bluuebunny/crossref_metadata_2025 huggingface dataset:
MIGRATION IN IRAQ
Authors: Marchant S.
Published: April 2008

Migration in Iraq is discussed on the basis of three years' experience supplemented by data from other unpublished sources and the literature.

The migration of certain passerine and near‐passerine species is considered, particularly as regards comparative numbers seen in spring and autumn, and the question of their passages between breeding quarters in the Palaearctic and winter quarters in Africa, in relation to weather, geography and ecology of the Middle East. Of about 50 species discussed, half are clearly more abundant in spring, and most of the rest probably are; thus supporting the idea that such species in autumn may make longer unbroken flights than in spring. For a number of these species the nearness of the breeding quarters to Baghdad is stressed.

Exceptions are Streptopelia turtur, Alaudidae, hirundines and perhaps Motacilla flava, which are prominent, and even the only, visible daylight migrants among such small birds. These cross Iraq from east to west in autumn in vast numbers and are thought to migrate round the Fertile Crescent past Damascus, rather than fly direct towards Africa. Comparisons are made with the Mediterranean region and the rest of the Arabian peninsula, and some comments are added on the matter of broad‐front and narrow‐front migrations.

In an appendix the most important aspects of migration of large non‐passerine birds in Iraq are discussed.
SUB‐FOSSIL BIRD REMAINS ON ASCENSION ISLAND
Authors: Ashmole N. P.
Published: April 2008

Bird bones and feathers found in phosphate deposits and fumaroles on Ascension during the B.O.U. Centenary Expedition were used to supplement the historical records in building up a picture of the original avifauna of the island. The remains which can be definitely identified provide strong circumstantial evidence that the sea‐bird colonies on the main island included at least the following species: Oceanodroma castro, Phaethon aethereus, Sula sula, S. dactylatra, Fregata aquila and Sterna fuscata: a skull apparently of Gygis alba was also obtained. No remains definitely referable to Phaethon lepturus, Sula leucogaster or Anous stolidus have yet been found, but it seems very likely that these species also nested in numbers on the main island of Ascension, while Anous tenuirostris, which still nests on the cliffs of the main island, doubtless also did so in the past.

In addition to sea‐birds, a skull and a tarso‐metatarsus of a small rail, found in separate localities, probably represent the extinct flightless species described by Peter Mundy. The rail whose bones were obtained is provisionally considered as a new member of the genus Rallus.

The only surviving species that is endangered locally is the Red‐footed Booby Sula sula: the history of this species on Ascension is discussed.
EGG DIMENSIONS OF SOME ASCENSION ISLAND SEA‐BIRDS
Authors: Stonehouse Bernard
Published: April 2008

The lengths and greatest diameters of over 2,000 eggs of ten species of sea‐birds were measured on Ascension Island and off‐lying stacks; some eggs were also weighed. Means with standard deviations and extreme measurements are presented, together with brief descriptions and a short discussion of egg shape, size, and variability within and between species.
NOTES ON ECUADORIAN BIRDS
Authors: Lévêque Raymond
Published: April 2008

Occasional observations were made during 1960–62 mainly around Quito and Guayaquil, to supplement the works of Chapman (1926) and Marchant (1958). Three species are mentioned for the first time from western Ecuador and one from the Amazonian side; 34 North American migrants were seen. Data are provided for several tropical species ranging up to the Sierra. The existence of a large mixed heronry on the Guayas is also mentioned.
THE PECKING RESPONSE OF YOUNG ARCTIC TERNS STERNA MACRURA AND THE ADAPTTVENESS OF THE “RELEASING MECHANISM”
Authors: Quine D. A. , Cullen J. M.
Published: April 2008

Experiments were made using models to analyse the stimuli evoking the pecking behaviour of young Arctic Terns, with comparative tests on Herring Gulls in one year. Some of the findings for the Arctic Tern may be summarized as follows. The chicks pecked at red, blue and silver more than at orange, yellow, green, black and white, and the response was increased by adding a contrasting spot to a beak. A plain red beak, the natural colour in the breeding season, was pecked less than one tipped with black, the colour in the winter. Chicks responded more to the beak models when a “fish” was attached (Fig. 1). Under natural conditions the chicks swallow their food, chiefly the sandeel Ammodytes, head first, and this is facilitated by the chicks pecking more at the head than the tail end of the fish. The stimuli by which head and tail are distinguished were found to be the pattern of the eye and tail‐fin rather than the shape of head and tail.

The view that the selectiveness of the tern chicks is adapted specifically to the feeding situation is discussed critically, using the comparative results from the Herring Gull tests, and it is argued that while this is not the case for some of the stimuli effective in evoking the pecking (e.g. movement), whose adaptive significance concerns the general efficiency of the eye, it could well be responsible for some of the selectiveness found (e.g. high response to blue, low response to tail‐fin patterns). Comparison of the two species suggests that the Arctic Tern is specially adapted to respond to fish‐like objects attached to the beak. In the Herring Gull the ability to distinguish the head and tail of a fish appears to anticipate the time when the chick requires it.
THE BREEDING BIOLOGY OF THE SHELDUCK TADORNA TADORNA
Authors: Hori John
Published: April 2008

Breeding biology of Shelduck was studied in England on the Isle of Sheppey, Kent. Virtually complete separation of breeding and non‐breeding sections of the population occurred and non‐breeders gathered at two feeding areas which were also the foci of the winter population.

