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1

Reproductive success of Yellow-billed Magpies Pica nuttalli in central coastal California

100%

Reynolds M. D., Koenig W. D.

Acta Ornithologica

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1997

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tom 32

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nr 1

99-109

Yellow-billed Magpies in central coastal California had significant variation in laying date of first egg and clutch size within and among years. The length of the breeding season was shorter than for other magpies, but timing of breeding varied widely among years. Early breeders laid larger clutches and, for successful nests, fledged more young than later breeders. Breeding coincided with peak food abundance and breeding early, relative to a particular year's food peak, resulted in higher reproductive success. However, variation in annual reproductive success was not correlated with precipitation or temperature. First-year and mixed-age pairs laid later and smaller clutches than older pairs. First-year females fledged fewer young than older females. Heavier females laid eggs earlier than lighter females. Number of breeding attempts was the most important determinant of reproductive success among years.

2

Indywidualne znakowanie wron amerykanskich [Corvus brachyrynchos] poprzez odbarwianie pior

100%

Romanowski J., Reed L., Caccamise D. F., Stouffer P.

Notatki Ornitologiczne

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1993

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tom 34

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nr 1-2

157-161

3

Spadek liczebnosci srodpolnych ptakow krukowatych Corvidae w poludniowo-zachodniej Polsce

100%

Tomialojc L.

Chrońmy Przyrodę Ojczystą

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2009

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tom 65

|

nr 6

415-422

Po wzroście liczebności w połowie XX wieku potem w południowo-zachodniej Polsce polne ptaki krukowate Corvidae (w przeciwieństwie do miejskich) silnie zmniejszyły swoje populacje. W niniejszej pracy porównano nieliczne konkretne dawne dane ze stanem obecnym. Liczebność wrony siwej Corvus cornix na trzech dolnośląskich powierzchniach próbnych badanych w latach 1960. lub 1970. oraz ostatnio (2008–2009) zmniejszyła się ponad 30-krotnie, z 7–53 p do 0–2 par. Obserwacje z pociągu (wzdłuż ok. 1250 km tras) potwierdziły obecną niską jej liczebność na rozległym obszarze południowo- zachodniej Polski, jak również sugerują obecną niską liczebność gawronów C. frugilegus, kawek C. monedula i śródpolnych srok Pica pica. Przyczynami jest prawdopodobnie splot dwóch czynników: a) zastąpienie niskotrawiastych pastwisk oraz upraw buraka cukrowego i ziemniaków przez wysokotrawiaste łąki oraz wielkopowierzchniowe uprawy zbóż ozimych, rzepaku i kukurydzy; b) pojawienie się i wzrost liczebności kruka Corvus corax. Dwa rodzaje obserwacji oraz test wokalny sugerują, że zniknięcie z krajobrazu rolniczego bardzo widocznych gniazd wron i srok, może być spowodowane drapieżnictwem gniazdowym kruków

4

Smiertelnosc ptakow krukowatych Corvidae na noclegowisku zimowym w Siedlcach w sezonie 2000/2001

100%

Kasprzykowski Z.

Notatki Ornitologiczne

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2002

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tom 43

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nr 1

52-53

5

Wrony siwe [Corvus corone cornix] rozbijaja orzechy zrzucajac je na ziemie

100%

Lorek G., Oleksik I.

Notatki Ornitologiczne

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1992

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tom 33

|

nr 3-4

331-332

6

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Dwa lęgi pary kruka Corvus corax w jednym sezonie

84%

Stepniewski J., Luczak A.

Ornis Polonica

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2015

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tom 56

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nr 4

7

Wing plumage variation and genetic, relatedness in the European Black-billed Magpie Pica pica

84%

Parrott D.

Acta Ornithologica

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1997

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tom 32

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nr 1

87-92

Black-billed Magpies possess distinctive patterns of black and white on their flight feathers which have been suggested to be family-specific. Such a phenomenon could potentially provide a simple field-method for recognising related or unrelated offspring. Using a combination of wing plumage patterns and multilocus DNA fingerprinting the relationship between plumage variation and genetic relatedness in the European Black-billed Magpie was investigated. The plumage of nestmates was more similar to each other than to young in other nests. However, extra-pair offspring could not be identified from nestmates through plumage differences. Within brood similarity may be explained by full-siblings sharing plumage characteristics through random inheritance, or through a shared rearing environment. Extra-pair offspring may resemble their half-sibs due to shared maternal plumage characteristics and a common rearing environment.

