bluuebunny/crossref_metadata_2025 huggingface dataset:
THE NUMBERS AND DISTRIBUTION OF THE AFRICAN FISH EAGLE HALIAËTUS VOCIFER ON THE EASTERN SHORES OF LAKE ALBERT
Authors: Green J.
Published: April 2008

The numbers of Haliaëtus ‐vocifer on the eastern shores of Lake Albert were counted during September and October 1962. It is estimated that 167 eagles occupied 209 kilometres of shoreline. The local distribution of the eagle is governed by three main factors: the availability of perches, the shallowness of the water, and the proximity of a native fishing village. The amount of fish taken by these eagles is estimated to be under 0·4% of the weight taken by the native fisheries operating from the eastern shores of the lake.
DO BIRDS TRANSMIT FOOT AND MOUTH DISEASE?
Authors: Murton R. K.
Published: April 2008

Evidence regarding the role of birds in the transmission of foot and mouth disease is briefly reviewed.

Bird movements in Europe are briefly considered and while some autumn migrants and winter visitors to Britain could transmit disease to livestock on the east coast, it seems unlikely that summer migrants could be involved as vectors between France and the south coast.

Outbreaks of “obscure” origin tend to be concentrated in the eight coastal counties, Lincolnshire to Dorset. There is a correlation between the autumn outbreaks on the east coast (Lincolnshire‐Essex) and a high incidence of disease in the Low Countries and Denmark; and a correlation between a high level of infection in summer in France and outbreaks on the south coast (Kent‐Dorset).

Very few coastal outbreaks occurred in Britain at migration times during the war years of 1940–44 at a time when the level of Continental infection was apparently high.

Outbreaks in Britain in 1951–52 showed a clockwise movement from the east to the south coast paralleling the swing in the peak of infection from the Low Countries to France. During this period British outbreaks showed a marked tendency to be clustered round various seaports.

The relative importance and the volume of coastal infection has increased since the late 1930s and these facts cannot be reconciled with the bird transmission theory. The tendency for a later spread of the disease in Britain has lessened in recent years, presumably because control methods have improved.

The pattern of spread of disease within the Continent is also shown to be inconsistent with a theory involving birds as vectors. In Sweden the disease pattern has changed since Bullough (1942) examined the problem and it is very unlikely that bird movements have altered to account for this.

It is concluded on the evidence so far available that some explanation other than one incriminating birds is necessary to account for the incidence of foot and mouth outbreaks of “obscure” origin in the English coastal counties.
COLOUR PREFERENCE IN YOUNG ANATIDAE
Authors: Rear Janet
Published: April 2008

The young of 41 species of Anatidae, mainly from the Anserini, Tadornini, Anatini and Cairinini were tested for colour preference. For comparison, two species of gull, two of rails and three of pheasants were tested in the same experimental apparatus—a small closed box in which gelatine filter spots, red, orange, yellow, green, blue‐green and blue, could be placed before a source of indirect light.

A preference for green was general throughout the ducks and geese, and some species and individuals also pecked selectively at yellow. The tribes and genera differed in the extent of their avoidance of other colours; geese of the genus Branta and the sheldgeese tended to ignore blue, while Anser geese, the Anatini and Cairinini markedly ignored red and orange.

Members of the Phasianidae showed a similar preference for green. It was confirmed that gulls and the Moorhen, which normally peck at red on the adult's bill to obtain food, select red spots, as also does the Coot, although here the parent's bill is white.

It is concluded that there are certain broad correlations between feeding habit and the birds' unlearned colour preference in the pecking response, but more importantly, that closely related species tend to show similar preferences even when their food is quite different.
A COMPARATIVE STUDY OF CAPTIVE BLUE WAXBILLS (ESTRILDIDAE)
Authors: Goodwin Derek
Published: April 2008

The behaviour and voice of the blue waxbills Uraeginthus ongolensis, U. bengalus and U. cyunocephalus studied in captivity are described and composed. Most of the calls are homologous and similar, if not identical, but the songs and alarm calls of the three differ in sound. Feeding, agonistic and reproductive behaviour are described. Cyanocephalus bows its head further forward in the Stem Display, this difference being correlated with its blue crown. Minor differences of behaviour and the apparently less competent sexual recognition of angolensis may be correlated with its lesser degree of sexual dichromatism. The parental behaviour is essentially the same in all three forms. After fledging, young are recognized individually and strange young are not fed, except (rarely) by individuals with no young of their own. In three cases of adoption the common factor was that the adopting individual was sexually attracted to one of the real parents of the young. The taxonomy of the three species is briefly discussed.
THE VALIDITY OF SOME GENERA OF LARKS (ALAUDIDAE)
Authors: Harrison C. J. O.
Published: April 2008

The larks (Alaudidae) tend to be taxonomically arranged in a large number of small genera. There appear to be few characters which will separate the genera Alauda, Galerida and Lullula, and in recent times additional species have been placed in the first two genera without a reappraisal of the characters by which each genus is defined. Ten species are involved and originally these belonged to eight different genera.

In this group of ten species of eight genera as at present, six morphological generic characters are examined separately: the length of the tenth primary in relation to the roundness of the wing, the length of the hind claw, the profile of the crest, the conspicuousness of the superciliary stripe, the thickness and taper of the bill, and the length of tertiaries and secondaries.

