bluuebunny/crossref_metadata_2025 huggingface dataset:
AUTUMN OBSERVATIONS ON THE BOSPHORUS AND DARDANELLES.
Authors: Nisbet I. C. T. , Smout T. C.
Published: April 2008

Migration was studied in the Bosphorus‐Dardanelles area between 11 September and 1 October 1956. On most days observations were made at two or more places

 Daily counts of migration of soaring birds are given. Honey Buzzards Pernis apivorus crossed the Bosphorus on a front up to ten miles wide, and not more than a fifth or a tenth of the total could be seen from any one point. Some other species passed in narrower streams

 Different species of birds of prey passed to a large extent by different routes

 Moderate cross‐winds deflected the streams of soaring‐birds (especially eagles Aquila spp.) downwind

 Diurnal migrant passerines passed in large numbers through the western half of the area; the migration was on a broad front and often inconspicuous. In the Bosphorus area passerine migration was frequently towards the northwest

 Very large, fluctuating numbers of night‐migrants were seen along the Bosphorus, but fewer in the Dardanelles area

 It is thought that European Turkey is an important area of concentration for some northern passerine species

 Some water birds were seen following the Bosphorus southwards

 The apparent changes in the abundance of some of the migrant species over the centuries are discussed in an appendix
THE BREEDING OF THE LESSER FLAMINGO IN THE MWERU WANTIPA, NORTHERN RHODESIA.
Authors: Brown H. Dick
Published: April 2008

A hitherto unreported breeding site of the Lesser Flamingo Phoeniconaias minor is recorded in the Mweru Wantipa or Mweru Marsh, Northern Rhodesia. The site of the nesting colony, its structure, nest construction and behaviour of the birds is described. The importance of flooding in determining the site of the nesting colony is noted; adverse conditions caused by a rise in the water‐level of Lake Mweru Wantipa appear to have completely destroyed the nests. The instability of such environments does not offer much chance of regular and permanent breeding, and may influence local movements on the part of the birds.
FURTHER NOTES ON PAIRING AND SUBMISSIVE BEHAVIOUR OF THE RED‐LEGGED PARTRIDGE ALECTORIS RUFA
Authors: Goodwin Derek
Published: April 2008

1. The submissive display is described. It is sometimes given when the bird appears to be simultaneously frightened and attracted by a fellow member of the species.

2. The pairing behaviour of some individual captive birds is described. Some degree of mutual fear and hostility seems to be a necessary correlate of sexual attraction in this species. Birds that know and are at ease with one another do not pair.

3. A young male showed (in autumn) behaviour similar to that of a female ready to pair when introduced to an old and aggressive male. A possible biological function of such behaviour is suggested.
NOTES ON THE HABITS AND STRUCTURE OF THE GUACHARO STEATORNIS CARIPENSIS
Authors: Ingram Collingwood
Published: April 2008

1. Steatornis is peculiar, perhaps unique, among birds in possessing two specialized means, one auditory and the other tactile, of locating objects in total darkness.

2. Owing to the peculiar position of the hallux and the fact that the much‐abbreviated metatarsus is more or less on the same plane as the toes, the hind limbs are ill‐adapted for walking or for perching on a branch, but they afford the bird a secure foothold when resting longitudinally on a ledge.

3. In the embryo the abnormally short metatarsus is incorporated in the body of the foot. Although anatomically distinct in the adult, functionally it remains a part of the foot serving to support much of the bird's weight when resting in its normal crouching posture.
SUBDIVISIONS AND ZOOGEOGRAPHY OF THE GENUS TRERON (GREEN FRUIT‐PIGEONS)
Authors: Husain K. Z.
Published: April 2008

1. A new classification of the genus Treron is given using as many characters as possible.

2. A description of the genus as a natural group is given, and the subgroups recognised are described and discussed briefly.

3. The various possibilities of the distribution of the genus Treron and the derivation of the African group are discussed. The Oriental dry‐country form is closely related to the African group. The African group may have evolved from the Oriental dry‐country form or more likely from the Oriental evergreen‐forest form. In the latter case the Oriental dry‐country form T. phoenicoptera was presumably evolved from the northern African savanna form which entered India probably during the period from the late Miocene to the late Pliocene.
THE RELATION OF BIRD SONG TO MUSIC
Authors: Hartshorne Charles
Published: April 2008

Bird song is considered as a primitive form of music, and as an evolutionary anticipation of human music. Evidence is seen in the use of elementary musical devices: in the avoidance of mechanical regularity (principle of the “monotony threshold”): in the learning of songs and tunes: in the partial detachment from utility, and the playful cultivation of sound production: and, finally, in the tendency of species with more elaborate and, by our criteria, more “musical” songs to spend a larger fraction of the minute, day, and year singing (the “correlation of quantity with quality”). The best singers are those with more variety and complexity in the use of elementary musical devices.
AUTUMN MIGRATION IN SOUTHWEST PORTUGAL, 1957
Authors: Owen Jennifer
Published: April 2008

The Cape St. Vincent area of Portugal was visited in the period 23 August‐25 September 1957 in order to watch migration.

There was a marked movement of small passerine night‐migrants into and out of the area during the period, Whitethroats, Garden Warblers and Nightingales being the commonest species.

