bluuebunny/crossref_metadata_2025_split huggingface dataset:
SUPPLEMENTARY NOTES ON THE BIOLOGY OF THE LARGE BIRDS OF PREY OF EMBU DISTRICT, KENYA COLONY.
Authors: Brown Leslie H. 
Published: April 2008

Summary.

The present paper is supplementary to that in ‘Ibis’ 94 and 95.
The fluctuations of population in an area of 146 square miles in Embu district, where a census of eagles was carried out in 1950, are described and discussed fur 951–52.
The inter‐relations of various species are discussed, particularly for Aquila wahlbergi and Lophaëtus occipitalis.
General accounts of breeding biology are given for Sagittarius serpentarius, Aquila wahlbergi, Hieraaëtus ayresi and Terathopius ecaudatus, and supplementary data for Aquila verreauxi, Hieraaëtus spilogaster, Polemaëtus bellicosus, Stephanoaëtus coronatus, Lophaëtus occipitalis, Circaëtus cinereus and Circaëtus pectoralis. These accounts are given under the following heads:—

General notes on adults.
Nests and nest‐building.
The incubation period.
The fledging period: (a) general, (b) development of the young, (c) parental behaviour, (d) food.
The post‐fledging period.

Special problems of breeding biology are discussed under the following heads: (1) Display; (2) Eagle‐weaver‐bird nesting‐associations; (3) Feeding rates of female and eaglet; (4) Breeding seasons; (5) Breeding success and replacement rate.
THE WINTER BREEDING SEASON OF LAND‐BIRDS IN EASTERN ERITREA
Authors: Smith K. D. 
Published: April 2008

SUMMARY.

The ecological conditions are described and breeding data are given for an area on the western shores of the Red Sea, where the annual rainfall comes in winter and most of the breeding takes place in winter and early spring.
A local population of Sphenorynchus abdimii does not migrate south in the autumn but breeds in eastern Eritrea in winter.
Comparison is drawn between the breeding season in eastern Kritrea and breeding seasons in other semi‐arid areas where data have been compiled, particularly central and western Eritrea, Darfur and Timbuktu‐Chad.
TERRITORY IN THE GREAT CRESTED GREBE PODICEPS CRISTATUS RE‐EXAMINED.
Authors: McCartan L. , Simmons K. E. L. 
Published: April 2008

Summary.This paper summarizes observations on territorial behaviour in the Great Crested Grebe in Oxfordshire and Berkshire and compares them with those of Venables & Lack (1934, 1936) in Surrey. On all waters, each breeding pair defended at least the immediate nest‐site but the area of the defended water adjoining this varied considerably. Such variation is probably affected by population density, distribution and availability of nest‐sites, the topography and the frontage of water before each nest‐site, as well as the degree of aggressiveness of individual pairs. The territories are taken up by already mated pairs and are often deserted when the young hatch, but a few pairs stay in the territory with the brood. More observation is needed on “colonialism” in the species because it appears to vary locally. Some possible functions of territorial behaviour are discussed but no definite conclusions can yet be drawn.
TERRITORY IN THE LITTLE RINGED PLOVER CHARADRIUS DUBIUS.
Authors: Simmons K. E. L. 
Published: April 2008

Summary.Comparisons are made between the territorial behaviour of a small population of Little Ringed Plovers near Reading, Berkshire, and Dutch birds (Sluiters 1938).Most birds arrived singly in spring, males preceding females from about 1–3 weeks as a rule, but some were already paired on arrival. Each pair, and also the few unpaired males, remained in territory more or less throughout their stay, defending it most intensely before egg‐laying and less afterwards. Locally, a good deal of feeding was done in the territory but in Holland only a little at best. The birds paired‐up, “courted” and incubated within the territory and most local plovers also remained there with the chicks. In Holland, many pairs deserted the territory for the feeding grounds after the hatch. This difference is linked with the feeding possibilities of the territory, usually good locally, where most territories had much surface water, but poor in Holland. Re‐directed territorial attacks (mainly aerial) are quite frequent against non‐related species. More significant, the Little Ringed Plover, the Ringed Ch. hiaticula and the Kentish Ch. alexandrinus regularly defend territories against each other.The only function of territorial behaviour at all obvious is that spacing‐out the available pairs of all three plover species present at any one site reduces the danger of a wide‐spread predation of the nests.
TERRITORY IN THE WREN TROGLODYTES TROGLODYTES.
Authors: Armstrong E. A. 
Published: April 2008