All ten species show these characters, and the variation in any single character is fairly evenly graded through the group without marked discontinuity. The succession of species within the gradation varies from one character to another. It is not possible to find any group of characters which will subdivide the group of species.

Little is known of the behaviour of the ten species but examination of song‐flight suggests that such characters may also show a gradation without obvious subdivision.

It is considered that the present data do not justify the retention of the present genera for these species, and that it would be preferable to group them under the earliest generic name, Alauda.

The characters defining the Alauda group are listed and the relation of Chersophilus duponti to the group is discussed.
DISTRIBUTION, SYSTEMATICS, AND POLYMORPHISM OF THE AFRICAN WEAVER‐BIRD QUELEA QUELEA
Authors: Ward Peter
Published: April 2008

Quelea quelea is distributed throughout Africa south of the Sahara in the Grass Steppe, Dry Savanna, and Montane Grassland biomes. It is most numerous where its staple food–the seeds of annual grasses–is most plentiful. In all parts of the range, the males in nuptial plumage are dimorphic. Everywhere the “black—faced” morph is commoner, but with up to 25% of “white‐faced”. Proportions of the morphs are given for samples from various parts of Africa.

Only three races are accepted: quelea of western West Africa, aethiopica of the Sudan area, and lathami of southern Africa. In the Lake Chad basin there are hybrid swarms breeding (queleaj aethiopica), as there are in East Africa where aethiopica/lathami swarms occur.
THE DOMESTIC FOWL IN ANCIENT EGYPT
Authors: Coltherd J. B.
Published: April 2008

There is no recorded mention of the domestic fowl in Ancient Egypt before the Middle Kingdom (2134–1786 B.C.). Evidence for its existence there before this time is completely negative. The hieroglyph which is found in the earliest inscriptions, and certain peculiarities in the mention of the indeterminate birds, led some early writers to believe that the fowl had already been introduced into Ancient Egypt at the dawn of history, by invaders from Mesopotamia. The original of the hieroglyph however is almost certainly to be found in the Quail, and the wattled Sennar Guinea‐fowl may have been depicted on some of early representations.

There is evidence from the Indus Valley Civilization of the presence of the fowl there 2500–1500 B.C. A widespread trade appears to have existed between India and Mesopotamia as early as the Agade period (c. 2340–2180 b.c.), and there is strong evidence to show that the fowl was known in Mesopotamia (c. 2200 b.c.), introduced by the sea‐borne trade through the Persian Gulf, or by the longer and more dangerous caravan routes through what is now Baluchistan and Afghanistan. From Mesopotamia it probably found its way to Egypt by the land trade routes. The graffito of a cock was found on a Middle Kingdom temple dating to c. 1840 B.C., and another during excavation work on the tomb of Tut'ankhamon, dating 400 years later; while there is other evidence that during the XVIIIth Dynasty the cock was known in Egypt, such as in the Annals of King Thutmose III, where we have a reference to birds which bear each day, and a silver bowl of the reign of King Seti II (XIXth Dynasty) has a cock depicted on it. After this there is a long gap with no information, which may be explained in great part by internal decline, during which time trade suffered severely. During the Saite XXVIth Dynasty, which saw the beginning of a new period of expansion and revival, records re‐appear. Not, however, till the Persian Conquest do we find numerous mentions of its presence throughout the Empire. Writers of much later days tended to attribute the origin of the domestic fowl to the Persians, in so far as it appears to have been they who were responsible for its widespread dispersal in trade, in great part due to their excellent road‐building policy. The domestic fowl, however, fairly certainly came to Mesopotamia, and thence to Egypt, from India.
ADAPTATIONS TO NESTING HABITAT IN THE REPRODUCTIVE BEHAVIOUR OF THE BLACK‐BILLED GULL LARUS BULLERI
Authors: Beer C. G.
Published: April 2008

SUMMARY

The nesting habitats adopted by most colonies of Black‐billed Gulls Larus bulleri are river‐beds that are subject to flooding.

A number of respects in which the reproductive behaviour of Black‐billed Gulls differs from that of at least most other gulls, such as Black‐headed Gulls, can be viewed as adaptations, or byproducts of adaptations, to such nesting habitats:—

A different breeding site from the year before is often selected

The bulk of pair formation is accomplished before the gulls occupy their breeding sites; nesting territories are set up by mated pairs

In hostile encounters during the pair formation phase, site attachments are weak or transitory

In agonistic situations generally, attack thresholds appear to be relatively high, and fleeing thresholds relatively low

High intensity forms of“Choking” appear to be missing from the agonistic display repertoire

The growth of nest groups is rapid and orderly; nesting territories are small and the concentration of nests in the groups high

The time between occupation of the gullery site and the start of laying is short, and the synchrony of laying is high; this is probably related to the close proximity of the nests

The parents and young abandon the nest very soon after the egg hatch, and no “brood” nests are made

The young may develop locomotory powers more quickly than is the case in most other species; they can swim at an early age, and take to the water in tightly packed groups during alarms

The question of why these gulls should choose such vulnerable breeding sites is discussed.
THE BREEDING BIOLOGY. AND BEHAVIOUR OF THE DOUBLEBANDED COURSER RHZNOPTZLUS AFRZCANUS (TEMMINCK)
Authors: Maclean G. L.
Published: April 2008

In the southwestern part of the Kalahari region, the Double‐banded Courser Rhinoptilus africanus is restricted to stony terrain with low vegetation and good visibility. Nests are always exposed, usually on flat ground, less often in hollows or slopes, and seldom on rises. Sixty per cent of nests were among mammal droppings.

