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This article belongs to the Special Issue Viral Shedding and Transmission in Zoonotic Diseases., The mosquito-borne flaviviruses USUV and WNV are known to co-circulate in large parts of Europe. Both are a public health concern, and USUV has been the cause of epizootics in both wild and domestic birds, and neurological cases in humans in Europe. Here, we explore the susceptibility of magpies to experimental USUV infection, and how previous exposure to USUV would affect infection with WNV. None of the magpies exposed to USUV showed clinical signs, viremia, or detectable neutralizing antibodies. After challenge with a neurovirulent WNV strain, neither viremia, viral titer of WNV in vascular feathers, nor neutralizing antibody titers of previously USUV-exposed magpies differed significantly with respect to magpies that had not previously been exposed to USUV. However, 75% (6/8) of the USUV-exposed birds survived, while only 22.2% (2/9) of those not previously exposed to USUV survived. WNV antigen labeling by immunohistochemistry in tissues was less evident and more restricted in magpies exposed to USUV prior to challenge with WNV. Our data indicate that previous exposure to USUV partially protects magpies against a lethal challenge with WNV, while it does not prevent viremia and direct transmission, although the mechanism is unclear. These results are relevant for flavivirus ecology and contention., This work was supported by grants RTA2015-009 and E-RTA2017-003-C02 from Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA). more...

Natural hybridization increases a lot phenotypic and genetic diversity and shapes intra-species patterns, which is a subject of phylogeography. We studied mitochondrial and complete genome variation in the bird family Corvidae, genera Corvus, Pica, Cyanopica, Perisoreus and Nucifraga. In the classic case of natural hybridization between carrion and hooded crows in Siberia, we found no decreased fitness of hybrids, but instead positive assortative mating which should restrict hybrid zone width. Several genetic markers were unable to discriminate between pure carrion and hooded crows. Mitochondrial DNA sequences revealed no difference between carrion and hooded crows, but instead two diverged haplogroups within the eastern part of the distribution range of the carrion crow. NGS resulted in a clear pattern of diversification of pure forms and hybrids (by using SNPs), and showed genomic regions of increased variability, the so-called “speciation islands”. Comparing European and Siberian crow hybrid zones, differences in genome regions bearing genes of melanogenesis supposedly under divergent selection were found. Comparative phylogeographic analysis of 10 widely distributed Palearctic species revealed two kinds of patterns: one with a division into two haplogroups, western and eastern, and another one without such a division. These two phylogeographic patterns might be explained by different habitat preferences: mainly open fields for the first group and forests for the second one. One glacial refuge was assigned to the latter group, while west-east group species might have survived in several refuges. One of such species, the Eurasian magpie (Pica pica) has a gap in its range in Transbaikalia, which is currently shrinking before our eyes. The two subspecies divided by this gap differ in phenotype, mtDNA and vocalization. In their young contact zone, some hybridization occurs with small introgression limited by certain post-zygotic isolation. more...

International audience; Gut microbiota are essential for host health and survival, but we are still far from understanding the processes involved in shaping their composition and evolution. Controlled experimental work under lab conditions as well as human studies pointed at environmental factors (i.e., diet) as the main determinant of the microbiota with little evidence of genetic effects, while comparative interspecific studies detected significant phylogenetic effects. Different species, however, also differ in diet, feeding behavior, and environmental characteristics of habitats, all of which also vary interspecifically, and, therefore, can potentially explain most of the detected phylogenetic patterns. Here, we take advantage of the reproductive strategy of avian brood parasites and investigate gut microbiotas (esophageal (food and saliva) and intestinal) of great spotted cuckoo (Clamator glandarius) and magpie (Pica pica) nestlings that grow in the same nests. We also estimated diet received by each nestling and explored its association with gut microbiota characteristics. Although esophageal microbiota of magpies and great spotted cuckoos raised within the same environment (nest) did not vary, the microbiota of cloacal samples showed clear interspecific differences. Moreover, diet of great spotted cuckoo and magpie nestlings explained the microbiota composition of esophageal samples, but not of cloaca samples. These results strongly suggest a genetic component determining the intestinal microbiota of host and parasitic bird species, indicating that interspecific differences in gut morphology and physiology are responsible for such interspecific differences more...