Pairing of first spring females usually occurs in the non‐breeding flocks and bonds are then of long duration.

There is an excess of males throughout the year and during the winter, particularly in February, these attempt to pair up by breaking into established pair bonds. Some probably succeed.

Flocks of adults in early April were demonstrated to be potential breeders: such flocks appear to provide mutual stimulation. Smaller, socially discrete groups of breeding adults were discovered and named “communes”. These nested together, held adjacent territories and remained in contact throughout the breeding season, even when most pairs had lost nests. They are considered to be the basic social unit of breeding populations, perhaps of all populations.

Breeding birds were unevenly distributed such that the density of all nests was one per 230 acres, but the maximum was 6 per acre.

Average clutch size of 10·1 and mode of 8 were found from nest records, compared with 8·8 and 9 respectively deduced from broods of ducklings less than three days old. Egg laying began at the end of April and lasted about 81/2 weeks.

Incubation spanned some 10 weeks from early May; individual periods averaged 30 days. An automatic recorder showed that one female spent 87% of the available time incubating.

Shelduck were found to be single brooded and no evidence of re‐nesting occurred.

The brood period started in early June and lasted about 9 weeks. Crêching was considered to result mainly from desertion by parents, but over‐crowding was also a factor. Fledging takes approximately 61/2 weeks.

In 1962 and 1963 approximately 54% and 59% respectively of the summer population attempted breeding. Success in getting broods to water (called duckling success) varied from 23·9% to 73·8% in the period 1960 to 1963. This represented a breeding success of 16% to 49·2%. Duckling losses appeared to be heavy.

Shelduck generally breed first in their second spring, but some males may not breed until they are almost five years old.
THE FOOD OF SOME LARUS GULLS
Authors: Harris M. P.
Published: April 2008

The food of L. argentatus on Skomer and Skokholm Islands (Wales) was studied by the analysis of stomach contents, pellets and direct observation. L. argentatus is mainly a scavenger and exists for the most part on fish‐waste and garbage discarded by man. At Ncwborough Warren argentatus feeds more on arable land and on the shore than do the Skokholm and Skomer birds.

Although argentatus frequently eats limpets Patella spp., there is little competition for food between them and Oystercatchers Haematopus ostralegus because the two species eat different sized limpets.

A summary of previous studies into the food of argentatus is given.

L. marinus is mainly a predator feeding on the young of other gulls, sea‐birds and Rabbits but it also eats carrion, offal and fish‐waste when available and during the winter. The numbers of Manx Shearwaters Procellaria puffinus killed on Skokholm and Skomer are discussed.

L. fuscus obtains most of its food on the shore and on arable land. There appears to be little competition, at least in the areas studied, between .fuscus and argentatus for food.
THE BREEDING BIOLOGY OF THE BLACK‐FACED DIOCH QUELEA QUELEA IN NIGERIA
Authors: Ward Peter
Published: April 2008

A study of the breeding biology of Quelea quelea in Nigeria, and particularly at a large breeding colony near Lake Chad, showed that losses of eggs and young were extremely small. 95% of eggs laid hatched successfully, and 87% give rise to fledglings. Nestling deaths were density‐dependent and apparently due to starvation.

The incubation period was 10 days or less. By day, eggs were heated to 34°‐ 37° C. by the sun; at night the females incubated. The nestlings were initially fed mainly on insects, their diet gradually changing to one of seeds—mostly of the grass Echinochloa pyramidalis. The deep body temperatures of young birds were determined. It is suggested that the nestlings left the nest after, on average, 111/2 days to escape intolerable temperature conditions in the nest.

Fat reserves were accumulated by nestlings and fledglings, and were utilized when the young became independent. The adults put on fat during the incubation period and lost it during the time spent feeding nestlings.

It is concluded that the most common clutch‐size of Q. quelea, which is everywhere three, corresponds to the largest number of young the parents can normally nourish. This conforms to Lack's theory on the significance of clutch‐size, and gives no support to Skutch's opinion that the theory does not apply to tropical birds.
PALAEARCTIC MIGRANTS IN NIGERIA
Authors: Elgood J. H. , Sharland R. E. , Ward P.
Published: April 2008

An account is given of the topography, climate and vegetation belts of Nigeria to illuminate the ecology of the Palaearctic migrants to the country.

The faunistic relationship of the resident and migrant avifauna is considered and it is shown that approximately one species in six is migrant. It is shown that the more arid vegetation belts support the largest numbers of migrant species, the forest belt supporting only very few species. Some species appear to overfly the most northern areas.

Rather few observations of visual migration are available but those known are recorded. A summary of ringing recoveries affecting Nigeria is given and it is shown that there is clear evidence of species returning to the same wintering grounds each year.

The status of 135 migrant species is briefly treated and other species are mentioned where negative information is valuable.

Calandrella rufescens, Cyanosylvia svecica, and Emberiza hortulana, notmentioned by Bannerman (1930‐53) are included and Cettia cetti is recorded from West Africa for the first time. Several species have had their range extended to include Nigeria.

A comparison of breeding areas with the Mediterranean/Sahara crossing zones and Nigerian occurrences shows that most terrestrial species in Nigeria move fairly closely to the lines of longitude. Many aquatics, mostly herons and ducks, breed much to the east of the longitude of Nigeria.