Summary.A brief outline of the male Wren's territorial activities is followed by a discussion of some points of special interest. Reference is made to the Wren's polygamous tendencies and the operation of sexual selection in this species. The territory of this highly territorial bird serves a variety of functions, including dispersal, pair‐formation, safeguarding reproductive activities and providing a foraging area. There is a correlation between food supply, activities connected with the territory and the character of the pair‐bond. Territorialism is considered to be basically concerned with reproduction and is regarded as an integrated set of activities in which vigour is the fundamental concept.
TERRITORY IN THE RED‐BACKED SHRIKE LANIUS COLLURIO.
Authors: Durango S. 
Published: April 2008

Summary.The essential requirements of Red‐backed Shrike territory in Sweden are described and the bird's procedure when establishing territory before the hen's arrival. The area varied from 1.4 to 8.3 acres on Faro, but elsewhere territories averaged as little as 1 acre. Bad weather often causes the territory to be abandoned at this stage.The behaviour after the arrival of the hen is described; a special feature is the cock's intolerance of nearly all birds except a hen shrike and a Barred Warbler.Reasons are given for thinking that the food‐function of the territory is important in this species.
THE TERRITORIAL BEHAVIOUR OF THE HAWFINCH COCCOTHRAUSTES COCCOTHRAUSTES.
Authors: Mountfort Guy 
Published: April 2008

Summary.The territorial behaviour of the Hawfinch Coccothraustes coccothraustes is examined. Some Hawfinches breed in small colonies, others in isolation. Pair formation takes place before the dispersal of the winter flock, following an unusually protracted courtship. Females are initially dominant and males learn to recognize them by their reactions to attempts to trespass beyond the normal limits of their “individual distance”. Copulation cannot take place in the flock because of interference by other individuals. Males then withdraw to take possession of the nest trees in the colony; these are temporarily defended from other males. Females later join the males and there follows a marked change in the behaviour between the sexes. Copulation takes place in the relative seclusion of the nest tree and its immediate surroundings. Individual territorial activity ceases completely once the eggs are laid and is replaced by communal territorial defence against predators.Solitarily breeding pairs, thought to be inexperienced birds, defend a small territory surrounding the nest for the whole of the nesting period. This area is insufficient to ensure an adequate food supply for the nestlings. Breeding success of solitary pairs is one third less than that of colonial pairs, because of restricted ability to defend the nest against predators. The establishment of breeding colonies is therefore assumed to have superior survival value.Song is shown to play an insignificant part in the breeding biology of the species.
BREEDING HABITS IN THE FAMILY MEGAPODIIDAE.
Authors: Frith H. J. 
Published: April 2008

Summary.

The ecology of the members of the family Megapodiidae is discussed.
The various types of mounds used in the incubation of the eggs are reviewed, and the methods used by the birds to maintain the egg temperature at the required level are described. It is pointed out that some very complicated methods of temperature regulation exist.
The breeding seasons are discussed, and it is postulated that the breeding season in Leipoa is limited by natural selection operating through food supply against the adults.
Clutch size is determined by the length of the breeding season.
THE AUTUMN AND WINTER MORTALITY OF STARLINGS STURNUS VULGARIS, IN RELATION TO THEIR FOOD SUPPLY
Authors: Dunnet G. M. 
Published: April 2008

Summary.

The food taken by Aberdeenshire Starlings during autumn and winter was investigated from stomach contents of samples shot regularly at roosts. The food available was known approximately.
During severe weather feeding habits of the Starlings change so that they become almost entirely dependent on man.
The gross weight and the fat‐deposits of the birds increased from autumn to mid‐winter and were not greatly affected by two snowy periods.
The period of most acute food‐shortage for the Starling may be the early autumn, after the leatherjackets have disappeared and before oats become available. At this time the total weight and the fat‐weight of adults and juveniles are low and the birds are moulting. Density‐governed mortality, which contributes importantly to stability of the breeding‐population density, may occur at this time.
FIELD NOTES ON BIRDS OF THE EASTERN SOLOMON ISLANDS
Authors: Cain A. J. , Galbraith I. C. J. 
Published: April 2008

Summary.

