Sexual dimorphism of acoustic signals in the oriental white stork: non-invasive identification of sex in birds

Identification of the sex of birds is important for captive breeding of endangered species. In the oriental white stork (Ciconia boyciana), an endangered species, both sexes produce an acoustic signal called "clatter" by rattling their mandibles together to generate sounds. We examined the structure of male and female clatter to determine whether clatter is sexually dimorphic. The acoustic structure of the clatter of the two sexes proved to be dimorphic with respect to the fundamental frequency; female clatter had higher fundamental frequencies. The fundamental frequency correlated significantly and positively with bill length, suggesting that bill morphology contributes to the sexual dimorphism of clatter. Sexing can be done by acoustic signals without capturing birds, and thus is useful as a non-invasive sexing method for ecological and conservation studies of birds.     

Development of the testes in female domestic fowls submitted to an experimental sex reversal during embryonic life

The sex differentiation of the female chick embryo can be totally inverted toward the male sex by an early extraembryonic testis grafting. This sex reversal remains permanent, as shown by three adult fowls described in this paper. They possess two testes associated with normally differentiated male excretory ducts and their Müllerian ducts have regressed. The development of male sex characteristics such as external features, behavior and complete spermatogenesis is evidence that these cocks have endocrine and exocrine capabilities similar to those of normal cocks. Although these cocks were able to mate with female fowls, they were sterile. A mechanism is discussed by which grafted testes induce such modifications in females. Hypotheses considering the heterogametic sex (female in birds) as exerting a dominant influence on the phenotypic sexual differentiation can be discarded in light of our results because a homogametic testis provokes the definitive sex inversion of a female.     

The evolution of sexually dimorphic tail feathers is not associated with tail skeleton dimorphism

Sexual selection can influence the evolution of sexually dimorphic exaggerated display structures. Herein, we explore whether such costly ornamental integumentary structures evolve independently or if they are correlated with phenotypic change in the associated skeletal system. In birds, elongate tail feathers have frequently evolved in males and are beneficial as intraspecific display structures but impart a locomotor/energetic cost. Using the sexually dimorphic tail feathers of several passeriform species as a model system, we test the hypothesis that taxa with sexually dimorphic tail feathers also exhibit sexual dimorphism in the caudal skeleton that supports the muscles and integument of the tail apparatus. Caudal skeletal morphology is quantified using both geometric morphometrics and linear morphometrics across four sexually dimorphic passeriform species and four closely related monomorphic species. Sexual dimorphism is assessed using permutational MANOVA. Sexual dimorphism in caudal skeletal morphology is found only in those taxa that exhibit active functional differences in tail use between males and females. Thus, dimorphism in tail feather length is not necessarily correlated with the evolution of caudal skeletal dimorphism. Sexual selection is sufficient to generate phenotypic divergence in integumentary display structures between the sexes, but these change are not reflected in the underlying caudal skeleton. This suggests that caudal feathers and bones evolve semi‐independently from one another and evolve at different rates in response to different types of selective pressures.     

Display behavior of three troops of Japanese monkeys (Macaca fuscata)

In this paper the display (i.e., “branch-shaking”) behavior of three troops of Japanese monkeys—the confined Oregon troop as reported byModahl andEaton (1977), the semi-free-ranging Arashiyama West troop and the free-ranging Arashiyama B troop—are compared. The comparison reveals several similarities and dissimilarities between the Oregon troop and the two genetically related Arashiyama troops. The similarities include three display postures (shaking, kicking and leaping) and an increased frequency of male but not female displaying during the breeding season. The dissimilarities include the absence of two Oregon display postures (tossing and swinging) and collective displaying among Arashiyama monkeys. The hypothesis ofModahl andEaton (1977) that male displaying influences the females' choice of male mating partners is discussed. The evidence suggests the Oregon monkeys have incorporated male displaying into their socio-sexual behavior to a greater extent than Arashiyama monkeys. However, field observations indicate that males who migrate to the Arashiyama B site during the breeding season can influence female choice by “advertizing” their location with displays.     