It is suggested that the unexpected number of Palaearctic migrants which winter in the arid north of Nigeria indicates that food is less scarce than the appearance of the country in the late dry season indicates. There is a great need for an ornithological and ecological research station in Nigeria in an area such as southwest Lake Chad.
POLYMORPHISM AND PARALLELISM IN THE AFRICAN BUSH‐SHRIKES OF THE GENUS MALACONOTUS (INCLUDING CHLOROPHONEUS)
Authors: Hall B. P. , Moreau R. E. , Galbraith I. C. J.
Published: April 2008

PART 1

Remarkable parallelism exists between two groups of shrikes in the genus Malaconotus: (1) small‐billed birds (formerly Chlorophoneus) comprising the polymorphic species multicolor and nigrifrons, the dimorphic olivaceus and the monomorphic sulfureopectus; (2) large‐billed birds (formerly Malaconotus sensu stricto)—of the species blanchoti, cruentus, lagdeni, gladiator and alius (and including monteiri).

Characters and ranges of the various species are set out and parallelisms between the two groups are listed. M. monteiri is thought to be a colour phase of cruentus rather than a race of blanchoti.

It is suggested that the parallelisms are due to the two groups having derived from a common ancestor and that the existing “Malaconotus”, which are monomorphic, may derive directly from polymorphic ancestral stock.

part 2

The polymorphism in “Chlorophoneus” can be accounted for by three genes with two alleles each, all interacting with polygenic systems. The homology of the morphs with the colour patterns of monomorphic populations is discussed, and their distributions in the two groups summarised.

The interaction of polymorphism with continuous variation in determining the proportion of red to yellow carotenoid is discussed.

The evidence bearing upon the status of monteiri is considered.

The difference in the incidence of polymorphism between the groups is considered in the light of the analysis into dimorphisms.

Some suggestions are made on the significance of parallels between the groups.
BIRD RECORDS FROM SOUTHWESTERN ECUADOR
Authors: Mills Eric L.
Published: April 2008

Observations are given for 25 species of birds seen in southwestern Ecuador or just offshore near the mouth of the Gulf of Guayaquil to supplement the records of Marchant (1958) and Lévêque (1964). Of the 25 species listed, 19 are sea‐birds and a number are species not commonly reported from the area. Two records of the Antarctic Fulmar Fulmarus glacbloides are given, one of which may be the first for Ecuador. The presence of Sooty Terns Sterna fuscata and possibly a few Brown Boobies Sula leucogaster just north of the Santa Elena Peninsula is unusual and was probably the result of an incursion of warm water from the west or north. In May 1966 450 + boobies, 10 Sooty Terns and 350 Brown Pelicans were counted on Isla Pelado (El Viejo) in Bahia de Santa Elena.
PNEUMATIZATION OF THE CRANIUM OF THE ZEBRA FINCH TAENIOPYGIA CASTANOTIS
Authors: Serventy D. L. , Nicholls C. A. , Farner Donald S.
Published: April 2008

The process of cranial pneumatization in the Zebra Finch Taeniopygia castanotis is substantially similar to that described in the House Sparrow Passer domesticus, but is completed somewhat earlier. Full pneumatization of the cranium is usually attained between 138 and 153 days from hatching, though in some birds it may be retarded. A series of diagrams, representing 41 stages in the process, enables the ages of young birds to be established.
WEIGHTS OF THE CARMINE BEE‐EATER MEROPS NUBZCOZDES
Authors: Britton P. L.
Published: April 2008

A total of 912 Carmine Bee‐eater Merops nubicoides weights were obtained at Beatrice, Rhodesia in November 1963, September 1964 and Novembels‐pecember 1965. On average the birds weighed least in the early morning and most in the late evening. Some interesting peculiaritiee in the diurnal rhythm of weights are correlated with feeding activity and the feeding of young.

There was no clear correlation between air temperature and weight. It is suggested that an inverse correlation between temperature and weight is obscured by the fact that temperature has a direct effect on food supply and this in turn influences weights. Mean weights varied significantly with variation in food supply; one particular instance of the effect of a special food supply on weights is discussed in detail.

Birds were heavier in November (rainy season) than in September (dry season). It is suggested that food is not readily available in September and that this weight change is a response to improved food‐supplies.

On average, the mean juvenile weight is 82% of the mean adult weight. The weights of five juveniles, known to be out of the nest for eight days or less, varied by as much as 56% of the lowest.
WATER‐BIRDS OVER THE SAHARA
Authors: Moreau R. E.
Published: April 2008

An investigation is made of the extent to which Palaearctic birds belonging to typically water‐bird families occur south of the Sahara in areas remote from both the sea and the Nile, namely, Darfur, Northern Nigeria and the Inundation Zone of the Niger, and hence may be presumed to cross the Sahara. Fifty‐seven species fall to be considered and for these occurrences within the Sahara are also collated. The results owe a great deal to work done in the last few years, especially ringing.

Most of the 57 species dealt with occur regularly in appreciable numbers in one or more of the areas under consideration and some of the species are enormously common. In general there is evidence to show that many birds winter in Africa far to the west of their Palaearctic breeding grounds, from which much diagonal passage of the Sahara is to be inferred.