A mist‐net was used to catch birds sheltering in vegetation. The daily variation in the number of birds caught was considered indicative of the volume of migration the previous night, and the total bird population in a hedge of Pittosporum bushes was estimated on three days by the trap and retrap method.

Visible migration of hawks, larks, pipits, wagtails and Bee‐eaters was seen but not on a large scale.

Most birds left the Cape St. Vincent area in a south or southeast direction.

East winds, cloud and the conditions associated with a cold front inhibited migration, but there are always difficulties in correlating the weather and migration in an area such as this.

Further study of the area east and north of Cape St. Vincent would be interesting.
MAGENTA COLOUR IN FEATHERS: A PARALLELISM
Authors: Auber L.
Published: April 2008

The plumages of Nyctyornis amicta (Meropidae) and two species of Chlamydera (Ptilonorhynchidae) show markings of the uncommon magenta shade, apparently of “advertising” function.

In these markings, the Tyndall arrangements (otherwise causing non‐iridescent blue and related shades) are modified: the cloudy medium is underlaid, not by an opaque, but by a transparent, substratum. The shade, therefore, depends on media underlying this substratum.

In Chlamydera, the shade may vary considerably according to illumination, this being in agreement with Marshall's (1954) field observations.

Evolution of the complicated structures in both types of magenta feathers is discussed: they are analogous, but not homologous in all details. In Nyctyornis, they suggest relationship with Coliidae and Alcedinidae.
THE NESTING OF THE LITTLE PENGUIN EUDYPTULA MINOR
Authors: Warham John
Published: April 2008

1. The behaviour of the Little Penguin Eudyptula minor was observed at Cat Island, Bass Strait during the 1957/58 nesting season.

2. Although the birds have a number of natural enemies, man is probably the most serious destructive agent in this area at present.

3. The bird's repertoire includes contact notes and “songs”, the latter as an accompaniment to a variety of display postures.

4. During the stage when the chicks are guarded they are fed by the relieving adult soon after its arrival in the burrow, the young one's head being plunged into the parent's mouth. During “guard” and “post‐guard” stages the chicks studied were fed by only one adult bird although both might return to the nest.

5. The chicks begin to emerge after dark from their burrows at about 23 days old. One was deserted at 56 days and left for the sea at 60 days.

6. Display includes a variety of postures many of which seem analagous to those described by workers on some of the New Zealand and Antarctic penguins. A special dance precedes coition and trumpeting displays seem to serve for advertising territories and for threat. There is a welcome ceremony and ceremonial mutual preening.

7. Coition is frequent during the nesting period and recurs later when the penguins return to their burrows to moult.

8. Both old and young spend much time preening and collaborate in this activity.

9. Unemployed single birds were the first to moult. One breeding pair returned after 41 days post‐breeding sojourn at sea, completed the moult and returned there after 18 days without food.
NOTES ON AUTUMN MIGRATION IN GREECE AND CRETE
Authors: VAUGHAN RICHARD
Published: April 2008

Records are given of migrants seen in Greece and Crete 15 August‐13 September 1958. The most important notes are on Ardeidae, buzzards and shrikes.
A STUDY OF THE MALLOPHAGA OF BIRDS WITH PARTICULAR REFERENCE TO THEIR ECOLOGY
Authors: ASH J. S.
Published: April 2008

Over three thousand live birds have been examined in the British Isles and Sweden in a study of the ecology and biology of their ectoparasites. The main emphasis has been placed on Mallophaga, which are discussed in this paper.

The very exact food and temperature requirements of feather lice are considered.

The effect of lice on the host is discussed. Sick or injured birds which are unable to rid themselves easily of parasites tend to develop heavy infestations.

The relationship between host and parasite is described. The infestation of five common bird species is analysed on a specific and monthly basis. The proportion of birds carrying various species of lice varies from species to species and from month to month and also between sexes. There is a peak of infestation prior to the bird's breeding season. Rates of infestation on autumn migrants in Sweden are discussed.

Birds found uninfested and later found to be infested appear to acquire a parasite population at any season of the year.

The habitat of Mallophaga on their hosts is given for each species examined at Silwood Park, Berkshire.

The following points are discussed in appendices:–the collection and examination of birds, and an attempt to develop a satisfactory technique for sampling Mallophaga populations.
POPULATIONS OF TITS AND GOLDCRESTS AND THEIR FOOD SUPPLY IN PINE PLANTATIONS
Authors: GIBB JOHN A.
Published: April 2008

This paper describes a five‐year study in the pine plantations of Thetford Chase, East Anglia, to test the hypothesis that populations of tits (Paridae) and Goldcrests Regulus regulus are controlled by food shortage; and secondarily to assess the impact of bird predation on populations of forest insects.

 In winter, tits spend most of the day feeding; each bird examines some 1100 trees daily, and must find about 5 mg. dry weight of food, or 24 average‐sized insects, every minute of the day to maintain itself. Coal Tits Parus ater and Willow Tits P. montanus stored much food in spring and autumn; but stored foods formed a very small part of their diet. Interspecific segregation among the feeding birds was less marked than among the same species in broad‐leaved woods.

 The stock of invertebrate food in the pine foliage in winter ranged from 15–500 mg. dry weight per m2 of forest. The stock declined steeply during the winter, but increased again slightly in early spring. The level to which it fell in late winter was closely correlated with the mean air temperature at the time.