The use of wind turbines for energy generation has complex impacts on ecosystems, especially for flying wildlife. Given the importance of birds in many ecosystems and food webs, they are often used as ecological indicators to evaluate the direct (e.g., collision mortality) and indirect (e.g., habitat degradation and loss, low food available) impact of wind farms. To test the effect of wind farms on the nest distribution of magpie (Pica pica), a common bird species in agroforestry systems on Chongming Island, China, the differences in magpie nest density variables and character variables were compared between quadrats inside and outside a wind farm. The relationship between magpie nest character variables and density variables in each quadrat was also examined and the impacts of landscape variables on magpie nest density variables were clarified in each quadrat. From March to December 2019, nest density variables (including total and in-use nest density) were recorded in quadrats inside and outside a wind farm in an agroforestry system on Chongming Island, Shanghai. Three nest character variables and five landscape variables were also recorded in each quadrat. The total nest density and nesting height in the quadrats outside were significantly higher than those inside the wind farm. There was a significant negative correlation between the average nest size in the quadrats and the total nest density, and a significant positive correlation between the average nesting height in the quadrats and both nest density variables. Moreover, farmland shelterbelt network cover and the distance to the nearest wind turbine were significantly positively related to the total nest density, whereas the farmland shelterbelt network cover was significantly positively related to the in-use nest density. These results indicate a negative effect of wind turbines on the nest density of magpies, which could be addressed by the provision of more farmland shelterbelt networks inside the wind farms located in agroforestry systems on Chongming Island, China. more...

В представленной статье описываются результаты изучения сезонной динамики сердечного индекса оседлых и перелетных видов птиц семейства Врановые на территории Чувашской Республики. Объектами исследований явились оседлые, кочующие и перелетный виды птиц семейства Врановые: сорока, галка, грач и серая ворона. Работа основана на материалах полевых и лабораторных исследований, которые проводились в весенний и осенний периоды 2016–2019 годов в пределах Чувашской Республики. В результате изучения параметров сердечного индекса серой вороны, сороки, грача и галки наибольшие значения данного показателя обнаружены у птиц с наименьшей массой тела и наиболее развитой летательной мускулатурой, а также у перелетных птиц. При определении сердечного индекса в весенний и осенний периоды у всех рассмотренных видов птиц выявлены достоверные межсезонные различия исследуемого параметра, что может быть обусловлено сезонными колебаниями активности и массы тела птиц. Из всех изученных видов птиц наибольшая сезонная вариабельность сердечного индекса отмечена у единственного перелетного вида – грача. Наименьшие различия между весенними и осенними значениями сердечного индекса установлены у сороки, ведущей наиболее оседлый образ жизни по сравнению с грачом, серой вороной и галкой., The following paper describes the results of seasonal dynamics study of the cardiac index of sedentary and migratory species of the Corvidae birds on the territory of the Chuvash Republic. The objects of the research were sedentary, nomadic and migratory species of the Corvidae birds: magpie, jackdaw, rook and gray crow. The work is based on the materials of the field and laboratory studies, which were conducted in the spring and autumn of 2016–2019 in the Chuvash Republic. The parameters of the cardiac index of grey crows, magpies, rooks and jackdaws were studied and birds with the lowest body mass and the most developed flying muscles, as well as migratory birds had the highest values of this indicator. When determining the cardiac index in spring and autumn, all the considered bird species had significant inter-seasonal differences of the studied parameter. It may be due to seasonal fluctuations in the activity and body mass of the birds. Of all the studied bird species only the rook had the highest seasonal variability of the cardiac index. The magpie had the smallest differences between spring and autumn values of the cardiac index, as they lead the most sedentary lifestyle compared to the rook, the crow and the jackdaw. more...