The results are considered in relation to the ecological conditions on the northern and southern edges of the desert and in relation to the meteorological conditions over it. A remarkable circumstance is that few water‐birds indeed of any species have been observed in the oases of the Sahara,

so that their crossing of the desert is clearly very efficient, although so much of it is by lengthy diagonal and although many birds entering Africa in the middle longitudes meet with no suitable habitat between Europe and the tropics. Except perhaps for storks, which soar, and certainly for herons, which proceed by heavy flapping, the air speed of water‐birds is much greater than that of the small passerine migrants, the necessary potentiality of which has been calculated as 50–60 hours of flight without refuelling; but too little is known of the aerodynamics and physiology involved for it to be calculated whether water‐birds need to start with the comparable accumulations of fat and no definite information exists except for the Wood Sandpiper, which has been shown to put on up to 32% of fat. By comparison with passerines, more individual water‐bird species winter partly north and partly south of the Sahara; the factors affecting each bird's behaviour in this respect are unknown.
THE PALATE OF THE RED‐NECKED NIGHTJAR CAPRIMULGUSRUFICOLLIS WITH A DESCRIPTION OF A NEW FEATURE
Authors: Cowles Graham S.
Published: April 2008

The transpalatine canal and the associated vascular system of the palatine region in the Rednecked Nightjar Caprimulgus ruficollis is described. It is suggested that the specialized type of palate lining may be an adaptation for nocturnal aerial feeding.
SUMMER RECORDS FROM WEST‐SPITSBERGEN, 1964
Authors: Ogilvie M. A. , Taylor R. J. F.
Published: April 2008

An expedition studying geese spent six weeks in the summer of 1964 on the west coast of West‐Spitsbergen, Svalbard. The topography of the area is described. Observations were made on 28 species of birds and details of numbers and distribution are given for each. Counts were made over a period of a week of the numbers of Common Eider Somateria mollissima which began nesting in a small colony as the snow cleared from the ground. Weights and measurements were taken of Purple Sandpipers Calidris maritima and Glaucous Gulls Larus hyperboreus. One species new to Svalbard was seen, a Black‐headed Gull Larus ridibundus. Previously unrecorded breeding sites of Pink‐footed Geese Anser brachyrhynchus, and Barnacle Geese Branta leucopsis were found, and it is concluded that the further spread of the Barnacle Goose is probable. New sea‐bird colonies were also located.
TAXONOMY OF THE SOUTHERN AFRICAN ZOSTEROPS
Authors: Clancey P. A.
Published: April 2008

The four major groupings into which the Zosterops forms of southern African can be arranged have for long been treated by conservative systematists as constituting four discrete species (Z. capensis, Z. pallidus, Z. virens and Z. senegalensis).

In a major study, published in 1957, Moreau arrived at the tentative conclusion that in zoo‐geographical South Africa Z. cupensis and Z. wirens are clearly conspecific, Z. pallidus is a doubtful monotypic species, and Z. senegalais is a polytypic species of wide continental range, specifically segregated from the foregoing on the basis of a wingltail ratio character, and of juxtaposition without evidence of interbreeding.

A new study of the complex problem of Zosterops relationships in South Africa based on a critical study of over 900 specimens examined in the Durban Museum, suggests that only two species (Z. pallidus and Z. senegahsis), very closely related and part of the same superspecies, are actually involved.
DISTRIBUTION AND DISPERSAL OF CENTRAL PACIFIC LESSER FRIGATEBIRDS ‘FREGATA ARZEL*
Authors: Sibley Fred C. , Clapp Roger B.
Published: April 2008

During the period from March 1963 to July 1965 the Pacific Ocean Biological Survey Program made an extensive study of the islands of the Central Pacific in the area bounded by 10°N.,180° W., 10° S. and 150° W. In the course of this study much new information was obtained on the distribution and dispersal of the Lesser Frigatebird.

We have found that Lesser Frigatebirds are an abundant and widely distributed breeding bird in the Central Pacific, although only once previously reported breeding.

Most of the young Lesser Frigatebirds from the Phoenix Islands travel to the Solomon Islands, Bismarck Archipelago, New Guinea, or the Philippines. A few travel farther north to the Ryukyu Islands, Japan, Taiwan, and Siberia, and a few also move to areas southwest and southeast of the Phoenix Islands. Most of the dispersal to these latter areas apparently occurs earlier than the dispersal to the Solomons.

The dispersal pattern may be dependent in part on the surface wind pattern.
TERMS, STUDIES AND EXPERIMENTS ON THE PROBLEMS OF BIRD DISPERSION*
Authors: Berndt Rudolf , Sternberg Helmut
Published: April 2008

A terminology of the dispersion of birds, and of the ways in which it comes about, is proposed and explained. An examination of recoveries of ringed female Pied Flycatchers Ficedula hypoleuca show that many first breed a considerable distance from their birthplace, in contrast to the situation in the Blue Tit Parus caeruleus and Nuthatch Sitta europaea. The degree of such dispersion in these species, and presumably therefore the gene flow, is inversely correlated with the number of geographical races they contain. Results of experiments designed to investigate the types of dispersion mechanism occurring in F. hypoleuca indicate that both “dispersal” and “spacing” occur in birds of all ages, and that they are usually not oriented, but that the spacing of older birds which have not been constantly faithful to place usually leads to a previously known place.
THE BIRDS OF THE ALA DAGH MOUNTAINS, SOUTHERN TURKEY
Authors: Gaston A. J.
Published: April 2008

The paper lists the birds seen on visits to the Ala Dagh Mountains, Southern Turkey, in September 1965 and June 1966. It also describes observations made on bird behaviour in relation to the environment, and the avifauna of the area is compared with other mountain regions in the western Palaearctic.
A HIGH ALTITUDE HUMMINGBIRD ON THE VOLCANO COTOPAXI
Authors: Smith G. T. Corley
Published: April 2008

This paper sets out the results of fairly regular observation of Oreotrochilus chimborazo on Mt Cotopaxi between 1964 and 1967.

