Migration pattern and wintering population of the Eurasian marsh harrier (Circus aeruginosus) in the Central Marshes, a wetland of international importance in southern Iraq

Abstract

There is scarce information on the migration patterns and population size of the Eurasian marsh harrier (Circus aeruginosus) in Iraq in general and in the southern Mesopotamian wetlands in particular. From February 2018–April 2019, a total of 11 field expeditions were conducted in the Central Marshes (219,700 ha), one of the major Mesopotamian wetlands and Iraq’s National Park, a RAMSAR and UNESCO site. Two of the field survey objectives were to determine the spatial and temporal distribution and estimate the population size of the migratory/wintering Eurasian marsh harrier in the Central Marshes. Distance sampling on three line-transects covering a study plot of 40,000 ha was conducted. Among other wintering Circus harriers, the Eurasian marsh harrier was the most abundant species with a total of 93 individuals recorded. The estimated species densities were 0.0042–0.035 individuals/ha, and the estimated size of the Eurasian marsh harrier migratory population in the Central Marshes was 922.7–7,689.5 individuals. Moreover, the migration phenology and breeding status of the Eurasian marsh harrier in the Central Marshes were investigated. Our efforts did not confirm the breeding of this species during recent years, or since the inundation of the Mesopotamian wetlands in 2003. Furthermore, hunting and trapping were identified as major threats affecting the species which need urgent conservation action.

Current Conservation Status of the Migratory Western Marsh Harrier Throughout the Unesco Site in Al-Chibayish Marsh, South of Iraq

“…We also accurately measured the distance to the species using a digital range finder. It's worth noting that the more accurate the distance measurements, the more accurate the estimation of density (Sutherland, 2006) Data Analysis: In each survey, Marsh Harrier density was estimated using distance sampling based on precise distance analysis as a simple estimate of density using line transect data (Sutherland, 2006;Al-Sheikhly and Al-Azawi, 2019a). The estimated density (D ^) of Marsh Harrier was extracted by applying the equation below:…”

“…The estimated Marsh Harrier density was then extrapolated on the total area of the Central Marshes to offer the most accurate population estimate/extrapolation for the Marsh Harrier observed (Fazaa et al, 2015;Al-Sheikhly and Al-Azawi, 2019a). Extrapolation was achieved via the multiplication of the species estimation of density from our survey by the Central Marshes' overall area (219,700 ha).…”

“…Nevertheless, high numbers of predating birds are at risk of declining in numbers, and some are even facing extinction (Gousy-Leblanc During spring and autumn, the major flyways are used by large numbers of migratory raptors, avoiding high mountain chains and large bodies of water and becoming concentrated in large numbers at a small number of bottleneck sites all over the Red Sea, Mediterranean Sea, and Black Sea (Verhelst et al, 2011). To reach the Middle East during autumn, these birds that migrate from the eastern part of the western Palearctic use two main flyways: one that follows each side of the northern Caspian Sea and the Black Sea regions, avoiding the northern Red Sea and the eastern Mediterranean Sea, and one that moves across Palestine, taking the Dead Sea-Kfar Kasem-Eliat-Suez and North Negev pathways, reaching Sinai (Fülöp et al, 2018;Al-Sheikhly and Al-Azawi, 2019a). The second major route follows the southeastern part of the Caspian Sea, which crosses the north Arabian Peninsula and the Arabian Gulf through the Hormuz Straits and the southern Red Sea through the Bab El-Mandeb Straits between Djibouti and Yemen (Panuccio et al, 2018).…”