Field notes on the birds of Guadalcanal, San Cristobal, Ugi and Ulawa, based on the work of the Oxford University (Dept. of Zoology) Expedition to the eastern Solomons, are given. These include the first account of the behaviour and nesting habits of Aplonis brunneocapillus.
New records for the Solomons are Pelecanus conspicillatus (Guadalcanal), Egretta intermedia (San Cristobal, based on a specimen in the British Museum, Natural History), and Cichlornis whitneyi (Guadalcanal).
New records for islands in the Solomons (in addition to the above) are:—Guadalcanal: Cacomantis pyrrhophanus, Coracina caledonica, Turdus poliocephalus, Zoothera margaretae, Petroica multicolor.San Cristobal: Collocalia spodiopygia, C. vanikorensis.Ugi: Collocalia spodiopygia, Hirundo tahitica (others based as yet only on native reports are given for further investigation).
A revised list for Ugi, with rejection of some previous records, is given, also a short list of the birds of Ulawa (not investigated before) and a list of species from the Three Sisters, taken from specimens in the British Museum (Natural History).
THE BREEDING BIRDS OF BERMUDA.
Authors: Bourne W. R. P. 
Published: April 2008

Summary.

The Bermudas are a small group of oceanic islets 600 miles from land in the eastern North Atlantic. This paper is an attempt to define the unusual features of the ornithology based upon personal experience from 1940 to 1944 and a review of the literature.
Many lost migrants visit the group, but the resident community is restricted to roughly twenty species, all of which were once abundant. A hawk and several sea‐and water‐birds were exterminated after the islands were colonized in the seventeenth century; the present community includes reduced numbers of aix sea‐, four water‐, and ten land‐birds, of which four at least were introduced by man and others may be recent arrivals. The Barn Owl Tyto alba and the Common Tern Sterna hirundo have colonized the group since 1930. Several other introductions which were temporarily established have died out.
The smaller land‐birds are unusually abundant and exploit an unusually wide range of habitats in the absence of competition for food from related species. The numbers of the Bluebird Sialia sialis and possibly other species have fallen since the arrival of the House Sparrow Passer domesticus. Most birds are unusually tame, and show peculiarities of voice and behaviour; they nest unusually high in trees, and build large exposed nests. There are two good endemic races, Vireo griseus bermudianus and Pterodroma hasitata cahovi.
THE TAXONOMIC SIGNIFICANCE OF THE HEAD‐SCRATCHING METHODS OF BIRDS.
Authors: Simmons K. E. L. 
Published: April 2008

Summary.Birds scratch their heads in one only of two ways, either directly or indirectly, and one method is used by all members of the same family though not necessarily by all families in the same order. When related families have different head‐scratching methods, then the behaviour can help in disentangling difficult relationships. Examples are given. In the case of the passerines, only the Timaliidae (babblers) scratch directly. The implications are briefly discussed; for example, on this evidence Picathartes is not a babbler. The Psittaciformes are a potentially rewarding group for future work.
THE DISTRIBUTION OF STRUCTURAL COLOURS AND UNUSUAL PIGMENTS IN THE CLASS AVES.
Authors: Auber L. 
Published: April 2008

Summary.Structural colours in birds are surveyed systematically. From this survey, the common structural configurations in feathers, producing bright colours of the iridescent and non‐iridescent types respectively, are seen to exclude one anotherFeather pigments of unusual shades or chemical constitutions have been included in the survey, since some of them produce colour effects similar to structural colours of the non‐iridescent type
AUTUMN MIGRATION IN SOUTHWEST PORTUGAL.
Authors: Moreau R. E. , Monk J. F. 
Published: April 2008