Сорока в Амурской области распространена повсеместно. Сорока, в отличие от других своих сородичей, не селится в лесах, им нужна территория, на которой они могут охотиться, а это открытая местность, на которой попадаются одинокие деревья и кусты. Сейчас для сорок стало популярным селиться в парках. В зимнее время на улицах этих птиц появляется больше, чем в летнее время, так как зимой пищи в природе становится меньше и часть птиц перебирается поближе к человеку. Амурская область относительно обитания сороки обыкновенной находится на стыке географических трех выделенных на сегодня рас восточно-сибирская, амурская и уссурийская. Амурский подвид, на основании морфометрических показателей выделяется слабо, т.е. все-таки надо считать её гибридным вариантом Pica pica leucoptera и Pica pica jankowskii. Но считается, что амурский подвид сороки имеет различия поведенческого характера, голосовых сигнальных нюансов и различия по пространственной динамике по сезонам года в пределах биотопов обитания. Исследования по теме статьи проводились на территории Амурской области. Основной объем исследований пришелся на 2017 год. В результате проведенных исследований на территории Амурской области выявлено обитание трех подвидов сороки восточно-сибирский (Pica pica leucoptera) с более синим цветом на крыле и зеленым на хвосте, амурский (Pica pica amurensis) с синим крылом и зелено-синим хвостом и уссурийский (Pica pica jankowskii) с сине-фиолетовым крылом и зеленосиним хвостом. Результаты морфометрических исследований определили морфологические различия особей разных подвидов: восточно-сибирский подвид сороки самый крупный, а уссурийский самый мелкий, амурский подвид занимает промежуточные значения по размерам, Magpies live everywhere in the Amur Region. Unlike their other congeners, magpies do not settle in the forests, as they need a territory on which they can hunt. This is usually an open area with some single trees and bushes. Now it has become popular for magpies to settle in parks. In winter, more birds appear on the city streets than in summer, as during winter there is less food for them in their natural habitats and some of the birds move closerto humans. As regards magpie's habitat, Amur Region is situated at the junction of the three geographic races, currently identified as East Siberian, Amur and Ussuri. Amur subspecies, according to morphometric parameters, is poorly distinguished, i.e. it is still should be considered a hybrid subspecies of Pica pica leucoptera and Pica pica jankowskii. But it is believed that the Amur subspecies of the magpies have behavioral differences, voice signal nuances and differences in spatial dynamics depending on the seasons of the year within the habitat biotopes. The research on the article's topic was conducted in the Amur Region. The main portion of studies was done in 2017. As the result of the study three magpie subspecies were found to be predominant on the territory of the Amur Region East Siberian subspecies (Pica pica leucoptera) with more cyan color on the wings and green on the tail, Amur subspecies (Pica pica amurensis) with blue wings and a green-blue tail and Ussuri subspecies (Pica pica jankowskii) with blue-violet wings and a green-blue tail. The findings of morphometric studies have revealed morphological differences in subspecies: East Siberian subspecies of magpie are the largest, Ussurian subspecies are the smallest and Amur subspecies are between these two in their physical sizes more...

It is well-known that some members of the crow family (Corvidae) are important for seed dispersal either via frugivory (e.g., when feeding on berries) or by scatter hoarding (e.g., of nuts). Dispersal via gut passage of seeds within a fleshy fruit can be considered “classical endozoochory.” However, corvids are rarely recognized as vectors of plants lacking a fleshy fruit, or a large nut (such as plants with a dry achene, capsule or caryopsis). Dispersal of such seeds via gut passage can be considered “non-classical endozoochory.” A century ago, Heintze (1917a,b); Heintze (1918) reported on extensive field studies of seed dispersal by 11 species of European Corvidae. His work is overlooked in contemporary reviews of corvid biology. We resurrect his work, which suggests that contemporary views about seed dispersal by corvids are too narrow. Heintze identified 157 plant taxa from 42 families which were dispersed by corvids by endozoochory, as well as another nine taxa only dispersed by synzoochory (which includes scatter-hoarding). Most (54%) of the plant species dispersed by endozoochory lack a fleshy fruit and have previously been assigned to other dispersal syndromes,mainly associated with wind (10%), self-dispersal (22%) or epizoochory (18%). Plants lacking a fleshy fruit were particularly well-represented from the Caryophyllaceae (12 species), Poaceae (14 species), and Polygonaceae (8 species). Of 27 taxa germinated by Heintze from seeds extracted from corvid pellets or feces (71% of those tested), 20 lack a fleshy fruit. Similarly, of 32 taxa he recorded as seedlings having germinated from pellets in the field, 11 lacked a fleshy fruit. However, Heintze’s quantitative data show that classical endozoochory is dominant in Magpies Pica pica and Hooded Crows Corvus cornix, for which 97% of seeds dispersed were fleshy-fruited. Corvids overlap with waterfowl as vectors of terrestrial plants dispersed by non-classical endozoochory, and 56 species are dispersed by both corvids and dabbling ducks according to the lists of Heintze and Soons et al. (2016). Finally, Heintze’s data show that corvids were already dispersing alien plants in Europe a century ago, such as the North American Dwarf Serviceberry Amelanchier spicata more...