Description of Sarcocystis falcatula Stiles, 1893, a Parasite of Birds and Opossums1

ABSTRACT. Sarcocystis falcatula Stiles, 1893 is re-described. Intermediate hosts of the parasite which was earlier described as Sarcocystis debonei Vogelsang, 1929 are species of passeriform, psittaciform, and columbiform birds. In these birds, muscle zoites are 6.88 × 2.19 (4.8-8.4 × 1.2-3.6) μm and are enclosed in a cyst wall with regular protrusions, 1-5 μm long. The convoluted primary wall has multiple thin areas in the osmiophilic layer. Microtubules originate in the ground substance and extend to the tips of the protrusions. The only known definitive host is the opossum, Didelphis virginiana; rats, cats, a dog, and a ferret could not be infected from muscle cysts. Sporocysts from opossums infected from five different infected avian sources measure 11.2 × 7.4 (9.6?12.0 × 6.0-8.4)μm.     

Common Guillemot Uria aalge parents adjust provisioning rates to compensate for low food quality

The quantity and quality of food available within the foraging area set important constraints for chick‐rearing birds, but responses to low quality are not well understood. This study explored the potential for parent birds to adjust quantity (feeding rate) and quality (energy content) in chick provisioning, by studying Common Guillemots Uria aalge on Stora Karlsö, Baltic Sea, predominantly utilizing Sprat Sprattus sprattus, during conditions of high food quantity but reduced food quality. Quality is central to reproductive success in this single‐prey loader. From the chick's perspective, provisioning rates should be increased to compensate for low food quality and to fulfil its growing needs with increasing age. However, the high energy cost of flying in Guillemots makes it important for parent birds to minimize commutes to feeding areas. Provisioning parameters were recorded during three dawn‐to‐dusk watches each breeding season from 2005 to 2013, when clupeids, presumably Sprat, constituted 98% of chick diet. Generalized additive mixed models showed that both feeding rate and size of clupeids (a proxy for energy content) varied between years and changed non‐linearly with chick age, but that there was no change within breeding seasons. Chick age and year explained 36% of the variation in feeding rate but only 2% of the variation in the size of clupeids in chick diets. We conclude that parent birds tried to adjust both feeding rate and prey size, but were less successful with the latter. A strong negative correlation was found between annual feeding rates and size of clupeids, evaluated as the differences relative to the baseline year, and adjusted for the effects of chick age. Although the differences between years were small, the relationship indicates a compensation mechanism that does not seem to impact adult survival, and by which increased feeding rates can partly counteract reduced chick energy intake when food quality is low.     

The Paleogene fossil record of birds in Europe

The Paleogene (Paleocene-Oligocene) fossil record of birds in Europe is reviewed and recent and fossil taxa are placed into a phylogenetic framework, based on published cladistic analyses. The pre-Oligocene European avifauna is characterized by the complete absence of passeriform birds, which today are the most diverse and abundant avian taxon. Representatives of small non-passeriform perching birds thus probably had similar ecological niches before the Oligocene to those filled by modern passerines. The occurrence of passerines towards the Lower Oligocene appears to have had a major impact on these birds, and the surviving crown-group members of many small arboreal Eocene taxa show highly specialized feeding strategies not found or rare in passeriform birds. It is detailed that no crown-group members of modern 'families' are known from pre-Oligocene deposits of Europe, or anywhere else. The phylogenetic position of Paleogene birds thus indicates that diversification of the crown-groups of modern avian 'families' did not take place before the Oligocene, irrespective of their relative position within Neornithes (crown-group birds). The Paleogene fossil record of birds does not even support crown-group diversification of Galliformes, one of the most basal taxa of neognathous birds, before the Oligocene, and recent molecular studies that dated diversification of galliform crown-group taxa into the Middle Cretaceous are shown to be based on an incorrect interpretation of the fossil taxa used for molecular clock calibrations. Several taxa that occur in the Paleogene of Europe have a very different distribution than their closest extant relatives. The modern survivors of these Paleogene lineages are not evenly distributed over the continents, and especially the great number of taxa that are today restricted to South and Central America is noteworthy. The occurrence of stem-lineage representatives of many taxa that today have a restricted Southern Hemisphere distribution conflicts with recent hypotheses on a Cretaceous vicariant origin of these taxa, which were deduced from the geographical distribution of the basal crown-group members.     