8

On the abundance of the Magpie Pica pica during breeding and winter season in Berlin

84%

Witt K.

Acta Ornithologica

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1997

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tom 32

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nr 1

121-126

Magpie Pica pica is widely distributed over the built-up areas of Berlin. A population increase is observed at least from the 60s up to now. Over about 20 years population changes are documented in different parts of Berlin. Some main lines of increase are shown for two different habitat types: residential district and closed built-up zone of the city. The method of territory mapping was applied including search for nest stands. The population changes are different for both parts (less steep in the residential district). Recent abundances in the central block building districts exceed those from the residential districts, however, the new top number ist 32 p/km² for a high-rise building area. Since 1991, winter birds were censused in different habitats of Berlin since 1991, during the winter periods 1991 and 1992 with varying plot size, and from 1993 to 1995 on 5ha plots. Magpie uses the residential district with high frequency and abundance. There is some concern about comparability of abundances from winter and breeding seasons. The daily range of a roosting winter community of up to 420 birds is estimated at about 12 km², which means an abundance of up to 3,5 ind./10ha rather near to numbers found on 5ha plots, however, exceeding numbers expected from the breeding season. Henceforth, during winter time Magpies may prefer other habitat types than in the breeding season.

9

Zimowe zgrupowanie gawronow Corvus frugilegus w Europie

84%

Jadczyk P., Jakubiec Z.

Przegląd Zoologiczny

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1995

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tom 39

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nr 3-4

297-312

10

The ecology of the Black-billed Magpie Pica pica sericea in Japan

84%

Eguchi K., Takeishi M.

Acta Ornithologica

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1997

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tom 32

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nr 1

33-37

The Black-billed Magpie, Pica pica sericea, was introduced in Japan from Korea about 400 years ago. It inhabits a restricted area in northern Kyushu, but has relatively high nesting density in some areas (> 20 pairs per km²). Most nests are built in the vicinity of human habitation, even in the midst of cities. Most clutches are laid in March and April. Mean clutch size (6.2) and mean number of hatchlings (4.2) are within the ranges of values for European and North American races. Nesting success is low, with only 18% of clutches surviving to fledge. Predation, mainly by crows, is a major cause of failure, accounting for 81% of clutch loss and 84% of brood loss. Low nesting success may have taken place in recent years. Nests on utility poles are more successful than those in trees. Nesting on utility poles has been increasing, occupying more than 50% of total number of nests. The range of the Black-billed Magpie has been gradually expanding in Japan.

11

First report of hepatic cysticercosis in a Rook (Corvus frugilegus) (Passeriformes, Corvidae)

84%

Nourani H., Dehkordi H. A., Soltani S., Khosravi M.

Annals of Parasitology

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2014

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tom 60

|

nr 4

Cysticercosis is an infection with the larval (cysticercus) stage of Taenia spp. that it is seen as cysts in various human and animal tissues. In this study, pathologic findings of hepatic cysticercosis in a rook (Corvus frugilegus) is described. To our knowledge, there is no report on hepatic cysticercosis in rook and this study shows that rooks may play a role as intermediate hosts in the transmission of parasitic infections.

12

Extra-pair copulations in Yellow-billed Magpies Pica nuttalli: preliminary results

84%

Bolen G. M.

Acta Ornithologica

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1997

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tom 32

|

nr 1

9-13

The adaptive significance of female extra-pair copulation behavior was investigated in Yellow-billed Magpies, Pica nuttalli, a socially monogamous species. Research was carried out in central coastal California, U.S.A. Observations of female behavior towards extra-pair males during the breeding season suggest that females display a preference for certain extra-pair males. In addition, observations confirm that females can successfully resist male copulation attempts. However, based on a small sample, no significant difference in fledging success was found for nests at which extra-pair visits occurred and those at which they did not. Multilocus DNA fingerprinting analysis is in progress to determine the rate of extra-pair fertilizations. These data will be analyzed for correlations between female behavior towards extra-pair males and those males successfully gaining extra-pair fertilizations, and for differences in fledging success between nests with extra-pair fertilizations and those without extra-pair fertilizations.