Nest relief is rapid and occurs every two hours or so; side‐throwing of small objects around the nest by the relieved bird is part of the ceremony. Incubation of the single egg takes about 26 days. The newly‐hatched chick is weak and is fed exclusively by the parents for the first few days. It can fly at about six weeks of age. Breeding seems to be continuous, regardless of weather and season.

The calls, displays, comfort movements and ritualized intention movements are described and analysed as far as possible. Adult coursers are subjected to an intense heat load in summer, and have a number of behavioural heat‐loss mechanisms which are described and discussed.

R. africanus and Cursorius rufus (both common coursers of the Kalahari) are briefly compared.
SPECIES ISOLATION BETWEEN THE HERRING GULL LARUS ARGENTATUS AND LESSER BUCK‐BACKED GULL L. FUSCUS
Authors: Brown R. G. B.
Published: April 2008

There is a large, mixed colony of the two “ring” species, the Herring Gull Larus argentatus and Lesser Black‐backed Gull L. fuscus, on Walney Island, northwest Lancashire. These birds are nesting at the very high density of one nest/40 square yards, or more, but although they defend their territories against both species indiscriminately, there is effectively no hybridization. This paper discusses the nature of the species isolation mechanism, and its function.

Since the two species can produce fertile hybrids, the mechanism must be of an ecological/behavioural nature, rather than morphological incompatibility. It is shown that there are slight differences in breeding season and habitat, but these do not seem to be great enough to account for the high degree of isolation.

It is likely that species isolation depends primarily on the female's choice of a mate. It is suggested that, as specific cues, she uses the differences in call‐note tones, and the colour of the back (and perhaps also of the eye‐ring), or both.

Herring Gulls and Lesser Black‐backs are adapted to slightly different niches. The overlap is so great, however, that any hybrid is unlikely to be at a disadvantage; but the overlap can only have arisen very recently, as a result of both species taking advantage of the increased availability of human refuse. It is possible that the isolation mechanism was evolved to cope with earlier conditions, when food was more limited, and the species' niches more sharply defined.
EXPERIMENTAL DEMONSTRATION OF A POST‐NUPTIAL REFRACTORY PERIOD IN THE TURTLE DOVE STREPTOPELIA TURTUR
Authors: Lofts B. , Murton R. K. , Westwood N. J.
Published: April 2008

Turtle Doves Streptopeliu turtur are shown to possess a typical post‐nuptial period of pituitary refractoriness; during this time the neuro‐endocrine apparatus is unresponsive to daylengths which at other seasons would result in gonad recrudescence. Males and females were collected in late summer when their gonads were regressing. Subjects were then held for 2.5 months on either 8‐hour or 17‐hour photoperiods by the end of which time their gonads had become uniformly fully regressed and inactive. All males were then given 3–5 months and females six months of exposure to 17‐hour photoperiods. Only the gonads of subjects pretreated with short days responded with gametogenesis.

All subjects (males and females) were moulting when caught and in addition had laid down heavy deposits of migratory fat by the half‐way stage of the experiment. However, further moulting and feather growth was inhibited in those birds kept throughout on long summer days and their fat deposits were maintained. In contrast, treatment with a period of short days enabled the subsequent completion of moult and new feather growth and the loss of migratory fat coincident with gonad development.

The results contrast with those obtained in previous experiments (Lofts, Murton & Westwood 1967) with the Woodpigeon, which lacks a refractory period. The reasons for the inter‐specific differences are discussed and some endocrinological implications of the results considered.
BIRDS OF RODRIGUEZ ISLAND (INDIAN OCEAN)
Authors: Gill Frank B.
Published: April 2008

A description is given of Rodriguez, the most remote of the Mascarene Islands, and of its avifauna, with special reference to the two surviving endemic land‐birds.
OBSERVATIONS AT A NEST OF THE CUCKOO‐ROLLER LEPTOSOMUS DISCOLOR
Authors: Forbes‐Watson A. D.
Published: April 2008

A nest‐cavity with two nestlings of Leptosomus discolor, found in the Comoro Islands in October 1965, are described. This is apparently the first time that nesting has been observed.

The nest was in a natural cavity in a tree growing in light secondary forest. Both nestlings still had traces of their original white down, even though they were nearly fully‐feathered. Apart from two thick tufts of white down on the hind‐crown, the plumage appeared very like that of the adult male.

Fragments of egg‐shell were found in the nest. They suggest that the original eggs were rather rounded, of a pale unmarked creamy‐buff, slightly glossed, measuring about 46 ± 5 ± 37 ± 5 mm.