Environmental and genotype-by-environment influences on chick size in the Yellow-browed leaf warbler Phylloscopus inornatus

Summary I investigated genetic and environmental factors affecting fledgling chick size in the Yellow browed leaf warbler Phylloscopus inornatus. The proportion of variation among broods is >45% for both tarsus length and body weight; this can be attributed at least in part to effects of the shared nest environment. A high off-spring-parent regression for weight also appears to be partly due to an environmentally induced correlation and the regression is reduced when effects of laying date are controlled for. A cross-fostering experiment demonstrated a significant nest of origin x nest of rearing interaction. The presence of genotype-environment interaction affecting chick size may be quite general in birds. It is shown how this can account for observed patterns of the dependence of the magnitude of offspringparent regression on prevailing conditions, as has been found in other studies. In P. inornatus the failure to detect significant genetic variance in chick body weight and tarsus length may be due to high standard errors on the estimates, but it may also reflect true low levels of genetic variance in chick size if the genotype-interaction effect described occurs regularly in this species.     

Factors determining the laying date of the Waved Albatross Diomedea irrorata

The Waved Albatross laying period is between mid-April and the end of June. This paper investigates the factors determining when, during this period, a female lays. It is shown that birds breeding for the first time lay relatively late. For older birds, the laying date depends on date and outcome of the previous year's attempt: females that bred successfully in the previous year lay slightly later than in that year, while birds that failed lay earlier. A corresponding difference exists in the dates of arrival at the breeding grounds of successful and failed males. It is argued that one calendar year is not quite sufficient for pairs that have reared a chick successfully to regain breeding condition, while failed breeders can choose the laying date more freely.
Under catastrophic El Niño weather conditions in 1983, all albatrosses arrived late at the breeding grounds, but still the birds that had failed in 1982 were clearly earlier than those that had reared a chick.     

FURTHER NOTES ON PAIRING AND SUBMISSIVE BEHAVIOUR OF THE RED-LEGGED PARTRIDGE ALECTORIS RUFA

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.     

Two new species of the genus Picobia Haller (Acari: Syringophilidae) from Australian and Indonesian passeriform birds

Abstract

Two new species of the quill mite genus Picobia Haller are described and figured from Australian and Indonesian passeriform birds: Picobia pyrrholaemus sp. nov. from Pyrrholaemus sagit‐tatus (Acanthizidae) from Australia and Picobia indonesiana sp. nov. from three Indonesian sturnid birds (Sturnidae): Aplonis panayensis (Scopoli), Enodes erythrophris (Temminck) and Mino dumontii Lesson.     

Sabelliphilidae (Copepoda: Cyclopoida) associated with the tube anemone Pachycerianthus maua (Carlgren) and the horseshoe worm Phoronis australis Haswell off New Caledonia

Acuaria paraguayensis n. sp. is described on the basis of specimens from Sirystes sibilator (Vieillot) (Aves: Passeriformes, Tyrannidae) in Paraguay. In addition, A. mamillaris (Molin, 1860) from Cyanocorax cayanus (L.) (Corvidae) in Brazil is redescribed on the basis of its type-series from the collection of the Naturhistorisches Museum, Vienna. A review of the species of Acuaria Bremser, 1811 in the New World is presented. Currently, 16 species belong to this genus, which are mostly parasitic in passeriform birds (one record in piciform birds). An identification key to the species of Acuaria occurring in the New World is presented. Acuaria multispinosa (Vigueras, 1938) originally described from Botaurus lentiginosus (Rackett) (Ardeidae) in Cuba, also known from various herons (Ciconiiformes, Ardeidae) in southern states of the USA, does not correspond to the generic diagnosis of Acuaria and is considered a species incertae sedis. Acuaria gracilis var. sturni Boyd, 1951 is elevated to full species rank as Acuaria sturni Boyd, 1951.     

Probing,Assessment and Management during Interactions between Ground Squirrels (Rodentia: Sciuridae) and Rattlesnakes (Squamata: Viperidae). 2: Cues Afforded by Rattlesnake Rattling