13

Numbers and distribution of the Magpie Pica pica in Lvov [Ukraine]

84%

Bokotey A. A.

Acta Ornithologica

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1997

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tom 32

|

nr 1

5-7

Research on the Magpie Pica pica was conducted in the limits of urbanized part of Lvov (66.5km2) in the summer of 1994-1995, and the winters of 1993/94 and 1994/95. The work was based on an ecological (landscape mosaic) division of the city. The number of breeding Magpies was estimated to be 520 pairs (0.8 pair/10ha). The highest density of birds was recorded in parks and areas of one family houses (1.2 pair/10ha), less in the modem housing estates (0.7 pair/10ha), and the lowest in the central and industrial districts (0.4 pair/10ha). The number of wintering Magpies in Lvov is about 2000 (3 ind./10ha). The highest density was recorded in rural zones of the town (8.4 ind./10ha), the least in the industrial zones (1.8 ind./10ha). In winter outside of the town Magpies were counted at a communal roost, which gathered up to 1700 individuals.

14

Urban and natural components of Korean magpie (Pica pica sericea) territories and their effects on prey density

84%

Kim S., Srygley R. B., Lee J. Y., Lee S.-I., Choe J. C.

Polish Journal of Ecology

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2012

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tom 60

|

nr 2

Urban landscapes have a negative impact on bird species diversity, yet particular species thrive in urban communities. Like many other corvids, the Korean magpie is a successful colonizer of urban environments. On the semiurban campus of Seoul National University in Korea, we investigated whether magpies adjust territory size with building area and secondarily, whether they use vegetation and artificial components of their territory as indicators of prey density. We measured territorial areas and divided these into vegetation and artificial areas, distinguishing building area as a separate feature. We sampled prey density on each territory during the nestling stage. Territory size increased with the square root of building area (SRBA). As the length of building perimeter also increases with SRBA, we conclude that territory size was proportional to building perimeter. Prey density decreased with SRBA indicating that buildings had a negative impact on prey. Breeding success was also negatively related to SRBA. We suggest that magpies adjusted territory size according to the length of building perimeter due to a decline in prey density. As prey density declined, artificial pavement area was added to include open trash bins, which increase the availability of anthropogenic refuse such as discarded food. Vegetation area declined as prey density increased, but changes in vegetation area were minor and had little impact on prey availability measured at ground level. Structural cues were not used to adjust vegetation area, and artificial structural cues were not used to adjust territorial size over direct monitoring of prey density.

15

Variation in the wing patches of juvenile Black-billed Magpie Pica pica

84%

Reed L. M., Wang X., Trost C. H.

Acta Ornithologica

|

1997

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tom 32

|

nr 1

93-97

Variability in morphological features is one mechanism by which recognition of individuals or kin, crucial to many social interactions, can occur. Patches in the remiges of magpie wings (white patches with black tips) contain information regarding the bearer's age and sex. Juvenile wing patches of both Black-billed Pica pica hudsonia and Yellow-billed Magpies Pica nuttalli contain between 10 to 12 feathers with variable lengths of white. Our investigations examine the relationship between wing patch morphology and relatedness. We measured the black tips on the primaries of one wing on 29 fledglings from seven nests. We derived a discriminant function based on the length of black on three inner primaries that successfully assigned 75 % of the birds to their natal nests (random assignment = 14% correct). We also compared the total length of black tips in the wing patches of young from 33 nests. We found less variation in the patch size within than between nests (log transformed ANOVA F = 8.339, p < 0.001; Kruskal-Wallis H = 113.6, p < 0.001). These results suggest that familial resemblance is encoded in juvenal magpie wing patches. Family recognition may be important both to the parents, who provide protection and food for their young, as well as between siblings, who apparently know each other.

16

Liczebnosc populacji legowej gawrona Corvus frugilegus w Agroekologicznym Parku Krajobrazowym kolo Turwi w roku 1995

84%

Tryjanowski P.

Przegląd Przyrodniczy

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1996

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tom 07

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nr 2

55-59

17

Advantages of early versus late nesting in Black-billed Magpies Pica pica hudsonia variation in productivity, sex ratio, and fledgling size

84%

Gersteli A. T., Trost C. H.