The species is found between 13,000 and 15,000 ft in a small area just south of the Equator where it nests on cliffs. Climate, terrain, food and nesting are described. Breeding continues throughout the year. Particular attention is given to the importance of nesting sites in this harsh climate and the consequent tendency towards colonial* nesting in favoured spots. The high degree of segregation between the sexes is also considered.

A brief account is given of the O. chimborazo population in the Guamani pass on the rim of the Amazon basin, where climate and terrain have produced some differences in breeding habits.
FOOD AS A FACTOR CONTROLLING THE BREEDING OF PUFFINVS LHERMINIERI
Authors: Harris M. P.
Published: April 2008

A study of Puffinus Iherminieri on Plaza Island, Galápagos, showed that, although eggs were laid in all months, there were marked peaks and troughs of laying. Intervals between successive layings varied with the success or failure of the first egg, an average of nine months for successful pairs, eight months for pairs which lost a young, and 6–5 months for those which failed to hatch an egg. However the breeding success did not influence the time between the end of one breeding attempt and the next laying. This suggests that birds were breeding as quickly as possible. The critical factor preventing more frequent breeding appeared to be the time required to replace the wing and tail feathers.

Details are given of the breeding biology, all aspects of which were strongly influenced by frequent and unpredictable food shortages. The average incubation period was 49 days but this was prolonged by temporary desertion due to food shortages. Chick growth and fledging periods (62 to 100 days) were variable. There was no well–defined desertion period and birds were experimentally induced to feed young for up to 120 days.

Overall nesting success was low (26%) and adult survival between breeding attempts was high (92–95%).

Food, planktonic fish larvae and Crustacea, appeared to be rarely abundant and details are given of the effect of food shortage on the breeding.

The breeding synchrony was brought about by food shortages. The ultimate factor controlling breeding appeared to be the availability of food for egg formation and there was no possibility of birds timing breeding so that young were being fed at a time of food abundance.

A comparison is made of the breeding of eight Puffinus species.
ADAPTIVE RADIATION IN ALCIDAE
Authors: Bédard Jean
Published: April 2008

Because of its homogeneity, both taxonomical and ecological, the sea‐bird family Alcidae constitutes an appropriate group for the study of adaptive radiation. This radiation involves mainly the acquisition of specialized feeding habits and the consequent specialization of the various species of the family at different trophic levels.

The plankton‐feeders, exemplified by the Least Auklet Aethia pusilla, have a relatively wide beak with a fleshy tongue and a broad palate with numerous denticles. The fish‐feeders, exemplified by the Razorbill Alca torda, have a narrow bill, a certain degree of tongue cornification and few, but sharp and regularly arranged palatal denticles. A few species, including the puffins and one auklet (Cyclorrhynchus), have characteristics intermediate between these extremes and feed partly on fish and partly on plankton.

Body‐size in the predator is related to the size of the prey and these relations are examined within the family. Within a group with similar adaptations, species which are alone in their niche in their area tend to be of intermediate body size for that group. Finally, though the family may exhibit a series of parallel trends in bill shape when the bill is considered as a social releaser, it exhibits a gradation in shape and structure (adaptive radiation) when considered as a food‐getting tool.
NOTES ON THE BIOLOGY AND ETHOLOGY OF THE NATAL ROBIN COSSYPHA NATALENSIS
Authors: Farkas Tibor
Published: April 2008

A preference for bushy evergreen undergrowth determines both the local and the general distribution of Cossypha natalensis. The lack of such undergrowth makes equatorial rain‐forests unsuitable. Tropical and subtropical evergreen forests provide excellent conditions from this point of view, and they are thus the main habitat type from which C. natalensis has secondarily extended into tropical and subtropical deciduous forests with evergreen undergrowth.

Adult birds remain in or close to their territories throughout the year. First‐year birds undertake longer movements during the winter. Breeding territories are relatively small, from 2,500 up to (exceptionally) 10,000 square yards (2,100‐8,400 sq. m).

Breeding begins in October. Both sexes build the nest, but only the female incubates. In southern Africa there is one brood a year, and the care of the offspring is protracted. The juvenile moult begins in the third and ends in the sixth month; adults have only one (post‐breeding) moult a year.

The begging behaviour of the young is somewhat different from that of most other turdine birds, and is considered to be more primitive. The ontogeny of the adult displays is described as observed in young birds kept in captivity.