 In winter, the birds sometimes ate a substantial proportion of the available stock of food; in particular, they regularly ate about 50% of the stock of the eucosmid Ernarmonia conicolana (Heyl.), which was an important food of Blue Tits (Gibb 1958). The birds probably ate similar proportions of other suitable foods. Intraspecific competition for food was judged to be often severe.

 In winter, the birds' density was closely related to their stock of food. Coal Tits' survival from the end of the breeding season to the end of September was nearly constant from year to year, and was not correlated with the stock of food; but their survival from October to March was extremely variable and was closely correlated with the stock of food. This confirms that the population of tits was controlled by food shortage; nevertheless their territorial behaviour in autumn was probably also important.

 The paper ends with a discussion on the impact of bird predation on forest insects. It is concluded that as the birds eat a substantial proportion of the invertebrate stock in winter, they are at least a force to be reckoned with; also, if they help to stablise forest insect populations stepi should be taken to increase their numbers, perhaps most profitably by planting a variety of tree species to provide them with additional winter food.
BIRD NOTES FROM CHRISTMAS ISLAND, PACIFIC OCEAN
Authors: GALLAGHER M. D.
Published: April 2008

Christmas Island, Pacific Ocean, is described, with notes on the soil, climate and vegetation. Notes are given of 27 species of birds seen on the island during the period from June 1958 to June 1959. The total includes 17 sea‐birds, 2 resident land‐birds and 8 migrants. Breeding seasons vary greatly between species–all the year round, with or without peaks, and/or with variation between colonies; one restricted breeding season, or two restricted breeding seasons.
NEST‐SITE SELECTION AND COURTSHIP BEHAVIOUR OF THE BLUE TTT PARUS CAERULEUS
Authors: STOKES ALLEN W.
Published: April 2008

(1) A hole‐inspection display by male and female precedes nest selection. It serves to maintain the pair bond rather than show the hole to the female.

(2) Courtship includes moth flights and the dance. The dance has been modified from the head‐forward threat and combines attack, escape, and sex tendencies.

(3) The female dominates the male when the nest site is selected. This dominance counterbalances the male's more advanced sex tendency and permits mutual acceptance by the pair.

(4) Mutual wing shivering and fluffing of body feathers precedes copulation. Courtship feeding occurs from nest‐building through nestling stages.

(5) Great Tits dominate Blue Tits during selection of nest sites and may eject them from boxes already occupied.

(6) The bright plumage of the Blue Tit presumably evolved as enhancement of the head‐forward threat display and is only of secondary epigamic value.
TAXONOMY OF THE GENUS DUCULA
Authors: GOODWIN DEREK
Published: April 2008

This paper revises the genus Durula and discusses the affinities of some related genera. The genus Ducula is very close to Ptilinopus, D. poliocephala and its allies forming a connecting link between the two genera. The pied imperial pigeons are the most discrete group within Ducula. Ducula paulina and D. oenolhorax are treated as races of D. aena. There are indications that Lopho‐laimus and Hcmiphaga may be more closely related to each other than to Ducula. They are retained as monotypic genera. Drepanoptila and Alectroenas are offshots from Ptilinopus.
PROBLEMS OF HEAD‐SCRATCHING IN BIRDS
Authors: Simmons K. E. L.
Published: April 2008

Forms of head‐scratching are described and classified. Indirect‐scratching differs from the direct chiefly in that it involves the positive movements of lowering one wing and bringing the foot up over it. Both methods of scratching exist on two main levels: basic‐scratching is a reflex‐like response to irritation, etc., on the bill or head, while extended‐scratching functions as part of the feather‐maintenance system. Indirect‐scratching has been recorded as an apparent displacement‐activity in some species.

Possible evolutionary trends in head‐scratching are discussed. The two methods may have evolved independently from a more primitive method or successively one from the other. If the two methods evolved successively, then it is argued, contrary to the classical view of Heinroth, that indirect‐scratching evolved later than direct‐scratching, probably after, or concurrently with, the development of the extended function of scratching. Support is provided for this view by the distribution of indirect‐scratching in the bird‐kingdom and by the occasional use, by species in which indirect‐scratching is the rule, of a scratching method with some characters of the direct. The latter may be explained as either a reversion to the primitive method and/or the use of incomplete or wrongly co‐ordinated indirect movements. Variation in scratching within the avian family may be similarly explained and/or is due to incorrect taxonomy (e.g. in Parulidae and Timaliidae). As the method of scratching, generally speaking, is uniform in related birds up to at least the family level (in truly monophyletic groups), head‐scratching method is a potentially useful taxonomic character.