В данной статье приводится сравнительный эколого-морфологический анализ летательного аппарата массовых видов птиц семейства Врановые: грача, галки, серой вороны, сороки. Данные виды птиц обладают разным характером полета и разной летательной активностью – среди них есть и оседлые, и перелетный виды. Исследования эколого-морфологических особенностей летательного аппарата грача, галки, серой вороны и сороки проводились на территории Чувашской Республики в осенний и весенний периоды в течение 2014–2018 годов. В статье описаны полевые наблюдения за характером полета изучаемых видов и приведены результаты морфометрических измерений. Для исследований использовались следующие морфологические параметры птиц: масса тела, длина тела, длина хвоста, длина крыла, размах крыльев, ширина крыла. Для изучения развития летательной мускулатуры птиц определялись массы подключичной и грудной мышц и индексы отношения этих параметров к массе тела и между собой. Данные показатели использовались для вычисления ряда индексов. Проведенные исследования летательного аппарата птиц выявили межсезонные различия по некоторым параметрам, связанным с массой тела. Кроме того, определены видовые особенности строения летательного аппарата рассмотренных птиц семейства Врановые, связанные с характером и скоростью полета, длительностью миграции., This paper provides a comparative ecological and morphological analysis of the aircraft of Corvidae birds: rook, daw, gray crow and magpie. These species of birds have a different character of flight and different flying activity – among them there are both resident and migratory species. Ecological and morphological characteristics of the rook, jackdaws, crows and magpies aircraft were studied in the Chuvash Republic in the autumn and spring during 2014–2018. The paper describes the field observations of the nature of the flight of the studied species and the results of morphometric measurements. The following morphological parameters of birds were used: body weight; body length; tail length; wing length; wingspan; wing width. To study the development of the avian musculature, the masses of the subclavian and pectoral muscles and the indices of the relationship of these parameters to body weight and among themselves were determined. These indicators were used to calculate a number of indices. Studies of the birds’ aircraft revealed interseasonal differences in some parameters related to body weight. In addition, the specific features of the Corvidae birds’ aircraft structure have been identified; they are associated with the nature and speed of flight as well as the duration of migration. more...

Hosts of obligate avian brood parasites use visual cues to distinguish between their own eggs and those of the parasite. Despite major differences between human and bird vision, most previous studies on cuckoo egg mimicry estimated color matching based on human color vision. Undetected by humans, ultraviolet reflectance (UVR) may play a previously ignored role for rejection behavior in avian brood parasite systems. We explored this possibility by manipulating UVR of great spotted cuckoo Clamator glandarius eggs and assessing the response of magpie Pica pica hosts. We coated cuckoo eggs with an ultraviolet (UV) light blocker that reduced UVR but left the human visible reflectance (400--700 nm) unaltered. The first control treatment also coated the eggs but did not alter their reflectance. A second control group of cuckoo eggs was maintained uncoated to control for handling effects on magpie discrimination. We artificially parasitized a third of a breeding magpie population with each type of experimental egg and studied the rejection of cuckoo eggs. We failed to find significant differences between rejection rate of cuckoo eggs with and without reduced reflectance in the UV region. Our results indicate that artificial reduction of UVR of cuckoo eggs does not affect the probability of ejection by magpie hosts. Copyright 2006. more...

Post-mating sexually selected signals are expected to indicate parental quality. The good parent model assumes that expression of the sexual character positively reflects parental ability, resulting in a potential link between the exaggeration of the character and nestling-fitness traits. We tested this prediction in a population of a monogamous passerine, the magpie (Pica pica), for which nest size is known to act as a post-mating sexually selected signal. We provided a food supplement to half of the magpie nestlings in each nest, keeping the other half as control nestlings. We found that food-supplemented nestlings experienced a significantly higher T-cell-mediated immune response and a tendency to an increased condition index. In accordance with the good parent model, we found that nest size was positively related to T-cell mediated immune response for control magpie, whereas this relationship was nonexistent in food-supplemented nestlings. In addition, the difference in T-cell mediated immune response between food-supplemented and control nestlings of the same nest was principally explained by nest size. Based on our results, we discuss that magpie pairs with large nests provided their nestlings with higher quality food as compared to pairs with smaller nests, nest size thereby being an indicator of parental ability. To our knowledge, this is the first study showing a link between a post-mating sexually selected signal and nestling immunocompetence, a trait closely related to fitness in birds. Copyright 2004. more...