During six hours observation at the nest the birds made five visits and brought six chameleons (no other food was seen). The female fed the young, but the male accompanied her. She did not enter the nest, except on one occasion. Details of this visit are given in full, being particularly remarkable for the tameness of the female.

The threat‐display of the young is described and possible predators mentioned.

Several calls are described, some apparently for the first time.

It seems likely that most prey is caught above ground‐level.

The evidence suggests that the birds are monogamous, not polyandrous as has been suggested.
SPRING MIGRATION THROUGH SOUTHEAST MOROCCO
Authors: Smith K. D.
Published: April 2008

Very few quantitative data existed for the spring migration of birds across the Sahara desert. Observations covering 105 days in spring 1963–66 were made at Defilia, on the extreme northern fringe of the desert in southeast Morocco. The physical features and climate of the area are described, with brief reference to neighbouring desert zones. The birds recorded are listed in weekly or part‐weekly totals, followed by subspecific and other comments on selected species.

The movements of migrants are summarized, together with the effects of adverse winds on migration; very bad weather along the northern desert fringe may contribute to the late arrival of some species in the British Isles (and presumably elsewhere in Europe) in spring by causing delays and heavy mortality. Most visible migration was northeastward or eastward, but substantial westward movements of hirundines took place.

Comparison is made with migration through other areas in Morocco and Algeria, both from existing literature and from previously unpublished data, which provide evidence of broad‐front migration across the entire width of the Moroccan Sahara. Birds recorded in northwest Algeria in 1966 are listed, together with notes on physical features, climate and field observations. Many terns and waders were recorded at Daiat Tchiour, including some predominantly coastal species, which suggests that the latter were migrating on a great‐circle track from winter quarters in West Africa across the Sahara to their breeding grounds in Siberia.

Recoveries of ringed birds are discussed; some of these, together with records of species well west of their normal migratory range, suggest that birds may be subject to lateral displacement by winds when crossing the Sahara, leading to considerable annual variation in species and numbers of birds recorded on the northern desert edge, even in the same place.
BREEDING SEASONS OF THE HOUSE SPARROW AND TREE SPARROW PASSER SPP. AT OXFORD
Authors: Seel D. C.
Published: April 2008

The breeding season of P. domesticus in 1961 and from 1963 to 1964. at Oxford began in April and ended in early August; that of P. montunus began slightly later and ended slightly earlier and this species also laid fewer clutches. In P. domesticus laying birds fell into two groups, namely “early‐” and “late‐starters”, which, from a comparison with data obtained from birds of known age, appeared to be mostly females two or more years old, and females one year old, respectively. In P. montanus, however, it appeared that birds of all ages were beginning breeding at about the same time in the season. The laying of first clutches of the early‐starting birds of P. domesticus and of the earlier starting members of the one group of P. montanus was correlated with the prevailing air temperature; it is estimated that P. domesticus began its laying at slightly lower air temperatures than P. montunus. It is suggested that laying is adapted to begin at a particular air temperature because at lower temperatures the adult would have insufficient energy available to produce and incubate a clutch.
A CHECK‐LIST OF THE BIRDS OF SABAH, BORNEO
Authors: Gore M. E. J.
Published: April 2008

A short account of the geography of Sabah, North Borneo, is followed by a survey of the main habitats and bird communities. The greater part of the paper is devoted to a check‐list of the birds of Sabah, which incorporates information collected since the standard work on Borneo by Smythies (1960). 504 species belonging to 65 families have been recorded.
FOOD, FEEDING RATES AND BODY TEMPERATURE IN THE NESTLING HOUSE SPARROW PASSER DOMESTICUS AT OXFORD
Authors: Seel D. C.
Published: April 2008

Diet, feeding frequency and body temperatures were studied in nestling House Sparrows at Oxford. In the diet, studied principally from crop contents, dipterous flies, caterpillars and aphids were most prominent in early May, early June and July respectively, while bread and dry grain, apparently less suitable foods, were more evenly distributed throughout the breeding season but apparently acquired an importance when insect foods were scarce.

Adult House Sparrows increased the frequency of their feeding visits to the nestlings proportionately with brood‐size for broods of 1–3, but for larger broods the feeding frequency did not increase. This abruptly achieved upper limit presumably gave rise to inadequate feeding of the larger broods (including the principal brood‐size). The male's share of the visits decreased markedly in the later stages of the nestling period, corresponding to his initiation of a display directed at the female. His displaying at this stage probably allows the female to begin a further clutch soon after the previous nesting has finished.

Nestlings were unable to maintain a steady body temperature above the ambient air temperature outside the nest before nestling day 10½. Maintenance of a steady body temperature depends on the nestling's feather covering, which is effectively complete at 9½ days. Before this, temperature control is possible within a limited range of ambient temperatures.
THE AVIAN ECOLOGY OF A TUSSOCK ISLAND IN THE FALKLAND ISLANDS
Authors: Woods R. W.
Published: April 2008

In the windswept and treeless Falkland Islands, the natural vegetation has been seriously depleted by two centuries of extractive farming. One habitat—mature Tussock‐grass—is of vital importance to the resident birds, and those Tussock‐covered islands that remain in a nearly natural state can support a far greater density and variety of bird species than any areas on the mainland.

