Podoces
Volume:5 Issue: 2, 2010

The Western Reef Heron Egretta gularis is a native breeding waterbird along thesouth coast of Iran and on offshore islands. It has been found nesting on trees, shrubs and bushes at 13 sites consisting of nine islands and four tidal areas. The total breedingpopulation was estimated at about 400 pairs during the 2006–2010 period. The largestbreeding colony of this heron, with at least 180 pairs, was in the mangrove forests of HaraProtected Area (Biosphere Reserve) in 2009. The main threats to the breeding population of Western Reef Herons in this site were habitat destruction and invasive species, especially the Black Rat Rattus rattus. Further studies on the status of the breeding populations and threats to the species will be useful for monitoring ecological changes in coastal and wetland ecosystems in southern Iran. According to the DOE mid-winter waterbird census data, the average wintering population of the species in southern Iran was 1,168 individuals (min. 97 and max. 2,125 individuals) during the period 2000–2009.

A study of the breeding performance of the Western Reef Heron Egretta gulariswas carried out on Nakhiloo Island in the Persian Gulf from March to September 2008. Atotal of 92 pairs nested on the island in four colonies. The breeding success during theincubation, nestling and post-nestling stages was 62.1%, 46.4% and 39.2%, respectively.Overall breeding success (the proportion of eggs laid that were successfully reared tofledging) was 39.2%, for 60 fledglings (N=153 eggs). Predation on eggs by Black RatsRattus rattus, high temperatures and desertion due to unknown reasons were the mostimportant causes of breeding failure. The average weight of the chicks was 22.19±0.61 g at hatching and 590±10 g at fledging.

This study was conducted at five sites on Kharg Island in the Persian Gulf:Ershad Guest House, Falat-e Ghare, Melli Bank, Sadaf cinema and the petrochemical site.Estimates of the population size of the House Crow Corvus splendens were made on 10September 2009, 20 December 2009 and 10 January 2010. The breeding population wasestimated on 22 July 2010. The population of House Crows was 5,212 individuals on 10September, 4,950 individuals on 20 December and 5,500 individuals on 10 January(average 5,220 individuals). The breeding population was estimated as 1,451 pairs based on the number of active nests, and a total of 1,871 old nests were also located. During the summer, autumn and winter seasons, the non-breeding House Crows roosted on 32 trees of Ficus bengalensis, 62 Eucalyptus, and one Ziziphus aucheri. The non-breeding population was more than the breeding population (5,220 non-breeding individuals, and 1,451 breeding pairs). Nests of the House Crow were composed mainly of two types of material, wood and pieces of discarded wire. The clutch size was 3–5, but most of the nests had 4 eggs. The population of this species on Kharg Island increased from about 40 individuals in the early 1970s to 5,500 in 2010.

Diet variations of Barn Owl Tyto alba were determined by the analysis of 3,133regurgitated pellets collected from ten different roost-sites in Madurai District from 2007 to 2009. The overall diet comprised 85.5% small mammals, 2.2% birds, 0.1% reptiles, 0.9% amphibians and 2.4% insects. Among small mammals, Suncus murinus and Rattus rattus were predominant: they comprised 37.2% and 23.0% of the 4,295 prey taken by Barn Owls.The number of prey items per pellet varied from one to 16 with an overall mean of 1.37prey items/pellet. The percentage of small mammal in the pellets varied seasonally from82.5% to 87.5%. Suncus murinus was taken in large numbers from post-monsoon (30.2% to monsoon (51.1%). The occurrence of small mammals in the diet varied from 75.0% to90.4% among the years. The consumption of Suncus murinus showed a decreasing trendfrom 2007 to 2009, whereas the Bandicoota bengalensis, Millardia meltada, Tatera indica,Mus spp. and chiropterans showed an increasing trend. Consumption of Rattus rattus,Tatera indica, Suncus murinus and amphibians were significantly differed among the years.Suncus murinus was chief prey in both rural and urban habitats. Bandicoota bengalensis(18.6%), Millardia meltada (7.8%), Tatera indica (1.8%), Mus spp. (8.5%) and bats (4.2%) were found more frequently in the diet of owls in rural habitat, whereas, Rattus rattus contributed an important fraction of the prey (26.4%) in urban habitat. There were statistical differences in percent frequency of Bandicoota bengalensis, Millardia meltada, Rattus rattus, Tatera indica, amphibians and isopteran insects between the habitats.

The breeding activities of the Great Bustard Otis tarda were studied on the Sootav plainin its main breeding ground in north-western Iran.Of five nests, the first and the last nests were discovered on 7 May with 3 eggs and on 20 May with 2 eggs, respectively. Mean clutch size was 2.8±0.44 and the mean distance to the nearest village and road were 2460± 896.1 and 2615.2±1284 m,respectively. Observations showed that the mean distance of each nest to the nearest nest was also 1334±856.6 m. The breeding population of the Great Bustard on the Sootav plain has declined compared to previous years because of a reduction in thequality of its breeding habitat.

This study was conducted on 16 February 2010 using 10×40 binoculars and scan sampling of 136 individuals of the Greater Flamingo Phoenicopterus roseus. The behaviour of the birds was monitored every 15 minutes from sunrise to sunset in 10 different categories: feeding, drinking, walking, flying, resting, preening, scratching, aggression, showing alarm and loafing. The most important activity was feeding (over 50% of the time in both adult and juvenile individuals). Walking and resting were the two other main activities of the Greater Flamingos during the present study. Overall, the difference in behaviour between adults and juveniles was not statistically significant (P>0.05),but the juveniles spent more time feeding and less time walking and preening than adults, and the differences in time spent feeding and time spent preening were statistically significant (P<0.05).

A survey on mite fauna of bird nests was carried out in Tehran, Golestan and Sistan &Baluchestan provinces in 2008. A total of 18 nests belonging to six bird species, namely Rock Dove Columba livia, House Sparrow Passer domesticus, Eastern Olivaceous Warbler Hippolais (Iduna) pallida, White-eared Bulbul Pycnonotus leucotis, Common Magpie Pica pica and Crested Lark Galerida cristata were collected. Samples were processed by modified Berlese funnel. After extraction, ten mite species from nine families ofthree orders (Sarcoptiformes, Trombidiformes and Mesostigmata) and three suborders (Oribatida, Prostigmata and Monogynaspida) were identified as follow: Acarus siro Linnaeus, 1758, Lepidoglyphus destructor (Schrank, 1781), Suidasia nesbittiHughes, 1948, Acaropsellina sollers (Kuzin, 1940), Cheyletus malaccensis Oudemans, 1903, Cheyletus carnifex Zachvatkin, 1935, Eutogenes foxi Baker, 1949, Tetranychus urticae Koch, 1836, Cenopalpus sp. and Lasioseius penicilliger Berlese, 1916. In this study, the mite fauna were dominated by the species S. nesbitti from the family Suidasiidae and T. urticae from the family Tetranychidae.