend of population changes. Besides, it is important as an indicator of wetlands’ ecological changes in biodiversity conservation. Fars province’s wetlands are one of the most diverse aquatic habitats in Iran where have been severely damaged in recent years due to reduced water levels and habitat changes and consequently, these international wetlands are categorized in the list of Montero as a threatened wetland. In this study, trends of total Waterbirds population changes in Fars province and their main wetlands, including Bakhtegan Basin (Kajjan, Tashk, and Bakhtegan), Parishan and Arjan Plain international wetlands, next to important wetlands of Kaftar, Maharloo and Droudzan Dam Lake have been investigated. Material and methods: The results of the migratory Waterbirds’ census in Fars province had been obtained from the Department of Environment for about thirty years (1988–2018). Though the population census has been conducted in Fars province since 1967, during the years 1967 to 1987, the census was confined to swans, geese, ducks, and coots, other waterbirds have been added to the bird census since 1988.Data had been analyzed in a long-term period (31-years, 1988-2018) and a short-term period (10-year, 2009-2018) by using RTRIM statistical package. This package has been extracted from Trends & Indices for Monitoring Data (TRIM) in R software. Results and discussion: About 14% of the population and 67% of Iran's waterbirds (116 out of 174 species of Iran) have been related to Fars province, in 31 years ago. The results have been shown a sharp decline in the total population of migratory waterbirds in Fars province with -10.9% slope (0.891 ± 0.0004) per year and also a sharp decline in population with -11% slope for a 10-year period (0.890±0.0001). Only the Maharloo wetlands in the long-term and the Drudzen Dam Lake in the Short-term had a stable population trend, while in other wetlands the trend of decreasing population was moderate to steep. The highest long-term population decline was observed in Parishan wetlands and Arjan plain with -13.9% and -10.1%, respectively. In the short-term, the Parishan wetland had the highest population decline of -10% (0.861 ±0.0001) per year. The highest number of species was observed in the 90s and also in 2004-2009, after this period the species richness of these wetlands decreased. as far as the result shows, the proportion of Bakhtegan and Parishan’s waterbird population was varied from 10% to 88% of the total Fars province’s population. Also, the lowest proportion of the waterbird’s population in these two wetlands was recorded in the last ten years. It seems that drying up of aquatic zones and land-use change were among the most important factors affecting the reduction of population and species richness of waterbirds. As a matter of fact, these wetlands do not have the 5 international criteria of Ramsar wetlands based on the status of the waterbird population. Therefore, need to be prioritized and effective restoration and protection of them in environmental protection programs. Conclusion: In recent years, habitat changes due to aquatic changes and anthropogenic factors have reduced the quality of wetland habitats in Fars province and drastic changes in waterbird populations. Providing the environmental sustainability needed for ecological sustainability, establishing an integrated ecosystem management system, implementing comprehensive wetland management programs, and population monitoring are the most important restoration strategies for the studied wetlands. The results of this study can be used in the management of wetlands ecosystems, preparation and implementation of the restoration plan and also a calculation of damages to wetlands in Fars province.