Kidney Island maintains a diverse avian fauna because it offers abundant cover, nest‐sites, nest materials and food. In and around the dense mature Tussock‐grass which covers about 90% of the surface, 28 bird species nest on the island; 18 of them occupy one or other of the six minor habitats which can be distinguished in the Tussock‐grass. The nest‐sites and interrelationships of these breeding species are described.
TEMPORAL PATTERNS OF DUETTING IN AFRICAN BARBETS
Authors: Payne R. B. , Skinner N. J.
Published: April 2008

Four species of African barbets (Lybius torquatus, L. vieilloti, Trachyphonus darnaudii, and T. erythrocephalus) regularly sing in duet. Duets consist of phrases repeated at very regular intervals; in L. torquatus and L. vieilloti the standard deviation is less than a tenth of the mean interval between duet motifs. Sound spectrographic analysis of the songs indicates that an internal rhythmic behaviour pattern determines in large part the temporal features of the duet in these barbets:(1) one member of a pair of L. torquatus continues to call in rhythm even though its mate may call irregularly, (2) in the other three species the calling rhythm of each of the two mates is different, especially in L. vieilloti where the ratio of the periodicity of calling of the two birds averages 1:1.52 and where one bird continues to call at the same rate when its mate ceases to call, and (3) several non‐duetting African barbets have regular calling periodicities, some with greater precision than in the duetting barbets and some with less. In the barbets the temporal pattern of duets appears to be in greater degree determined by individual calling rhythms (as in some non‐duetting barbets) than by the auditory reaction time involved in a bird responding to its mate. Duetting in barbets probably functions both in maintenance of a pair bond and in territorial advertisement.
ON THE NATURE AND ORIGIN OF THE FEATHER COLOURATION IN THE GREAT WHITE PELICAN PELECANUS ONOCROTALUS ROSEUS IN ETHIOPIA
Authors: Baxter R. M. , Urban Emil K.
Published: April 2008

The yellow or orange‐brown colour on the breast feathers and to a lesser extent on other feathers of the Great White Pelican in a breeding colony on an island in Lake Shala, Ethiopia, is due to the presence of ferric oxide.

The feathers most probably become stained when the birds are in the water, and the source of the ferric oxide may be iron–rich silt carried into the lake by the Gidu River.
OBSERVATIONS ON THE BREEDING OF THE PINK‐BACKED PELICAN PELECANUS RUFESCENS
Authors: Burke V. E. M. , Brown L. H.
Published: April 2008

This paper summarises observations on the breeding behaviour of the Pink‐backed Pelican Pelecanus rufescens at Rakewa, Nyanza Province, Kenya, where the species has bred for at least 200 years. Observations covered most of one breeding season, November 1962 to April 1963.

Of at least 250 nests, 35 were closely observed. The community consisted of about 815 pelicans of which about 540 were adults. The death rate is estimated at 13% per annum and the mean life‐span at about seven and a half years.

The breeding site, in trees above a small swamp, is 15 miles from the favoured feeding ground. The colony is protected by local Luo people.

The pelicans feed and roost mainly at the Miriu Delta, 15 miles away, travelling between the two places so high up as to be unseen. They fish in the early morning, visiting the colony to feed young mainly between 09.00 and 13.00 hrs. Once the young are large both parents roost away from the colony at the Delta.

The breeding season takes place from August, towards the end of the rains, to March, at the end of the dry season. The birds breed in synchronised groups, the breeding cycle for any group occupying five months.

Nuptial display is performed on the nest trees, by single pairs or small groups. Two main displays are described, “pointing” and “bill‐clapping”. Mating occurs on the nest, with little preliminary display.

Nests are slight stick structures, repaired from year to year, and used by other pelicans if abandoned. The clutch is normally two eggs, occasionally three. Both sexes incubate, with infrequent change‐overs, for 33–35 days.

The chick is first brick‐red, becoming covered with white down. Feathers break through at about 12 days and have covered much of the body by 30 days. At 40 days chicks can recognise their own parent. They fly at 70–75 days.

Parents feed chicks by regurgitation, sometimes into the nest. They brood them closely at first, but after 10–12 days leave them much alone. Large chicks thrust the head far into the parental gullet, and injuries result from such feeding struggles. Feeding usually occurs before mid‐day, each parent normally delivering two feeds with a rest between. Curious convulsive movements of the young are probably begging displays.

Forty‐two young hatched in 35 nests, an average of 0.6 chicks/egg laid. The heaviest mortality among young occurred between 10–30 days when 31% of all chicks died. Young which flew were produced at the rate of 0.47/egg hatched, 0.28/egg laid, and 0.57/pair.
THE BREEDING BIOLOGY OF THE BLACK‐BELLIED STORM‐PETREL FREGETTA TROPICA
Authors: Beck J. R. , Brown D. W.
Published: April 2008

The breeding cycie and habits of the Black‐bellied Storm‐petrel are described from observations made over three seasons at Signy Island, South Orkney Islands. The species is strictly nocturnal on land and nests in stable scree slopes. With an estimated population of 100–200 pairs,Fregetta tropicais the rarest petrel breeding on the island.