The predator-prey relationship between California ground squirrels (Spermophilus beecheyi) and northern Pacific rattlesnakes (Crotalus riridis oreganus) is a useful system in which to explore risk assessment and management. Rattlesnakes are major predators of ground-squirrel pups, but pose only a sublethal threat to adult squirrels. Adults approach, harass, and even attack rattlesnakes when confronted with them. A rattlesnake's response to such harassment can include rattling and striking. Not all rattlesnakes pose the same risk to an adult squirrel. Larger, warmer rattlesnakes strike in ways that may be more effective at overwhelming the defensive leaps of squirrels, and larger snakes can inject more venom if they are successful in landing a bite. It would therefore benefit squirrels to assess and respond appropriately to rattlesnakes of different body size and temperature. We looked for cues in rattling upon which such assessments might be based. We recorded and digitally analyzed the rattling sounds of snakes of different sizes, each tested at four different body temperatures — 10, 18, 27, and 35°C. Results indicate that warmer snakes rattle with faster click rates, higher amplitudes, and shorter latencies. Similarly, larger snakes produce rattling sounds of higher amplitude and lower dominant frequencies. Thus, rattling provides reliable cues about rattlesnake dangerousness. Nevertheless, this highly ‘informative’ characteristic of rattling has its origins in physical and physiological constraints, not in specialization for communication. Ground squirrels appear to probe for the information extractable from rattling, for example by pushing loose substrate at the snake and thus inducing it to rattle. Future reports will discuss the degree to which ground squirrels actually exploit these cues.     

Aus der Geschichte der Orientierungsforschung

Zusammenfassung Die Arbeit schildert die Entwicklungen auf dem Gebiet der Orientierungsforschung und den Wandel der Ansichten im Laufe der Zeit. Am Anfang stand Mitte des letztenJh. v. Middendorffs Vermutung, Zugvögel würden sich nach einem Magnetkompaß orientieren.Viguier diskutierte die Möglichkeit, verfrachtete Vögel würden anhand des Magnetfelds heimfinden, währendExner undReynaud kinästhetische Orientierungsmechanismen vermuteten. Erste Versuche, diese Hypothesen experimnentell zu bestätigen, blieben erfolglos.Anfang dieses Jh. versuchte man durch Verfrachtungsversuche festzustellen, unter welchen Umständen und über welche Entfernungen sich Vögel orientieren können. Seevögel zeigten sehr gute Heimkehrleistungen auch aus unbekanntem Gelände; die Versuche mit Brieftauben führten dagegen zu dem Schluß, Vögel könnten sich nur anhand bekannter Landmarken orientieren. In den 30er Jahren machten die systematischen Verfrachtungsversuche vonRüppell undWojtusiak jedoch deutlich, daß auch Stare und Schwalben von unbekannten Orten über große Entfernungen mit beachtlicher Geschwindigkeit heimkehren konnten. Die gleichzeitig begonnenen Versuche der Vogelwarte Rossitten und Helgoland zur Analyse des Vogelzugs ergaben, daß das Zugverhalten von den Bedingungen, unter denen die Vögel lebten, und bei sozialen Arten auch von Artgenossen mitbestimmt wird. Wildvögel zeigten bemerkenswerte Orientierungsleistungen, doch deren Grundlage blieb weiterhin offen.In den 40er Jahren führten die Untersuchungen vonHeinroth &Heinroth an Brieftauben abermals zu der Vermutung, die Heimkehr nach Verfrachtung beruhe auf mehr oder weniger systematischem Suchen, bis die Vögel auf bekanntes Gelände treffen; dann würden sie sich nach vertrauten Landmarken orientieren. Diese Ansicht fand weite Verbreitung;Yeagleys Hypothese einer Orientierung nach Magnetfeldparametern und der Coriolis-Kraft konnte sich nicht durchsetzen.Methodische Neuerungen leiteten Anfang der 50er Jahre die systematische experimentelle Analyse der Vögel ein.Kramer beschrieb den Sonnenkompaß und stelle mit dem Karte-Kompaß-Prinzip eine erste umfassende Theorie der Orientierung vor, die davon ausgeht, daß bei jedem Orientierungsvorgang ein externes Referenzsystem — ein Kompaß — beteiligt ist. Die Untersuchungen der Folgezeit führten zu einem recht guten Verständnis der Zugorientierung. Das Heimfinden nach Verfrachtung ist dagegen immer noch ein offenes Problem; keine der derzeit diskutierten Hypothesen kann alle bekannten Phänomene erklären. Es mehren sich jedoch die Hinweise, daß das Navigationssystem sehr variabel und in hohem Maße redundant ist, so daß mit einer einfachen Antwort gar nicht zu rechnen ist.