The scratching movements of a number of species are described and discussed, including the peculiar scratching of penguins, and a number of new records are given in the Appendix.
THE BIRDS OF THE COTO DOÑANA
Authors: Mountfort Guy , Ferguson‐Lees I. J.
Published: April 2008

The results obtained from three spring expeditions in 1952, 1956 and 1957 to the Coto Doñana, at the mouth of the Guadalquivir River in Spain, are described. A total of 210 species of birds was identified in the study area, including one new to Spain, the Masked Shrike Lanius nubicus, and one new to Europe, the Sand Lark Calandrella raytal. The effect of the severe drought of 1957 on the breeding of water‐dependent species is described. A number of resident and migrant species is shown to have undergone considerable changes in status in the area since the reports of Chapman (1893) and Jourdain (1936‐37). The report is divided into two sections: species found breeding or observed to be feeding regularly in the study area and those considered to be passage migrants or vagrants.
FALCO ELEONORAE
Authors: Vaughan Richard
Published: April 2008

The approximate totals for each part of the range may now be tabulated

(a) Northwest Africa 250 pairs

(b) Western Mediterranean 130

(c) Central Mediterranean 150

(d) Eastern Mediterranean

(i) Aegean Crete 850‐1,150 pairs

(ii) Cyprus 150–300

This gives a grand total of 1,550‐2,000 breeding pairs. Owing to the probable existence of undiscovered colonies not allowed for in the individual estimates, this total may be too small; on the other hand, many of the estimates for Aegean colonies were made fifty or more years ago, since when, on the analogy of the only two colonies in that area about whose history anything is known, there has probably been a decline in numbers. It should be remembered, too, that the size of many colonies has only been guessed. In spite of these uncertainties, however, I would suggest that the total world population of Eleonora's Falcons is under 4,000 birds, about half of which breed in the Aegean and Crete.

The most important areas where large colonies perhaps remain to be discovered are the Dodecanese and Algeria. Birds have been recorded in summer from the Tuscan Archipelago (Arrigoni degli Oddi & Damiani 1911, Moltoni 1954), the Ligurian Sea (Giglioli 1889), Pantelleria (Moltoni 1957 a), the Adriatic (Moltoni 1957 b), the Ionian Islands (Reiser 1905) and elsewhere (e.g. Provence, Leveque & Vuilleumier 1958, and even Central Spain, Lilford 1866), and, though most of these records are from the early part of the summer, it is possible that some of them represent hitherto undiscovered breeding populations. There was once a colony at Gibraltar, but this has long since ceased to exist (Bate 1928, on palaeolithic cave remains). Irby (1895) points out that the Rev. John White's “Hobbies”, which he says bred on the Rock, must have been Eleonora's Falcons and in the seventeenth century Eleonora's Falcon bred on the lies ?Hyeres (?Arcussia 1644: 60).

The known facts about Eleonora's Falcon are brought together, and contributions to existing knowledge made, under the headings Characters, General Habits, Food, Breeding, Breeding Distribution and Numbers, Migration, and Predation. It is shown that the breeding season is from mid‐July to October, that Eleonora's Falcon is a largely crepuscular feeder, that it is a summer visitor to its breeding haunts, and that it is dimorphic. The total world population is estimated to be rather less than 4,000 birds.
RECOVERIES OF RINGED GIANT PETRELS MACRONECTES GIGANTEUS
Authors: Tickell W. L. N. , Scotland C. D.
Published: April 2008

The ringing of Giant Petrels by F.I.D.S. parties in 1957‐58 and 1958‐59 is reviewed and the presence of a newly discovered rookery below the Antarctic Circle noted.

A comparative analysis is made of the numbers of recoveries received and the difference in their distribution amongst the southern continents during 1958 and 1959.

Details of 112 recoveries are given in an Appendix.
OWL VISION
Authors: Hocking B. , Mitchell B. L.
Published: April 2008

No evidence of important differences between the limit of red sensitivity in the Tawny Owl Strix aluco and in other birds or man could be found by measuring and observing pupil responses to change of intensity of illumination at this end of the spectrum. The gross structure of the eye and the rod/cone ratio both show extreme specialization of owl vision for a weak light. No behavioural evidence that the Tawny Owl could see mice by their own infra‐red radiation could be obtained.
SOCIAL BEHAVIOUR OF THE WHITE‐EYE ZOSTEROPS LATERALIS IN WINTER FLOCKS
Authors: KlKKAWA JlRO
Published: April 2008

1. In 1959 and 1960 observations on winter flocks of the White‐eye Zosterops lateralis were made at a feeding station and in an aviary at Dunedin, New Zealand.

2. Aggressive behaviour takes different patterns according to the intensity of aggression; ritualized pecking, threat display, incipient attack, combat and chasing are distinguished. Many components of the basic threat posture are similar to those of other passerine species, but “wing fluttering”, presentation of white underwing coverts and the brown colour on the flank, and “beak clattering” seem to be characteristic of the White‐eye. “Wing fluttering” is an incipient attack and often develops into an actual attack when stimulated by identical posturing by an opponent.

3. The pecking order found in the captive birds was a peck‐right hierarchy, but triangular relations were also observed when mated birds were involved. Prior residence was effective for a short period only and the despot in the prior occupants could be defeated by an aggressive intruder.

4. 710 birds were colour‐ringed at the feeding station, 306 returned and 204 were observed in aggressive encounters. The analysis of these encounters showed that in natural flocks dominant birds are engaged in aggressive encounters more frequently than subordinate birds, that dominants fight more often with birds of higher ranks, and that subordinates avoid encounters with aggressive birds.

5. A complex peck‐right hierarchy was found among members of different flocks visiting the feeding station. It is suggested that aggressive behaviour serves to establish and maintain the social hierarchy among individuals coming into contact over various objects. In crowded conditions severe fighting frequently takes place and the right of prior residence may be challenged constantly.