In general, the breeding cycle ofF. tropicaresembles that ofOceanites oceanicus.Birds usually arrive from mid‐November onward and return to the same nest and mate in successive seasons. The female is absent from the nest for a week or more before the egg is laid, during which time the male continues to visit the site. From ten laying dates, egg laying appears normally to begin during the last week in December, but evidence is given that, in 1966‐67, laying was delayed by heavy winter snow build‐up coupled with a late melt. The egg comprises 26 % of the body weight of the female. Incubation is by both sexes in alternate spells of three days, the whole period lasting 38–44 days.

The chick is left alone in the nest by the parents almost immediately after hatching. Chick growth is described briefly and the effects of drift snow on development are discussed. The fledging periods of two chicks were 65 and 71 days, departure from the nest taking place in mid‐April.

Measurements of 36 Signy Island birds show considerable variability but are similar to those from other breeding localities.
THE SOCIAL BEHAVIOUR OF THE WHITE WAGTAIL MOTACILLA ALBA ALBA WINTERING IN ISRAEL
Authors: Zahavi Amotz
Published: April 2008

White Wagtails Motacilla alba wintering in Israel are partly territorial, mostly around human habitations, and partly live in flocks around temporary food sources. Individual birds may spend part of the season (or the day) in the territory and the other part with a flock.

Experiments with artificial distribution of food, in a natural habitat, brought about a change from flocking to territorial behaviour. Preliminary observations suggest that in the natural situation the pattern of food distribution may be the proximate factor which regulates the birds' behaviour, by determining whether they have to fight for their food.

Pairs are formed on many territories, and may last for long or short periods. Pair formation is initiated by females, who when seeking food appease the territorial males and are able to stay with them on their territories. Females also manifest territorial behaviour.

Although pairing in winter territories is similar, in the behaviour involved, to sexual pairing, it is very unlikely that winter pairing continues into, or influences, pairing for breeding. It is suggested that the function of winter pair formation is that it allows two birds to exploit one territory, and that the main advantage is to the female which is the subordinate bird of the pair. This kind of pair‐formation may be analogous to non‐breeding group territories reported in some other birds.
THE BREEDING OF CORY'S SHEARWATER CALONECTRIS DIOMEDEA ON THE SALVAGE ISLANDS
Authors: Zino P. A.
Published: April 2008

The breeding of Cory's Shearwater on Selvagem Grande was studied during the seasons of 1968 and 1969, on a number of specially timed visits.

After a pre‐laying exodus (duration not determined) the birds returned in a mass to the island on 26 May 1969 and laying began immediately reaching its peak on 31 May. Egg dimensions and weights are tabulated.

In most cases the female handed over to the male immediately after laying, and the two sexes incubated in alternating spells averaging about six days. The incubation period averaged 53‐8 days.

The chicks reached their maximum weight at about 53 days, but the fledging period was not determined. In 1968 young birds were leaving the nest on 22–25 October, about 90 days after the 1969 mean hatching date.

Herring Gulls were important egg predators, but losses of chicks were few, 29 out of a sample of 30 being alive at the age of about 60 days.
ASPECTS OF McCORMICK SKUA BREEDING BIOLOGY
Authors: Spellerberg Ian F.
Published: April 2008

The breeding behaviour of the McCormick Skua was studied at Cape Royds, Antarctica, for three summers. These observations followed the work of Young (1963a, b).

Records of banded birds suggest that at the age of five to six years birds return to breed in the area where they were reared. Breeding pairs retain the same territory and mate over consecutive summers. The male will retain a territory and remate if the female does not return, while there is some evidence to suggest that if the male is absent the female will leave the territory and remate elsewhere.

Unfavourable weather frequently forced incubating birds to desert their eggs and as a result some pairs laid three clutches (at the most two clutches of two eggs and a clutch of one).

The death of sibling chicks from fighting was examined by comparing the early growth of 11 successful pairs of chicks with that of 12 pairs in which one of the siblings died as a result of fighting. From a comparison of weights at hatching and the interval between the hatching of members of chick pairs, it appears that the difference in weight between twins and the gain in weight by one chick in the first few days is critical for the survival of the twins.

The breeding success, calculated from the total eggs laid and the total number of chicks fledging, was 40%, 42% and 17% for the three respective summers. Storms (periods of wind with snow) were the main factor influencing breeding success.
TAXONOMIC COMMENTS ON THE EURYLAIMIDAE
Authors: Olson Storks L.
Published: April 2008

On the basis of supposed differences in the shape of the spina externa of the sternum, the number of cervical vertebrae, the deep plantar tendons, the quadrato‐jugal articulation, and the size of the hallux, the Eurylaimidae were put in a separate suborder, the Eurylaimi. All of these characters are now shown to be variable within the family or shared with other suboscine families. It is recommended that the subordinal designation “Eurylaimi” be abandoned and that the family be included in the suborder Tyranni. A number of characters point to the Cotingidae as the nearest possible extant relatives of the Eurylaimidae. The Eurylaimidae consist of a number of unrelated genera with several relict species, and probably represent the remains of an ancient, once more widespread group that became isolated and gave rise to the suboscine fauna in South America while being largely replaced by oscines in the Old World. Recognition of subfamilies within the Eurylaimidae is discouraged. Smitkornis should be considered the most advanced of the eurylaimids. The sequence of suboscine families is discussed and a rearrangement is suggested.
THE ANNUAL RE‐OCCUPATION OF BREEDING SITES BY THE FULMAR
Authors: Coulson J. C. , Horobin Jean M.
Published: April 2008

The Fulmar has a long period at the breeding colony prior to egg‐laying. The pattern of annual occupation and build‐up in numbers has been examined in detail at Marsden, Co. Durham, at a colony in which over 100 eggs are laid annually (Order 3 of Fisher's classification).