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On the history of orientation research

Summary This paper describes the developments and changes of ideas in the field of bird orientation research, which began in the middle of last century when v.Middendorff first suggested magnetic compass orientation in migrating birds. Still in the 19th century, two different hypotheses were proposed to explain homing.Viguier suggested that the birds made use of the spatial distribution of magnetic parameters, whereasExner andReynaud assumed that the birds were able to trace the route of the outward journey kinaesthetically. Attempts to obtain experimental support for either theory were unsuccessful.The first three decades of this century were characterized by displacement experiments designed to learn under what conditions and over what distances birds were able to return. The results obtained with seabirds indicated much more sophisticated navigational abilities than the experiments with homing pigeons, which led authors to believe that birds oriented by following familiar landmarks and could only return from unknown sites if they by chance reached a familiar region. This view became widely accepted when it was presented in the review articles ofWarner andStresemann.In the 1930s, however, systematic displacement experiments with wild birds changed the general views on orientation completely.Rüppell andWojtusiak showed that Starlings and Swallows could return from unknown sites over large distances with considerable speed. At the same time, the Vogelwarten (bird banding stations) Rossitten and Helgoland initiated programs to obtain more information on the nature of migratory orientation. The results indicated that migratory behavior can be modified by the conditions under which the birds live and, in social species, by conspecifics.Drost's experiment with Sparrowhawks gave the first indications that young birds and adult birds use different orientation mechanisms. Remarkable navigational abilities were demonstrated in wild birds, yet the mechanisms they used, were still unknown.The ideas on orientation changed again in the 1940s, whenHeinroth &Heinroth reported the resuls of their study on the orientation of homing pigeons. They suggested that pigeons, when released in an unfamiliar area, searched until they meet familiar terrain and then oriented by landmarks known from previous flights.Grifffin, whose attempts to interfer with homing by depriving displaced birds of magnetic and kinaesthetic information had failed, held similar views. A new global hypothesis byYeagley, suggesting that homing pigeons made use of a grid map formed by isolines of Coriolis force and vertical intensity of the magnetic field, was not accepted.In 1950, methodological innovations byKramer andMatthews brought new impetus to orientation research: It became possible to measure the directional tendencies of caged migrants, which allowed a systematic analysis of migratory orientation in the laboratory. At the same time, the vanishing bearings of displaced birds were found to be closely related to the home direction, which opened up new possibilities in pigeon homing.Kramer, who had described the sun compass as the first known orientation mechanism in birds, also contributed substantially to the theoretical framework of orientation by his map and compass-concept which states that an external reference system — a compass — is always involved in determining the home direction.The following period of experimental analysis began with a controversis on the role of the sun. Experimental evidence did not support sun navigation, but rather indicated that the sun was used as a compass. The analysis of the birds' orientation system during the last 30 years led to a fairly good understanding of migratory orientation. The processes of homing, however, are still not well understood. Many of the old concepts and new ones like olfactory orientation have been discussed, without any one hypothesis being able to explain all known phenomena. Recent findings suggest that there may not be one simple answer to the question of how birds navigate, as the birds' navigational system turns out to be redundant and highly variable.

     

Kymatocalyx Herz. in Mittelamerika

Summary A second species of the hitherto monotypic genusKymatocalyx Herz. is described and figured in detail. The new combinationKymatocalyx dominicensis (Spruce) comb. nova is proposed.     

Corpuscular and trilaminar appearance of cultivated chick embryo fibroblast plasma membranes

Summary Electron microscope examination of chick embryo fibroblasts grown in tissue culture and fixed in a variety of osmium fixatives as well as in fixatives not containing osmium revealed a limiting cell membrane with a corpuscular substructure. A trilaminar appearance was more difficult to demonstrate in plasma membranes of cells fixed in osmium or glutaraldehyde solutions followed by osmication, while many extensive regions of membranes with this appearance were observed after fixation in buffered potassium permanganate.A study of the conditions favorable to the demonstration of a trilaminar appearance indicated that the level of focus of the electron microscope image and alteration of the intrinsic structure of the summits within the membrane played significant roles in producing this appearance.This work was aided by Research Grant GB 2129 from the National Science Foundation. Some of the equipment used was purchased with funds from the National Institutes of Health Grant 2 TI GM 326. I wish to thank Dr. Robert M. Dougherty from the Department of Microbiology who grew and supplied me with the chick embryo fibroblast cultures used in these studies, and Mrs. Ursula Feller and Miss Leslie Hammack for their technical assistance.     