6. The importance of ecological implications of flocking and aggressive behaviour in the White‐eye population in New Zealand is discussed.
AUTUMN MIGRATION IN GREECE
Authors: Bateson P. P. G. , Nisbet I. C. T.
Published: April 2008

1. Two parties studied migration in several parts of Greece between 18 August and 11 September 1960.

2. Moon‐watching between 1 and 7 September revealed a large southward migration across both Northern and Southern Greece; also smaller groups of birds flying in directions centred around east, W.S.W. (only in Northern Greece) and N.N.E. (only in Southern Greece). The last two movements had not been suspected from previous observations. The species likely to be involved in these movements are discussed, but few conclusions can be drawn at present.

3. Resting night‐migrants were evenly distributed in woodland and scrub in many parts of Greece, but were nowhere very numerous. Woodland species were found in a wide variety of habitats. Willow Warblers were especially numerous at high altitudes in mountains. Several open‐country species (notably Rollers and Lesser Grey Shrikes) seemed much commoner in Northern Greece than in the South.

4. Some mountain birds had moved to lower altitudes by late August. Several forest species had moved up the mountain‐sides, well above the highest trees.

5. Little diurnal migration was seen.

6. Several waders appear to migrate through Greece much earlier than was previously recorded.
THE PECKING RESPONSE OF YOUNG WIDEAWAKE TERNSSTERNA FUSCATA
Authors: Cullen J. M.
Published: April 2008

The pecking of young Wideawake Terns was tested towards beak models of different colours (red, black, grey, white and silver) and towards a stuffed adult head with the normal black beak of the species. Of the colours, red and black received most pecks and the other colours somewhat fewer.

The strong response to black fits the idea that the chick's responsiveness is adapted to the parent's beak colour. It would not explain the equally strong preference for red which, it is suggested, is a relic of the days when ancestors of the Wideawake had red beaks.

It is argued that in other species, such as the Herring Gull, the evolution of the adult's beak colour may well have been guided by a pre‐existing predisposition of the chicks to peck more at certain colours, in other words the beak is adapted to the chick's colour responsiveness. Since the beak is important in social situations other than feeding the young, its colour may be a compromise between different selective forces, and this may be one reason that beak colours most effective for feeding the young are not always achieved.
THE AGGRESSIVE AND DISTRACTION BEHAVIOUR OF THE WESTERN SANDPIPER EREUNETES MAURI
Authors: Brown R. G. B.
Published: April 2008

The breeding biology and aggressive and distraction behaviour of the Western Sandpiper Ereunetes mauri are described from observations in the Hooper Bay area of Western Alaska during the summer of 1960.

The motivation of the distraction displays is analysed in detail, and it is concluded that the observed behaviour is the resultant of the attack and escape tendencies; the brooding tendency is not primarily involved. The function of the distraction displays is discussed in relation to human and other predators.
MIGRATION ACROSS THE SOUTHERN NORTH SEA STUDIED BY RADAR PART 3. MOVEMENTS IN JUNE AND JULY
Authors: Lack David
Published: April 2008

The only prominent migration over the southern North Sea in June and July is one westward of Lapwings. This occurred primarily with a wind between N.E. and S.E., occasionally with a light opposed wind, but it was visible only with an opposed wind. It occurred more often in anticyclonic than disturbed weather. It was equally frequent in the morning and evening, the evening movement normally starting two or three hours before sunset.

Other movements included a small eastward emigration, chiefly with westerly winds, the species being unknown, big S.W. immigrations of Black‐headed Gulls in late July, and small N.N.W. arrivals, perhaps of Starlings, in July.
TEMPORAL RELATIONS OF BROOD PATCH DEVELOPMENT IN DOMESTICATED CANARIES
Authors: Hinde R. A.
Published: April 2008

The development of the brood patch and other aspects of reproduction in domesticated canaries was assessed. Suboptimal breeding conditions ensured a considerable spread in the speed of reproductive development, and thus permitted an examination of the extent to which different aspects of development were related.

Loss of feathers is closely related to nest‐building, but not to egg‐laying.

Vascularization usually starts while defeathering is in progress.

Moderate vascularization (stage 3) occurs somewhat before egg‐laying, but only in birds which subsequently incubate.

Oedema occurs only in birds which incubate, and is closely correlated in time with egg‐laying.

Vascularity and oedema disappear a few days after the eggs are removed from an incubating bird.

The relationship of these findings to present knowledge of the hormonal control of reproductive development is indicated briefly.
TEMPERATURE REGULATION IN THE SOOTY TERN STERNA FUSCATA
Authors: Howell T. R. , Bartholomew G. A.
Published: April 2008

Temperatures of eggs, young and adults of the Sooty Tern were measured under a variety of environmental conditions on Midway Island.

The mean daytime body temperature of incubating adults (40·5° C.) was significantly higher than the mean (39·4° C.) for adults on nests at night.

The mean incubation patch temperature (39·‐6° C.) was significantly higher than the means for incubated eggs without visible embryos (34·8° C), incubated pipped eggs (36·6° C), or brooded, newly‐hatched chicks (38·3° C).