Summary.During the latter half of September observations were made at various points on the coast of southwest Portugal. A great many migrants were seen, especially close to Cape St. Vincent, belonging to species that winter only south of the Sahara. Bird‐catchers were in evidence on the south coast, but not on the west. Evidence was obtained that migrants are fewest with east windsMost of the birds seen must have been travelling in a southwesterly direction for a long way and it is necessary for their survival that they should change course on reaching the shores of the Atlantic. Any that did not do so might find a temporary refuge on the Canary Islands, but the list of regular passage‐migrants there is very different from that of the birds seen commonly near Cape St. Vincent
THE BIRD SUCCESSION IN THE CONIFER PLANTATIONS ON MAT‐GRASS LAND IN SLOVAKIA (CSR).
Authors: Turc̄ek F. J. 
Published: April 2008

Summary.1. The species‐composition, number of individuals and biomass per one‐hectare are given. The three groups of areas studied were: (1) bare pastures, with an intermediate number of bird species, few individuals and high biomass of mainly carnivorous and insectivorous birds; (2) conifer plantations 1 to 5 years old, with the smallest number of bird species and the smallest biomass, but an intermediate number of individuals; (3) plantations six to twenty years old, with the highest number of both species and individuals of birds, but only intermediate biomass.2. The change from pasture to forest occurs about six to ten years after planting. The last forest birds come in about 20 years after planting.3. Birds have an important role in establishing the shrub layer and mixing some tree‐species into the plantation, by dissemination.4. Throughout the entire successional series the bird population seems to have a kernel of species, while other species come or go and/or change in density with the stages.
THE PUYA STANDS OF THE PERUVIAN HIGH PLATEAUX AS A BIRD HABITAT.*
Authors: Dorst Jean 
Published: April 2008

Summary.Field notes are given on birds living in a peculiar habitat of the Peruvian high plateaux, the Puya stands, studied in Southern Peru, near Azangaro, north of Lake Titicaca. These plants provide roost‐sites, feeding‐places and especially nest‐sites for the various species listed, but the sharp hooks on the leaves also cause the death of many birds, ranging from small passerines to Sparrow Hawks and Buzzards.A distraction display by the Black‐winged Spine‐tail is described.
FEEDING HABITS OF THE PALM‐NUT VULTURE GYPOHEERAX.
Authors: Thomson A. Landsborough , Moreau R. E. 
Published: April 2008

Summary.The literature on the food of Gypohierax is reviewed. First‐hand evidence of the bird's catching live fish in the Gambia is cited. Up‐to‐date information is given about the ecology of the bird in East Africa, with particular reference to its occurrence in the absence of oil‐palms and its eating Raffia fruit. On the basis of this and of the survival of Gypohierax in zoos, it is concluded that the vitamin‐rich oil‐palm fruit is not essential to the bird; but one that had been in captivity for 11 years, when presented with the fruit, preferred that to its usual meat.
THE INTERSTITIAL AND SPERMATOGENETIC TISSUE OF AUTUMN MIGRANTS IN SOUTHERN ENGLAND.
Authors: Marshall B. Lofts & A. J. 
Published: April 2008

Summary.1. Of 17 adult males of nine species of southbound migrants that were accidentally killed at about the point of departure from Southern Britain in autumn, all possessed an interetitium in the process of post‐nuptial rehabilitation (involving cholesterol production) even though they were flying away from the traditional breeding ground. Varying amounts of cholesterol‐positive material still lingered in the tubules.2. Of 11 juvenile males of seven species similarly collected only six individuals possessed an interatitium in which had already developed cholesterol. One adult Redwing showed pronounced signs of autumnal sexuality in the production of a few primary spermatocytes.3. Cholesterol is almost certainly the precursor of the steroid hormones; and its early conversion into androgens in “stationary” species is probably responsible for the widespread autumnal sexual behaviour that occasionally culminates in “out‐of‐season” reproduction. Its presence in adult migrants probably explains the recrudescence in sexual behaviour that occurs in certain species just before their departure from the breeding grounds. In migrants, however, unlike “stationary” species, this capacity to display is extinguished by the more powerful (in them) inherent urge to migrate.4. Southbound, as well as northbound, migrants possess subcutaneous and subperitoneal fat‐deposits. The physiological basis for the production of this material is discussed briefly, and a possible additional function for such fat is mentioned.
THE DISPLAY OF THE MANAKIN M. MANACUS
Authors: Darnton Iris 
Published: April 2008