Ultrastructure of the developing gizzard epithelium in the chick embryo

Summary The fine structure of the gizzard epithelium is described at different stages in the development of the chick embryo. The elaborate apical processes, a characteristic feature, take part in secretion at thirteen days, but do not seem to have this function at nine and ten days. The formation of glands begins at thirteen days but the adult fine structure of the gland cells is not attained until hatching. The distinct surface layer present between thirteen and seventeen days may have a protective function. Acknowledgement. The author is grateful for research facilities provided by Professor G. M. Wyburn, Anatomy Department, The University of Glasgow.     

Individual variation in parental workload and breeding productivity in female European starlings: is the effort worth it?

We analyzed individual variation in work load (nest visit rate) during chick‐rearing, and the consequences of this variation in terms of breeding productivity, in a highly synchronous breeder, the European starling (Sturnus vulgaris) focusing on female birds. There was marked (10‐ to 16‐fold) variation in total, female and male nest visit rates, among individuals, but individual variation in female nest visit rate was independent of environment (rainfall, temperature) and metrics of individual quality (laying date, clutch size, amount of male provisioning help), and was only weakly associated with chick demand (i.e., day 6 brood size). Female nest visit rate was independent of date and experimentally delayed birds provisioned at the same rate as peak‐nesting birds; supporting a lack of effect of date per se. Brood size at fledging was positively but weakly related to total nest visit rate (male + female), with >fivefold variation in nest visit rate for any given brood size, and in females brood size at fledging and chick mass at fledging were independent of female nest visit rate, that is, individual variation in workload was not associated with higher productivity. Nevertheless, nest visit rate in females was repeatable among consecutive days (6–8 posthatching), and between peak (first) and second broods, but not among years. Our data suggest that individual females behave as if committed to a certain level of parental care at the outset of their annual breeding attempt, but this varies among years, that is, behavior is not fixed throughout an individual's life but represents an annually variable decision. We suggest females are making predictable decisions about their workload during provisioning that maximizes their overall fitness based on an integration of information on their current environment (although these cues currently remain unidentified).     

OBSERVATIONS ON THE BREEDING BEHAVIOUR OF GREY AND RED-NECKED PHALAROPES

Observations were made on Grey and Red-Necked Phalaropes near Chesterfield Inlet, N.W.T., Canada, from the date of their local arrival, 13 June, until 21 July 1967. The similarity of the colour of the Grey Phalarope nuptial plumage to that of dead seaweed among which the birds often feed is suggested as possibly relevant to the evolution of this plumage. A mutual Head Up pre-copulatory display, first given by the female, is described in Grey Phalaropes. It is suggested to have the function of assuaging fear in the prospective partner and to be a prelude of only the first copulation between any two birds. Other displays are described and figured. Three full copulations, including their preliminaries, were observed in this species and two others in which the preliminary actions escaped observation. Three copulations took place on land and two on water. Of the three copulations observed with their preliminaries, two were initiated by some form of display by the female, and one, without any display, by the male. Eight attempted copulations were observed; all were initiated by males and all but one took place while the female was on land. One male which had just copulated was observed to attempt copulation with another female. In the course of three full or attempted copulations, another Grey Phalarope fluttered up against the mating pair. All Grey Phalarope copulations took place in a collective feeding area; little intra-species antagonism was seen and no evidence of territorial behaviour. All female Grey Phalaropes left the colony under observation on the night of 9–10 July; only two eggs had by then been laid in one nest and the female of one pair had not laid at all. Six copulations and six attempted copulations were observed in Red-necked Phalaropes; all took place on the water. Only in two of the copulations were the preliminaries observed; one was initiated by a display of the female, the other without any preliminary display by the male. Preliminary observations suggest specific differences in rate of spinning and in the preferred direction of spin. The functions and factors associated with spinning are discussed. Accelerated spinning with reduced frequency of pecks at the water by both members of a pair of Red-necked Phalaropes was observed once and may have been a form of display. Head scratching, observed once in a Red-necked Phalarope and several times in Wilson's, is by the direct method, supporting the view, based on the colour pattern of the downy young, that phalaropes are more akin to the sandpipers than to the avocets.