Severe heating by solar radiation is the principal environmental problem faced by nesting Sooty Terns. Shading by adults of eggs and young chicks prevents overheating; older chicks seek natural shade. When placed in the open sun, chicks of all ages can lose heat by vigorous panting. However, body temperature may rise almost to 45° C. and usually stabilizes in the lower range of prevailing black bulb temperatures.

The relationship of physiological and behavioural mechanisms of thermoregulation to environmental conditions during the terns' nesting season on Midway Island is discussed.
HEAD‐SCRATCHING IN THE PSITTACIFORMES
Authors: Brereton J. le Gay , Immelmann K.
Published: April 2008

The head‐scratching behaviour pattern is a valid taxonomic character. It supports the divisions within the Psittaciformes in the case of the Strigopinae, Nestorinae, Loriinae, and Kakatoeinae, but indicates that the Psittacinae are comprised of a number of groups. Some evolutionary problems arising out of the study of the scratching pattern are outlined.
THE ADELIE PENGUIN PYGOSCELIS ADELIAE AT CAPE ROYDS
Authors: Taylor Rowland H.
Published: April 2008

The Adelie Penguin rookery at Cape Royds, Ross Island, Antarctica, was kept under daily observation from 23 October 1959 to 26 February 1960.

The rookery is described and its history given. The total area used for nesting has remained much the same over the last 50 years, but there has been a marked shift of nesting colonies into more sheltered positions.

The adult population was counted every one or two days, and daily observations were made on 44 pairs of marked birds and 122 marked nests in which all eggs and chicks were individually marked.

Considerable fluctuations occur in the numbers of adults and nests at the rookery during the breeding season, and their effect on methods used for assessing rookery size from counts made at odd times is discussed.

Birds began to arrive at the rookery in mid‐October. The males usually arrived first and almost immediately began constructing nests. Eggs were laid during four weeks, from 4 November to 4 December; the usual clutch was two eggs, but in 65% of nests in which the first egg was lost soon after laying, a third was laid.

Measurements and weights are given for 75 eggs. There is a decrease in size of successive eggs laid. The average interval between the laying of eggs in any one clutch was just over three days.

The incubation period (day of laying to the day the chick finally emerged from the shell) of 150 eggs gave a mean period for first eggs of 34·8 (33–39) days, and for second eggs of 33·3 (30–37) days.

Parental routine during incubation in 35 pairs of known sex is described; very few females took first turn at incubating the eggs. The fasting periods for Cape Royds birds are compared with those at the South Orkney Islands.

The hatching, plumage, care and development of the chicks are described. The average length of the guard stage in 122 marked chicks was 22·4 days. The mean age of chicks when they left the rookery was 50·6 days; many chicks entered the water for short swims a day or so before they departed.

Of 600 adults that returned to moult at the rookery during February, probably two‐thirds were non‐breeding birds.

Mortality of adults at the breeding grounds was slight. Most egg losses were due to eggs being displaced from nests, or the abandoning of nests and eggs. A study of marked nests showed that 67% of all chick losses were directly due to Antarctic Skua predation, other mortality factors being desertion and exposure. Of the eggs 66% hatched and 75% of the chicks survived to leave for sea.

The breeding season at Cape Royds (77° 30′S.) is compared with that in the South Orkney Islands (61° S.). The availability of food is probably the most important factor determining the length of the breeding seasons at different rookeries.
VIVIPARITY AND AVIAN REPRODUCTION
Authors: Simkiss K.
Published: April 2008

A number of theories have been proposed to explain the absence of viviparity in birds, based upon considerations of weight and hormonal control in reproduction. It is here suggested that viviparity has not developed in birds owing to the unusual pattern of ovulation which they possess, and which would lead to a graduated series of developing embryos. To achieve viviparity it is suggested that birds would need to change their pattern of ovulation or be confined to producing only one offspring at a time.
MORTALITY AND FERTILITY OF EUROPEAN CHARADRII
Authors: Boyd Hugh
Published: April 2008

A review of published data on the mortality and fertility of 23 species of wading birds (Charadrii) breeding in or visiting western Europe.

Recoveries of ringed birds are the main source of estimates of mortality. In some cases recaptures of marked birds can also be employed. Apparent mortality in the first year after fledging is usually higher than in later years, though most estimates are probably biased by the preponderance of recoveries due to shooting. Adult mortality‐rates in stable populations vary from about 15·7% (Oystercatcher) to 51·9% (Common Snipe) with most in the range 30–45%. Closely related species tend to have similar mortality‐rates. There is a strong inverse correlation between death‐rate and body‐size, using wing‐length and weight as indices of size.

Studies of fertility are scarce and meagre, though. clutch‐sizes are adequately known. Few waders are double‐brooded, though many re‐nest if their first nest is destroyed. In most thriving breeding colonies, 66–96% of the eggs laid hatch. Survival of chicks from hatching to fledging, which is hard to measure, typically averages 40–80%, though success often varies widely from year to year.

Intensive long‐term studies of breeding groups make the most effective contribution to knowledge of population dynamics. For the many species for which breeding studies are likely to remain impracticable, studies of population composition in winter or on passage may provide useful substitutes, but only if techniques of sampling and of age‐ and sex‐classification can be improved.
PHOTOPERIOD AND THE REFRACTORY PERIOD OF REPRODUCTION IN AN EQUATORIAL BIRD, QUELEA QUELEA
Authors: Lofts B.
Published: April 2008

In a number of avian species in which testicular development can be evoked by increased daily photoperiods, it has been found that such development cannot be sustained indefinitely and that there is a period following each breeding cycle during which increased daily photoperiods are ineffective. This is the refractory period.