The re‐occupation of the cliff starts in early November with an occasional visit by one or two birds. The main period of activity at the cliff is during the morning and, as the numbers build up, the diurnal period of occupation increases. By mid‐December the first birds to arrive in the colony do so before dawn and the last to leave remain well after dark until near midnight. Almost throughout the pre‐egg stage, the colony is deserted each night and re‐occupied the next day and birds only stay regularly overnight just before egg‐laying. A similar pattern of occupation occurs after breeding but in the reverse order.

The numbers of birds at the colony in January and February exceed the breeding population and include many non‐breeders. The non‐breeders progressively decline in numbers until May when only the breeding birds remain with a few non‐breeding birds.

The daily variation in the numbers of birds at the cliff is influenced by the wind speed. In general, the birds leave the colony under freshening conditions and the number present at the colony can be interpreted in terms of the wind conditions over the last three days.

It is suggested that the synchronised departures are primarily feeding trips, the birds using the strong winds to reach feeding areas, except that the departure just before egg‐laying is linked to egg development and synchronised laying in the colony.

Competition between Fulmars and Kittiwakes for nesting sites usually results in the Kittiwakes gaining the site. This is achieved by the Kittiwakes taking over the Fulmar sites during one of the latter's departures.
THE CONTAMINATION OF BIRDS' FEATHERS BY FUNGI
Authors: Pugh G. J. F.
Published: April 2008

Fungi have regularly been recorded on feathers removed from birds. Cellulose‐decomposing spores which are merely carried on the feathers were common on birds sampled in Britain, but were fewer than expected on the basis of random distribution on birds sampled in India. Hyaline‐spored fungi were less common on Indian birds, and more abundant on British birds than expected. Keratinophilic fungi, which are related to the dermatophytes, were particularly associated with related groups of birds: thus Turdus spp. regularly yielded Arthroderma curreyi, and partridges were contaminated with Ctenomyces serratus. Chrysosporium spp. were widespread on birds in India and Britain. Where associations have been shown, feather fats from these birds stimulate, or do not depress the growth of the keratinophilic fungi. Otherwise, feather fats were inhibitory to the fungi. The temperature relationships of the fungi, showing no growth at 40°C, would explain the restriction of the keratinophilic fungi to the outer, contour feathers, and of dermatophytes mainly to the non‐insulated parts of the birds' surface.
ON MULTIPLE BROODS AND THE BREEDING STRATEGY OF ARCTIC SANDERLINGS
Authors: Parmelee D. F. , Payne R. B.
Published: April 2008

Sanderlings on Bathurst Island in the Canadian arctic have two patterns of incubation. At some nests the eggs are covered soon after the fourth egg has been laid and at others incubation is delayed for 5–6 days. Because the delay is about the same time required to lay a second clutch and because a single individual alone incubates at any one nest, we suspected that Sanderlings might normally lay two clutches in a season, the male caring for one brood and the female for the other.

Histological and gross examination of the ovaries of two females taken as the birds began incubation showed eight freshly ovulated follicles in each female. The size gradation and histological appearance of the follicles indicated that two clutches of four eggs each had been laid within 8–10 days by a single female. The ovary of one female had additional large yolky follicles, suggesting a physiological capability of further ovulations.

Field conditions in the arctic summer are highly variable, and the small eggs and the rapid sequence of broods of Sanderlings may be breeding adaptations that permit them to multiply the traditional wader clutch of four eggs by 2 or 3 in favourable years. Selection for mating systems characterised by brief pair bonds and by polyandry is expected in precocial birds where some broods are incubated and cared for by the male, but further field work is required to determine the precise mating system of Sanderlings.
AN INVESTIGATION OF PHOTO‐REFRACTORINESS IN THE HOUSE SPARROW BY ARTIFICIAL PHOTOPERIODS
Authors: Murton R. K. , Westwood N. J.
Published: April 2008

The natural testis cycle and associated changes in bill colour of the House Sparrow Passer domesticus are described. Subjects were wild‐caught at three different times in the breeding cycles:in February when the testes were small and contained only spermatogonia, in May when they were fully recrudesced and contained bunches of spermatozoa and in late July at a time when spontaneous gonad regression was occurring as the birds entered their photo‐refractory phase. Each sample was divided into eight separate groups which were given a range of artificial asymmetric skeleton photo‐periods generalized as LD 6 +1/2:131/2; the 1/2‐h light pulse was given at a different point in the dark period in each group.