Background Avian reoviruses (ARVs) cause a range of disease presentations in domestic, captive and free-living bird species. ARVs have been reported as a cause of significant disease and mortality in free-living corvid species in North America and continental Europe. Until this report, there have been no confirmed cases of ARV-associated disease in British wild birds. Case presentation Sporadic individual magpie (Pica pica) mortality was detected at a single site in Buckinghamshire, England, April-September 2013. An adult female magpie was found moribund and subsequently died. Post-mortem examination identified hepatomegaly and splenomegaly as the most severe macroscopic abnormalities. Histopathological examination revealed extensive hepatic and splenic necrosis. Transmission electron microscopy (TEM) identified virions of a size (circa 78 nm diameter) and morphology consistent with ARV in both the liver and the small intestinal (SI) contents. Nucleic acid extracted from pooled liver and spleen was positive on both a pan-reovirus nested PCR targeting the RNA-dependent RNA polymerase gene and a PCR using primers specific to the ARV sigma C protein gene. Virus isolated from the liver and the SI contents was characterised by a syncytial-type cytopathic effect, a reovirus-like appearance on TEM and sequence identical to that from PCR of tissues. In situ hybridisation confirmed co-localisation of ARV with lesions in the liver and spleen, implicating ARV as the causative agent. Splenic lymphoid atrophy and necrotic stomatitis associated with Aspergillus fumigatus infection were consistent with generalised immunosuppression and resultant opportunistic infection. Conclusions The pathology and comprehensive virus investigations in this case indicate ARV as the primary pathogen in this magpie, with concurrent secondary infection subsequent to immunosuppression, as has been observed with reoviral infections in other bird species. ARV should be considered as a differential diagnosis for magpie, and potentially other corvid, disease and mortality incidents. This is the first demonstration of ARV-associated mortality in a wild bird in Britain. The prevalence and significance of ARV infection in British wild birds, and its implications for poultry and captive bird health, are currently unknown. more...

Aquesta nota mostra la tendència poblacional de la garsa (Pica pica) al llarg del kilòmetre 1 (des de lalínea de costa, riu amunt) del paisatge protegit de la Desembocadura del riu Millars (Castelló), per alperíode comprés de 1994-2009 (16 anys). Els resultats se centren en censos realitzats a la zona mitjançantel mètode del transecte lineal duts a terme 3 o 4 vegades al mes. L’espècie se censa per primera vegadal’any 1997 i des l’aleshores mostra una tendència a l’alça sobretot a partir de 2003 i molt especialmenten els dos últims (2008-2009). S’ha estabilitzat una abundància mitjana de 8,3 aus/km. Pel que fa a lescorrelacions amb la meteorologia, en els anys més freds presenta menor abundància que en els càlids.Els hiverns càlids podrien permetre major supervivència i, a més, major disponibilitat de recursos ambels quals assegurar un bon nombre de polls. L’espècie troba en la zona suficients recursos tròfics persobreviure i un lloc excel·lent on lliurar-se de la pressió cinegètica.Population tendency of the magpie (Pica pica) in the period 1994-2009 at the mouth ofthe Millars river (Castelló)This note shows the population trend of the magpie (Pica pica) over 1 kilometer (up river from the coastline) of the protected landscape of the mouth of the Mijares river (Castellón), for the period of 1994-2009 (16 years). I focus on census conducted in the area by the method of linear transect, carried out 3or 4 times every month. The species was registered for the first time in 1997 and since then it shows anupward trend, especially after 2003 and more so in the last two years (2008-2009). Abundance has stabilized arround an average of 8.3 birds/km. Regarding correlations with weather, the species presentedlower abundance in cold years than in warm ones. Cool winters could allow higher survival rates and increased resources availability to breed a higher number of youngs. The species founds in the area sufficient food resources to survive and an excellent place to avoid hunting pressure. more...

El presente estudio tiene como objeto analizar la abundancia y distribución de la urraca en función de las diferentes matrices de usos del suelo y gradientes ambientales. Este trabajo se ha centrado en la Comarca de la Marina Baja (Alicante), una región con 578,8 Km² de superficie. La zona cuenta con una vegetación climática de carrascal de termotipo mesomediterráneo y ombrotipo seco y subhúmedo. Se han realizado un total de 396 transectos para estimar la abundancia de la urraca durante los años 2006-2008, en diferentes matrices del paisaje: natural, abandono, regadío y secano. Las abundancias relativas, la evolución de la especie, el efecto sobre otras especies de caza y el efecto que tiene el control poblacional de las urracas se ha obtenido de 21 encuestas realizadas a los gestores de los terrenos cinegéticos. El análisis de los resultados, muestra una mayor abundancia de los individuos en zonas de cultivo de secano (IKA=0.76 aves/km) y cultivos abandonados (IKA=0.73 aves/km), siendo los valores medios anuales cada vez mayores desde el inicio del muestreo. El análisis múltiple de regresión lineal de la abundancia de urraca con la matriz de usos del suelo muestra una relación significativa y positiva con el abandono antiguo (p0.05) con los índices del paisaje. El análisis ANOVA muestra que las variables significativas influyentes sobre el número de urracas son: matriz de usos del suelo, latitud/ombroclima, continentalidad y la interacción usos del suelo:continentalidad (p 0.05) with landscape indices. ANOVA analysis shows that the significant variables influencing the number of magpies are: landuse matrix, latitude/ombroclimate, continentality and interaction landuse:continentality (p more...