Gametogenesis ceases during this phase and its duration plays a critical role in the timing of the breeding cycles. The duration varies from species to species and in most temperate birds lasts some four months.

Some authors claim that the whole of the avian breeding cycle is under photoperiodic control and that the duration of the refractory period is determined by variations in daylength, short days dispersing it and long days prolonging it.

When the equatorial weaver finch, Quelea quelea, was placed under a 17‐hour daylength, the internal rhythm of reproduction was accelerated and the birds quickly passed into a premature refractory period.

During the refractory phase three weeks of short 8‐hour daylengths followed by a 17‐hour photoperiod had no effect on the duration of the refractory period, and birds displayed a recovery of spermatogenetic function at the same time as those maintained under a continuous 17‐hour photoperiod. In each case the refractory period lasted six weeks.

Birds maintained under an equatorial daylength of 12 hours also entered a refractory period and, again, pretreatment during the refractory period with shortened lengths of 11·25 hours had no effect on its duration.

Quelea which were maintained under a constant photoperiod of 11·25 hours during their refractory period showed a recrudescence of gametogenesis six weeks later, but under an 8–hour daylength the gonads remained regressed to the end of the experiment.

It was concluded that in this equatorial species a semi‐autonomous internal rhythm of reproduction operates and the refractory period is independent of photoperiodic fluctuations. There was no evidence of a premature dissipation of this period by a reduced photoperiod, nor was there a prolongation of refractoriness by long daylengths.
THE DISTRIBUTION OF BIRDS IN NORTHEAST GREECE IN SUMMER
Authors: Raines R. J.
Published: April 2008

The results of two expeditions to northeast Greece in May 1960 and 1961 are described together with records of a number of other parties of ornithologists who have recently visited the area. Observations include the first recorded breeding of Spur‐winged Plover Hoplopterus spinosus and Isabelline Wheatear Oenanthe isabellina in Greece, and of the Fan‐tailed Warbler Cisticola juncidis in north Greece; also the first recorded occurrence of Knot Calidris canutus and Spectacled Warbler Sylvia conspicillata in Greece. In the systematic list many discrepancies with previously published data are recorded for this relatively remote and ornithologically little known area of Greece. Observations are made on 111 species out of 219 recorded and on the migration observed.
MIGRATION ACROSS THE SOUTHERN NORTH SEA STUDIED BY RADAR PART 4. AUTUMN
Authors: Lack David
Published: April 2008

In autumn in Norfolk, the main nocturnal departures are (i) S.S.E., especially in September, of British summer residents; (ii) E., of unknown species; (iii, iv) S.S.W. and W., chiefly in October, the onward passage of birds, mainly thrushes, arriving in these directions from over the sea. Rarely, there are small northward movements. The main diurnal departures are (i) S.E., chiefly from mid‐September to mid‐October, of British summer residents; (ii) W., chiefly in October, the onward passage of diurnal migrants from Holland.

The main immigrations are (i) S.S.W. from Norway, chiefly of chats, warblers, flycatchers and arctic waders in September, and of thrushes in October; (ii) S.S.E. from northern Britain, chiefly in September, of British summer resident night‐migrants drifted off‐shore by westerly winds; (iii) W. by both day and night from Holland, mainly of Lapwings and small night‐migrants in September and of Starlings, Chaffinches, thrushes and Lapwings in October; (iv) both nocturnal and diurnal migrants heading W.S.W. from Denmark, when drifted south by northerly winds, of the same species as in (iii).

All 9 nocturnal and 4 diurnal movements analysed were far commoner and denser with following than opposed winds. They occurred with cross and opposed winds mainly when the wind was light. They tended to be commoner in clear than cloudy weather, and in anticyclonic than disturbed weather. After allowing for wind‐direction, they were equally common in warm and cold weather.

Small passerine night‐migrants leaving England S.S.E. must change their heading to southwest somewhere around the south of France. Arctic waders arriving S.S.W. must have changed their heading in Scandinavia from one much further to the west.

Norwegian thrushes change their heading from S.S.W. to S.S.E. when over the sea after dawn, provided that they have also been drifted by easterly winds, but they change back to S.S.W. over the land.
THE BEHAVIOUR OF THE WILLOW WARBLER PHYLLOSCOPUS TROCHILUS IN CONTINUOUS DAYLIGHT
Authors: Brown R. G. B.
Published: April 2008

Willow Warblers Phylloscopus trochilus at Wytham, Oxford (51° 46' N., 1° 15' W.), start to sing around sunrise, in late April to early June. In the continuous daylight at Neiden, East Finnmark (69° 42' N., 29° 25' E.), they do not sing all the time, but in late June to late July start singing between 22.45 and 01.45 hrs., the start becoming progressively later as the season draws on. At Neiden, nest visits start some time after song (01.00–02.30), and this is probably also true at Wytham.