The development of vocal behaviour is described. Special attention is given to the different functional forms of the song, and to two of its special features, imitation and a tonal quality termed vox humana.
GEOGRAPHIC VARIATION IN GENTOO PENGUINS PYGOSCELIS PAPUA
Authors: Stonehouse Bernard
Published: April 2008

Field and museum measurements confirm the existence of a morphologically distinct southern subspecies of Gentoo Penguin Pygoscelis papua ellsworthi, breeding on the Antarctic Peninsula and the South Orkney and South Shetland Islands. Morphological and zonal differences between other island stocks are noted, but present evidence does not support further definition of subspecies.
THE MOULT OF REMIGES AND RECTRICES IN GREAT BLACK‐BACKED GULLS LARUS MARZNUS AND GLAUCOUS GULLS L. HYPERBOREUS IN ICELAND
Authors: Ingolfsson Agnar
Published: April 2008

The moult of primaries, secondaries, and rectrices in two closely‐related gulls, the Great Black‐backed Gull Larus mavinus and the Glaucous Gull L. hyperboreus, was studied in Iceland. Both gulls moult their primaries in an extremely regular sequence, starting with the 1st (innermost) and ending with the 10th (oiltermost) feather. Usually two, less often one or three, primaries are growing per wing during the primary moult, which lasts for about six or seven months. Growlng primaries were estimated to lengthen on the average by 8.7 mm per day in marinus and 7.8 mm per day in hyperboreus.

The secondaries, usually 24 in number, are shed in two moult waves, one starting with the innermost feather soon after the start of the primary moult and then progressing slowly outwards, the other beginning with the outermost secondary after the primary moult is about half completed and then progressing rapidly inwards. The moult is completed just before the end of the primary moult as the two moult waves meet at about the 16th secondary. There are no marked differences between the two gulls in the moult of secondaries.

The moult of rectrices shows large variations in both species, some feathers being much more irregular than others in their time of shedding. In both species, indications of an obscured centrifugal pattern of replacement are seen, although the 5th (next to the outermost) rectrix is usually the last one to be shed. Significant differences were observed between the two species in the degree of regularity of shedding of some feathers and in the average position in the moulting sequence of others. The moult of rectrices starts soon after the moult of primaries is half completed. The feathers are then shed in rapid succession, and the moult is completed some time before the end of the primary moult.

The need for good powers of flight at all times is undoubtedly the reason for the protracted primary moult. This in turn causes the moult to start early, in adults sotnetimes before the eggs are laid; immatures moult even earlier than this. The rectrix moult and the main part of the secondary moult do not begin in adults until the young have fledged, but then progress very rapidly. Presumably, the loss of some of these feathers would impair the flying ability to an extent sufficient to make it difficult for the gulls to care for their young, while the rapid moult is necessary in order for the replacement of these feathers to be completed by the time the primary moult is over.
THE NOTATION OF BIRD‐SONG:A REVIEW AND A RECOMMENDATION
Authors: Hold Trevor
Published: April 2008

The reasons for a systematic form of notation of bird‐song are discussed. Though the sound spectrograph will remain the primary tool in any study of bird‐vocalization, there is still a need for a simple, comprehensive notation for the bird‐watcher. This will act as a supplement to the bird‐song recordings now available. After a survey of various attempts at bird‐notation, from syllabic notation to the sophisticated graph‐methods suggested by Stadler & Schmitt, A. A. Saunders and Gladys Page‐Wood, recommendations for a comprehensive notation are made, illustrated by notated examples of song‐phrases from the Nightingale.
A RINGING STUDY OF THE MIGRATORY BROWN SHRIKE IN WEST MALAYSIA
Authors: Medway Lord
Published: April 2008

Wintering Brown Shrikes frequent open lowland country, a habitat that is largely man‐made in Malaya. Individuals are sedentary during the winter season, each occupying a restricted area and exhibiting territorial behaviour.

The earliest observations each year in different parts of Southeast Asia indicate that the southward migratory journey is relatively rapid. In Malaya, migrants arrive from the first week of September to the third week of October. At a lowland netting station during 1964–68 a major part of the total catch was taken in the months of September and October. Only a small proportion of these early shrikes wintered in the netting area. No distant recoveries were reported, and the subsequent movements of birds that were not retrapped are unknown.

Shrikes netted in September—October comprised 29% adults, 54% full grown (i.e. immatures plus poorly—characterized adults), and 17% juveniles. The mean wing‐length was significantly longer among adults than among both other classes, which did not differ significantly. During the winter, all ages showed a progressive decline in wing‐length until the flight feathers were renewed in a premigratory moult falling in February—early April. Moult recorded in four Brown Shrikes taken in October‐November is interpreted as the completion of a post‐nuptial moult, commenced on the breeding grounds before autumn migration. In April, after the premigratory moult, confirmed adults constituted 70% of the total trapped and apparent immatures 30%.

The mean weight of September birds was lower than any other month except November. The low weight in November is partly correlated with the shorter mean wing‐length of the sample; it may also reflect the seasonally unfavourable weather of this month. The mean weight in February was high, although all birds were moulting; the weather in this month is typically hot and dry. Highest weights were recorded in April, indicating the premigratory deposition of fat. Weights of birds trapped more than once at different intervals showed a small initial weight loss (2 g), followed by a recovery within four days and no long‐term adverse effects. A comparison of September weights in Taiwan and Malaya provides a tentative basis for the calculation of fat reserves utilized on the migratory flight.