SummaryThe “dancing rings” of Maracus m. trinitatus are almost invariably constructed in small clearings on the forest floor so that whippy saplings grow from their edges to form spring boards as the manakins ricochet back and forth across the rings.Four sounds are made by both sexes, the snap, the “comb” noise, the growling “grrrrt” and the whirring wings. There is no satisfactory explanation of how these sounds are produced.Apart from casual visits, the hens suddenly all appear at about the same time during the morning to dance with the cocks—one hen to a ring. The only exception to this was a pair that spent most of the day together at their ring.Usually at about 9.30 a.m., all the cocks had drifted away, and then nearly every ring was occupied by a hen, dancing back and forth and producing, although not quite as loudly, the same sounds as produced by the cocks.During the period the manakins were under observation (11 February to 16 March), no quarrelling took place among the cocks although their rings were often less than a foot apart; nor were the hens pursued or mated when they danced with the males. This probably indicates that the pairs using the dance rings were already mated or even with nests.
VISIBLE MIGRATION IN THE EAST BALTIC AREA
Authors: Kumari Erik 
Published: April 2008

SUMMARYBird migration in the East Baltic area is characterised by the facts that the spring and autumn flights vary considerably in intensity; and that there are marked differences in the species represented in the southern and northern parts of the area. In the region of Courland Bay the large bulk of the migrants is made up of passerines (mainly finches); whereas the migration along the Estonian coasts is dominated by the waterfowl, in particular various species of diving ducks and divers. In both spring and autumn the Long‐tailed duck and Common Scoter traverse the straits of West Estonia and the Gulf of Finland in huge masses. During recent years the systematic investigation of visible migration in the East Baltic area has been begun, while all researches are now organised and coordinated by the Baltic Commission for the Study of Bird Migration.
AUTUMN IMMIGRATION OF REDWINGS TURDUS MUSICUS INTO FAIR ISLE
Authors: Williamson Kenneth 
Published: April 2008

SUMMARYThe meteorological conditions governing autumn immigration of the Continental and Iceland races of the Redwing, Turdus m. musicus and T. m. coburni, are compared.The pattern of immigration in a normal year is outlined. Continental Redwings usually appear at Fair Isle with easterly or southeast winds, most abundantly at the end of the first week of October, while small numbers of Iceland birds generally arrive during the same month with cyclonic westerly or northwesterly weather, and form 20–25 per cent of the Redwings trapped.An unusually large invasion of Iceland Redwings in October 1956 seems likely to have been due to special weather factors in the northeast Atlantic rather than to a population peak following exceptional breeding success.The 1956 autumn passage of both races at Fair Isle is summarised.The biggest “broad‐front” invasions by Continental Redwings are associated with anticyclones over Scandinavia when their easterly airflow covers the North Sea, but influxes on a lesser and more localised scale also take place with high pressure over Scandinavia and low‐pressure developments bringing pre‐frontal easterly winds to the North Sea.Direct passage from western Norway to Shetland has been recorded with ridge and col weather over the route, and along the east coast of Britain with cols in the North Sea, but the numbers concerned in the Shetland area are small. The influence of calms, light airs and clear skies (properties of col and anticyclonic weather) on the migration of the Continental race is paramount.Some Iceland Redwings arrive with anticyclonic weather over the northeast Atlantic and a following wind, and “onward passage” of both races from Faeroe‐Shetland is witnessed with col or anticyclonic weather over the “inter‐islands” route. Most movements of coburni, however, have a background of cyclonic westerly or northwesterly weather and are best interpreted as downwind drift.It is argued that if the two races respond alike to weather at the time of departure and during the course of the journey, then certain of these movements (and in particular the big waves of October 1956) must originate in southern Greenland, the flocks having previously crossed Denmark Strait from Iceland in clear weather with light easterly winds.
ROOSTING MOVEMENTS OF BIRDS AND MIGRATION DEPARTURES FROM ROOSTS AS SEEN BY RADAR
Authors: Harper W. G. 
Published: April 2008

Summary.Unusual radar echoes attributable to the roosting movements of large flocks of birds, and to departures from roosts on migration flight are illustrated. Probably the most striking displays are received from Starlings Sturnus vulgaris. Radar evidence is shown of a much more rapid break‐up of flocks on migration at night than by day. Weather at departure points is studied.