The influence of environmental variables on the starts of the two cycles is discussed. It is concluded that song starts at Wytham when light intensity has risen above a certain threshold level, and at Neiden, when it has reached a minimum value or has started to rise again. It is suggested that the Neiden birds react to the closest approximation of their light intensity cycle to that at dawn further south. The end of daily song at Neiden may be controlled by internal factors. It is suggested that the start of the Neiden nest‐visit cycle is controlled by light intensity, but modified by temperature effects. The possibility that the environment affects the bird indirectly, via its brood or food, can be ruled out. The functional significance of the retention of activity lulls in the continuous daylight of the Arctic summer is discussed.

The daily song‐starts of the Garden Warbler Sylvia borin, Brambling Fringilla montifringilla, and Yellowhammer Emberiza citrinella, follow the same pattern as those of the Willow Warbler. The Redwing Turdus musicus often has no daily song lull; its nest‐visit lull begins and ends well before midnight. The significance of this is discussed.
THE BREEDING BEHAVIOUR OF THE SOUTH POLAR SKUA CATHARACTA MACCORMICKI
Authors: Young E. C.
Published: April 2008

At Cape Royds a small number of skua pairs nested at the penguin rookery and prevented other skuas from gaining any food there. Their territories were similar to those of the other pairs nesting near the rookery but which fed at sea. The birds occupied territories here from about mid‐November until early March.

The first eggs were laid on 27 November and most were laid by the second week of December. Most hatched after 28–29 days incubation and all hatched within a narrow range. Male and female alternated at the nest, sharing incubation fairly evenly. Nest changes occurred at intervals of 1 1/2–3 hours. In pairs feeding at sea, the female is fed by the male during incubation.

Chicks first flew when 49–59 days old but were fed by the parents for some time after this. Chicks fed on fish grew as rapidly as rookery chicks fed on penguin flesh, attained a heavier weight and grew more evenly. Length increase in primary feathers was a more useful index of growth than was gain in weight. It more nearly approached a linear relation with age and was not affected by fluctuations in feeding.

Desertion and over‐cooling accounted for most of the eggs lost.

Chick‐mortality fell within three categories: loss of the younger chick of the pair; loss of the older chick, or of a single chick after a period of slow growth“, loss of a single chick during normal growth. Most younger chicks were soon chased from the nest by the older chick and were killed later by cold or by adult skuas (a few were maintained by the parents for a short period away from the nest area). Only one pair reared two chicks to fledging; in other nests the older chick invariably survived longer. No chicks were lost on the territories after January.

Only a small number of adult birds in any colony killed chicks and even these were only active if confined to their territories, and not able to feed at sea, through bad weather. No parents were seen killing their chicks but some ate their chicks and may have first killed them. There were numerous instances of birds adopting chicks or not harrying them. Non‐breeding birds were not important predators.

The breeding success of pairs in different colonies varied from 0 to 38·5 % and averaged 23·2 % which is lower than that recorded in most other studies. Highest mortality was in territories outside colonies. This appeared to be correlated with a greater proportion of inexperienced birds in these situations. More chicks survived from rookery pairs than non‐rookery pairs. Feeding at the rookery allows both birds to be more often on the territory and there is less likelihood of food shortage during early chick‐rearing.

The loss of one chick of the pair is related to the low tolerance to starvation of the older chick: a temporary food shortage causes it to chase the other from the nest area.
A COMPARATIVE ANALYSIS OF NEST STRUCTURE IN THE WEAVER BIRDS (PLOCEINAE)
Authors: Crook John Hurrell
Published: April 2008

Ploceine nests are small globes with entrances at the side or below, with or without some extension into a spout or tube. The fabric of the nest is often remarkably strong and pliant.

Nine main variables of structure and construction in the nests of 62 species are listed and discussed. The paper includes the first account of the remarkable nest construction behaviour of Malimbus rubriceps in which nest material is “prepared” for use in building before the bird takes it to the nest.

Correlations are found between nest shape, materials used in construction, methods of attachment, stitching and fabric, and nest‐sites. The correlations reveal four fundamentally different modes (A‐D) of structural organization, divisible into nest‐types specialized to particular sites. A classification is provided.

The survival values of nest characteristics are analysed in relation to weather, predation and inter‐individual competition for materials. Fabric and lining are considered products of environmental selection, the stronger fabrics occurring in sites imposing greater stress. The roofing layer (which is correlated with tube loss) of many African colonial savannah birds is an adaptation to rain shedding. An alternative adaptation to rain occurs in Ploceus philippinus in India and consists in thickening the nest wall by excessive stitching on the exterior throughout nest occupation. This also correlates with the remarkable abilities of the species to repair its nest, in part an adaptation to the stealing of nest materials by neighbours.

The direction of evolutionary change in nest structure is considered. Shifts in type of nest‐site expose the structure to new interactions with environment and predation to which the resultant nest is an adaptive compromise. Discussion of the range of nests as a whole is complicated by cases of convergence and ignorance concerning the precise origin of the sub‐family. In general the strong fabric and suspended nest mark a major advance on the simple structure found in other Ploceidae. These features allow the adoption of sites providing additional security from predators. Modes A and D are held to be primitive; but while A has proved adaptable to many environmental circumstances and has given rise not only to four nest‐types but also to both Modes B and C., Mode D occurs only in a small group of birds successful within a restricted niche in Africa.