The birds entrained to skeleton schedules simulating complete photoperiods of up to 12 h duration as if the start of the long light pulse was dawn. However, with long‐day simulations (e.g. 6L 111/2 D 1/2 L 6D which simulates an 18 h photoperiod) the birds entrained to the start of the short light pulse to give an effective photoperiod of 121/2 h (that is, 1/2L 6D 6L 111/2D). The skeleton schedules simulating 14 h and 16 h were interpreted as such in February and were not effective in causing testicular induction, but they were apparently read as days of 161/2 h and 141/2 h in May, and as such maintained active spermatogenesis. The differences are discussed in terms of the changed frequency of a circadian oscillator. When birds captured in July were held on the various skeleton light schedules refractoriness was ended for most the subjects, as was proved by subsequently exposing them to a complete 16‐h photoperiod. Exceptions were the birds in the group given the 14‐h simulation, for these entrained as they had in May and so were effectively receiving a long 161/2‐h day. The discussion presents evidence to show that photoperiods in excess of 14 h cause the light sensitive phase of a circadian oscillator responsible for luteinizing hormone secretion to be phased into the non‐inductive period of darkness. Rehabilitation of the interstitial components of the testis is apparently inhibited in such circumstances.
DIALECTS AND GEOGRAPHICAL VARIATION IN THE SONG OF THE SPLENDID SUNBIRD NECTARINIA COCCINIGASTER
Authors: Grimes L. G.
Published: April 2008

The male Splendid Sunbird has only one song type, each note of which has a simple frequency/time profile. An analysis of the songs of males from several localities near Legon (5.63° N, 0.19° N) showed that there are clear‐cut song dialects characterizing each population. Those parts of the song giving rise to dialects are the time interval between consecutive pairs of notes (the time interval pattern) and the frequency/time profile of each note.

The dialects were preserved over a period of three years (the duration of the study) and there was little variation in the song of a ringed bird over a period of two months. The boundary between dialects is apparently quite sharp, occurring perhaps within a distance of 50 m.

Marked geographical variation in the song occurs, and is expected because of the mosaic of dialects that presumably exist throughout the sunbird's range in southern Ghana. For dialects to be effective in keeping populations together, those characteristics of the song which give rise to dialects should be readily and quickly discerned and need not require a statistical demonstration. This condition holds for the song of the Splendid Sunbird.

The results are compared with the ideas of Nottebohm (1964) and Thielcke (1969) on the maintenance and usefulness of song dialects.
Books
Authors: L. J. H.
Published: April 2008

Batten, L. et al. 1973. Birdwatchers' year. Pp. 351, 18 black and white photographs, numerous text‐figures. Berkhamsted

Clancey, P. A. 1971. A handlist of the birds of southern Moqambique

du Pont, J. E. 1971. Philippine birds

Farner, D. S. & King, J. R. (Eds) & Parkes, K. C. (Taxonomic editor). 1972

Tinbergen, N. 1973. The animal in its world

Wetmore, A. 1972. The birds of the Republic of Panami
LAKE RUDOLF AND THE PALAEARCTIC EXODUS FROM EAST AFRICA
Authors: Fry C. H. , Britton P. L. , Horne Jennifer F. M.
Published: April 2008

The 165 000 km2 sub‐desert corridor in which Lake Rudolf lies may affect the routes taken by Palaearctic migrants in eastern Africa. A five‐week study was made at Lake Rudolf during the spring migration period. The area is important for water birds, especially waders. It is less important for land birds, although on passage several passerines occur abundantly on Central Island, and some commonly in similarly well vegetated area (Turkwel river, littoral reedbeds). Some may fatten there before emigrating. Evidently the sub‐desert corridor is not so inhospitable that it is entirely avoided or overflown by migrants.
TRANS‐SAHARAN MIGRATION THROUGH SARIR, 1969–70
Authors: Hogg Peter
Published: April 2008

An account is given of observations made at the BP/Bunker Hunt Oil Production Centre at Sarir in the Libyan Sahara, on the passage of Palaearctic migrants in spring 1969 and 1970 and in part of autumn 1969. The ecological features and weather conditions in the study area are described. A map is given, and details of 70 species regularly observed are tabulated, with subsidiary notes on 57 other species only occasionally observed. A concentration of raptors, at a time when massed migrants were grounded, is described.

Some species not normally considered trans‐Saharan migrants turned up in Sarir, including Robin, Blackbird and Greenfinch; also Black‐headed Bunting and Rose‐coloured Starling, which normally migrate between Europe and India.
THE MOULT OF THE WHITE‐BACKED AND RÜPPELL'S GRIFFON VULTURES GYPS AFRICANUS AND G. RUEPPELLII
Authors: Houston D. C.
Published: April 2008

Moult is continuous throughout the life of the White‐backed Vulture and Rüppell's Griffon Vulture. Primary feather moult starts about 10 months after the bird leaves the nest, and the first feather to be shed is the innermost primary. From this position primary moult proceeds in an orderly sequence outwards towards the tip of the wing. Secondary feather replacement does not occur by the progression of moult waves, but by the irregular growth of feathers. It probably takes about 3 years of moult activity to complete the first feather replacement. Subsequent feather replacements occur by a slow but continuous process of feather replacement. Birds in adult plumage do show variations in the speed of moult, but this could not be related to breeding or body condition.