The proportion of returns after one year was 11%, and after two years 1 % only. Most returning birds were present in the netting area during the latter part of the winter of initial ringing; it is suggested tentatively that imprinting of the wintering grounds may occur during this period.

Ecologically in Malaya the Brown Shrike occupies a new habitat only gradually being filled by the resident Rufous‐backed Shrike. There is no evidence of interaction between the two species.
FAT, WATER, WEIGHTS AND WING‐LENGTHS OF AUTUMN MIGRANTS IN TRANSIT ON THE NORTHWEST COAST OF EGYPT*
Authors: Moreau R. E. , Dolp R. M.
Published: April 2008

Data are presented for the fat and water contents of 410 specimens of 11 species of trans‐Saharan migrants collected on the northwest coast of Egypt in autumn. Mean fat contents vary from 37% of lean dry weight in Hirundo rustica to 110% in Sylvia communis. There is also much variation in the range of fat contents within individual species, Muscicapa striata and Lanius collurio being exceptionally closely grouped and P. phoenicurus widely dispersed. The results for each species are discussed in relation to their migratory circumstances.

On the basis that the birds concerned would have started to cross the eastern Mediterranean with at least 11/2 times as much fat as they contained on landing in Egypt, comparisons are made with data for spring migrants in western Africa and with American trans‐Gulf migrants.

Water contents, discussed as % of lean dry weight, show considerable variation within each species:the coefficient correlating this percentage with % fat is around 0.50 except in Lanius (0.98) and Oriolus (0.92).

On investigating the relationship between wing‐length and lean dry weight, we did not find a strong correlation in any of the species and caution in accepting conclusions to the contrary is indicated.
ABNORMAL MIGRATION AND HYBRIDIZATION OF LARUS ARGENTATUS AND L. FUSCUS AFTER INTERSPECIES FOSTERING EXPERIMENTS
Authors: Harris M. P.
Published: April 2008

Between 1962 and 1966 eggs of Larus argentatus and L. fuscus were interchanged andalmost 900 young were reared by the wrong species. Many of these cross‐fostered young were later recovered or retrapped on and away from the colonies.

The British population of argentatus is sedentary and ringed birds are not recovered outside Britain, whereas fuscus normally migrates. Many cross‐fostered argentatus migrated to France, Spain and Portugal, areas where fuscus is common, but they did not migrate as far as the control fuscus. It is possible that these cross‐fostered argentatus had followed their foster parents when these migrated, but this is unlikely as the cross‐fostered fuscus also migrated although their foster parents would have remained in Britain.

Despite wide ecological and behavioural overlaps, interbreeding between L. argentatus and L.fuscus is exceedingly rare. However, as a result of cross‐fostering experiments, 31 and 40 mixed pairs were found on Skokholm in 1968 and 1969 respectively. Although some of the birds involved were unringed it is probable that all the adults in mixed pairs had been cross‐fostered. Other cross‐fostered birds were found mated with their own species and it appears that the sex of the imprinted birds was important. Female gulls will usually only mate with males of their own species, or in the case of the cross‐fostered birds, with males of their foster species. Males will mate with either species.

Evidence is given that suggests that the colour of the mantle and wings is important in species recognition at long range, and the colour of eye‐ring and join of the mandibles for recognition at short range. The role of voice is uncertain but general behaviour is probably unimportant.
GROWTH, AND ANNUAL CYCLES IN WEIGHTS, PLUMAGES AND REPRODUCTIVE ORGANS OF GOOSANDERS IN EASTERN CANADA
Authors: Erskine Anthony J.
Published: April 2008

A study of Goosanders, in connection with a Fisheries shooting programme on Cape Breton Island, has shown the pattern of growth in young birds, and of plumage and other annual cycles in fully grown birds. The plumage cycles show little difference between the sexes in the first year, with males thereafter moulting about one month earlier than females. Virtually no moult occurs from January to March, nor in adults during April to mid‐June, in this area. Weights and measurements permit ageing of flightless young of known sex, and sexing of all fully grown birds, but they do not distinguish first‐year from older individuals. Gross examination suggests that males in the second calendar year (11 to 12 months old) may come into reproductive condition, at least under conditions of year‐round hunting. Variations in annual moult cycles may be due to differing geographic origin of the birds; I suggest that birds killed in other Goosander shooting programmes should be used for comparative studies parallel to this one.
FOOD PREFERENCE AND THE EXTENT OF OVERLAP IN SOME INSECTIVOROUS BIRDS, WITH SPECIAL REFERENCE TO THE TYRANNIDAE
Authors: Hespenheide Henry A.
Published: April 2008

Analysis of published records of the food of flycatchers (Tyrannidae), swallows (Hirundinidae) and vireos (Vireonidae) of North America, and terns (Laridae) of the Pacific Ocean showed that size, rather than taxonomic, differences in food appear to be the most important ones for these birds. Although the distribution of insect sizes in nature approaches a two‐parameter log‐normal distribution, the distributions of the sizes of food items taken by birds show no significant differences from log‐normal.

Birds of a given feeding type (e.g. flycatchers) show a strong correlation of average prey size with bird body weight, and a significantly less strong correlation with bill characteristics, indicating that body size is a better predictor of prey size than any single bill character.

The slopes and/or intercepts of regressions of food size against body weight are different for birds of different foraging type.