This study examined the influence of winter social behavior, particularly dominance relationships, on the subsequent nesting habitat selection and reproductive success of Black-billed Magpies (Pica pica hudsonia) on 2 areas in northern Utah. Hierarchical cluster analysis ordinated the habitats available to breeding birds and Chi-square and Bonferoni-z statistics were used to determine those habitat types the magpies seemed to prefer. Social status was determined by observing color-banded birds engaged in agonistic encounters at winter bait stations. Social dominance was evaluated by % dyads won, not by total % victories. Relationships between winter social status of magpies and their subsequent breeding habitat use and reproductive performance was tested by Kendall's Tau. Winter foraging flocks were comprised primarily of juvenile (1st year) birds while adults tended to remain as isolates or in pairs. Social status within flocks was correlated with age and sex; males dominated females and juvenile males dominated adult males. This was caused by differences in the social organization of adults and juveniles which created asymmetric views of winter food resources between male age classes. Breeding territories were densely packed in all habitats with a mean size of 0.5 ha. Date of clutch initiation was significantly correlated with clutch size and number of fledglings, with earlier nests more successful. Juveniles occupied marginal habitats and produced fewer offspring than adults. Within a dominance hierarchy of juvenile males, no significant differences in reproductive variables were detected except date of clutch initiation and weight of nestlings. Nestlings of dominant parents fledged earlier and were heavier than those of subordinates, which should increase post-fledging survival. This study has documented, for the first time in a free-living population, relationships between characteristics of nestlings and their future dominance status. Two characteristics, fledging date and rank (by weight) in the brood, were correlated with future winter dominance of juvenile males. The dominance status of male magpies is associated with many factors related to relative fitness, with hereditary components moderated by environmental and social factors. more...

In 1984 studies were initiated to identify the bird species causing damage to pistachio nuts, quantify the losses, and explore possible methods for alleviating bird losses. The first year's field observations were made to identify and determine the level of activity of the various depredating bird species in the orchard. Field samples of nuts were collected to assess the levels of damage occurring in representative orchards. A mail survey of all commercial pistachio growers in California was conducted to determine which bird species growers believed were the cause of nut losses, the extent of damage they have experienced and what, if any, bird control methods they have used. The objective of the second year was to further evaluate production losses due to crows and scrub jays. During the damage season, evaluation of various types of baits for crows and scrub jays was made in several pistachio orchards. Finally, with most growers reporting the use of shooting to frighten and disperse the birds from the orchard, an initial effort to evaluate shooting as a control method was made. more...

Background: Corvidae is a cosmopolitan family of oscine birds including crows, rooks, mag­pies, jays, chough, and ravens. These birds are migratory species, especially in the shortage of foods, so they can act like vectors for a wide range of microorganisms. They live generally in temper­ate climates and in a very close contact with human residential areas as well as poultry farms. There is no available information in the literature concerning the parasitic infections of these three species of corvidae in Mazandaran Province, northern Iran, so this study was con­ducted to clarify this. Methods: As there are three species of corvid birds in Mazandaran Province, 106 birds including 79 magpies, 11 rooks, and 16 carrion crows were examined between winter 2007 and spring 2008 at post mortem for gastrointestinal helminths. The helminths were drawn and identified morphologi­cally in the Laboratory of Parasitology, Islamic Azad University, Science and Re­search Branch, Tehran and also partly in the School of Public Health, Tehran University of Medical Sciences, based on the reference books and identification keys like Soulsby, Khalil et al. and Anderson et al. Results: Four species of nematodes, 2 species of cestodes, 1 species of trematodes and 1 species of acanthocephalans were identified in these three corvid species. Conclusion: Five species of the helminths are identified for the first time in Iran, and the acantho­cephalan species is new host record for rooks. It is clear that these corvid birds have di­verse range of helminths and can act as carriers for infecting the domestic fowls. more...