Acta Ornithologica

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1997

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tom 32

|

nr 1

39-44

Studies of Black-billed Magpies Pica pica hudsonia in Idaho, USA showed greater reproductive success in early nests. Overall, offspring from early nests were larger in body size and had longer bill lengths, both characteristics associated with social dominance in the non-breeding flock. Preliminary determination of the sex of nestlings shows: 1) a disproportionate number of male nestlings in early nests; 2) both male and female nestlings are heavier in early nests than later nests; and 3) in contrast, bill lengths are greater in early males but early and late females have the same bill length. Females in our study area do not use their bills in social displays. The anatomical traits of males from early nests are associated with higher social status and thus higher eventual nesting success. This indicates that even as nestlings, Magpies acquire physical characteristics related to social status and eventual probability of breeding. We are currently unable to determine if this is due to differential parental investment throughout the nesting period, or whether it is due to differing environmental effects within early and late nesting periods.

18

Niezwykla kolonia gawrona [Corvus frugilegus] na wyspie jeziora Galadus

84%

Sikora A., Kapowicz R.

Notatki Ornitologiczne

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1996

|

tom 37

|

nr 1-2

152-153

19

Winter roosting of Rooks Corvus frugilegus in Wroclaw

84%

Jadczyk P.

Acta Ornithologica

|

1994

|

tom 29

|

nr 1

39-47

In the 1988/1989 and 1989/1990 seasons, the winter grouping of corvids in the city of Wrocław (Lower Silesia, Poland) included 200,000-250,000 individuals, of which 92-94% were Rooks, 6-8% Jackdaws Corvus monedula and about 0.1% Hooded Crows Corvus corone cornix. Young Rooks made up 5-6% of the population. Numbers were estimated by counting flocks during their flights to the roosts. Rooks wintering in Wrocław nest on the Russian Plain, but probably also include a small number of birds grom the dty itself. In the course of the last 30 years, the size of the grouping of corvids has increased 10-fold, with numbers of Rooks increasing 20-fold and numbers of Jackdaws increasing by up to a half. Mean mortality of Rooks at the roosts was 0.74 individuals per night i e. 0.3%₀ of the whole population per wintering season. Of the birds dying, one-third were young. Corvids roosted in several roosts which were used to different extents. At least two were used regularly as primary roosts and the oldest roost had been used for over 40 years. Corvids foraged within 15-20 km of the roosts. Flights between the roosts and the foraging areas followed regular, permanent air corridors, according to a permanent scheme of gathering in places which were stages in the flight. The Rooks kept quiet at the roosts and during their flights. They foraged by actively seeking out food and by passively waiting for food to be thrown out by people. Their behaviour was wary.

20

Ultrastructure of the spermatozoon of Paroniella reynoldsae [Cyclophyllidea, Davaineidae] an intestinal parasite of Corvus albus [Aves, Corvidae]

84%

Ba C. T., Ba A., Marchand B.

Acta Parasitologica

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2005

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tom 50

|

nr 3

The mature Paroniella reynoldsae spermatozoon exhibits an apical cone of electron-dense material about 2.2 µm long and 0.65 µm wide at its base and two helicoidal crest-like bodies roughly 100 to 150 nra thick. The latter are of different lengths, spiralled and make an angle of about 45° with the spermatozoon axis. The axoneme is of the 9 + '1' trepaxonematan pattern and does not reach the posterior extremity of the gamete. The nucleus is an electron-dense cord 0.25 µm thick coiled in a spiral around the axoneme. The cytoplasm exhibits a posterior densification and contains few small electron-dense granules in regions I, II and V of the spermatozoon. In regions III and IV, it is divided into irregular compartments by walls of electron-dense material. The cortical microtubules are spiralled at an angle of about 45°. The presence of an electron-lucent apical cone containing numerous small granules of electron-dense material has never, to our knowledge, been reported in a cestode. Likewise, a crest-like body forming a terminal spot of electron-dense material located in the prolongation of the apical cone has never been described before in a cestode. Moreover, in this study, we try to show the existence of tight reciprocal phylogenetic relationships between genera within the Davaineidae and the Anoplocephalidae.

Ograniczanie wyników

Reproductive success of Yellow-billed Magpies Pica nuttalli in central coastal California