Values of overlap in food preference are proportional to the similarity of the two species compared, expressed as the ratio of their weights.

Because insect taxa differ in size and because the amount of overlap in taxonomic composition of foods is therefore very roughly proportional to the amount of overlap in size, taxonomic differences in food may merely reflect differences in size preferences.

Values for overlap in food are greater than for most cases involving spatial niche parameters, indicating space is more easily divided than food, a conclusion supported by the relative rarity of large flycatchers.
EVOLUTIONARY ASPECTS OF FRUIT‐EATING BY BIRDS
Authors: Snow D. W.
Published: April 2008

In spite of a considerable literature on fruit‐eating, the general evolutionary implications of fruit as a source of food for birds have been neglected. A preliminary attempt is made to explore the evolutionary and ecological consequences of fruit‐eating, considered as a mutual interaction between parent plant and dispersal agent.

The relationship considered is that obtaining between fleshy fruits and the “legitimate” fruit‐eating birds which digest the fleshy part of the fruit and void the seed intact. Evolutionary aspects of seed‐eating are also briefly discussed.

The “strategies” adopted by fruits for dispersal by birds result in the production of abundant food supplies which are easy of access and exploitable by many species of birds. By contrast, the predation of birds on insects leads to a heterogeneous, sparse and cryptic food supply, to exploit which many different hunting techniques are necessary. Two important evolutionary developments in birds are attributed to these differences in food supply: there tend to be more species in families of insectivorous than of frugivorous birds, and lek behaviour in tropical forest has evolved in predominantly frugivorous birds.

The seasonal succession of fruits in temperate latitudes is discussed, and contrasted with the situation in the tropics, using examples from Europe and Trinidad. In general, the succession of ripe fruits in Europe seems to be adapted to the seasonal shifts of the bird populations, and the more nutritious fruits tend to have a more southerly distribution and to ripen later than the more succulent fruits. In the tropics the distinction between nutritious and succulent fruits seems to be largely one of habitat.

The constant succession of ripe fruits throughout the year in the tropics probably depends on competition for dispersal by frugivorous birds, which thus ensure the maintenance of their own food supply. This may be regarded as a symbiosis at the level of the ecosystem.
SEASONAL CHANGES IN THE ADRENAL STEROID TISSUE OF THE COMMON EIDER SOMATERIA MOLLISSIMA AND ITS RELATION TO ORGANIC METABOLISM IN NORMAL AND OIL‐POLLUTED BIRDS
Authors: Gorman Martyn L. , Milne Henry
Published: April 2008

The annual cycle of the interrenal (steroid secreting) tissue of the adrenal gland of the Common Eider is described in terms of its fractional volume and mean nuclear diameter. These measurements indicate a close relationship between interrenal activity and the organic metabolism of the bird throughout the year. High interrenal activity is generally accompanied by utilization of energy reserves, for example during incubation and by oil‐polluted birds, and low activity is associated with the replenishment of body tissues.

Heavy fat deposition in April, before egg‐laying, occurs at a time of increasing interrenal activity which apparently induces hyperphagia which in turn prevents the catabolic effects of high glucocorticoid production.

The significance of the annual interrenal cycle in relation to breeding and moulting is discussed for the Eider and compared with a variety of other species.
THE MIGRATION PATTERNS OF QUELEA QUELEA IN AFRICA
Authors: Ward Peter
Published: April 2008

Red‐billed Queleas migrate, at the beginning of the wet season, away from their dry‐season concentration areas and towards areas where rain started several weeks earlier. Considerable fat deposits are accumulated for this “early‐rains migration”.

The direction taken by the migrants, the distance they must fly, and the timing of the movement are dependent upon the timing of the rains and the way the rain‐front moves.

On the return “breeding migration” individuals in breeding condition stop to breed (in large aggregations) wherever they find conditions suitable for the founding of colonies. The location of the colonies can vary greatly from year to year.

The migrations performed by several populations, in different parts of Africa, are predicted on the basis of general rainfall patterns, and the predictions tested against the facts available.

There is evidence that individual females are able to produce a succession of broods in the same breeding season, at colonies which may be very far apart, and probably with different mates. The adaptive value of this “itinerant breeding” is discussed.

Many other bird species, which breed at a particular phase of the wet‐season/dry‐season cycle, are expected to perform similar “itinerant breeding”.
THE BREEDING OF COLLOCALIA GIGAS
Authors: Becking J. H.
Published: April 2008

The nest of Collocalia gigas is a solid cup with a shallow depression for the egg, constructed of plant material with moist cement. The main nest materials are living liverworts (Mastigophora and Herberta spp.) with green fern fronds or whole ferns (Hymenophyllaceae and Asplenium sp.) in the nest wall. Minor components are moss (Aerobryopsis, Ectropothecium and Meteorium spp.) and aerial roots of epiphytes (Orchidaceae).

Nests are always associated with falling water, being usually placed on ledges or in crevices behind or very close to waterfalls. Nests are single or in small colonies of up to ten nests.

The clutch consists of a single egg. Egg‐weight is 13‐7% of the adult's body‐weight, rather lower than in other Collocalia species.

In nest‐site and habits, and in some morphological characters there is a marked convergence, or a relationship, between C. gigas and the tropical American genus Cypseloides.