Flight Song Research Articles

Nesting Biology, Seasonality, and Mating System of Malaysian Fantail Warblers

The breeding biology of Fantail Warblers (Cisticola juncidis) in a rice field in northwestern peninsular Malaysia was studied. Data were collected on 38 nests found in rice plants on the 15-ha study area. Clutch size was three or four, incubation lasted 10-14 days, and fledging occurred 14-15 days after hatching. Two breeding seasons occurred annually, January-March and June-September, coinciding with the availability of suitable rice field nesting cover. The presence of several closely spaced, simultaneously active nests on plots occupied by single male birds indicated a polygynous mating system. This was based on the ability of some males to monopolize the limited available nesting habitat early in the rice-growing cycle. These findings differ from those of previous studies, presumably because of differences in the habitat types and mating systems examined. The Fantail Warbler (Cisticola juncidis) is a small sylviid widely distributed in tropical and temperate parts of Europe, Africa, Asia, and Australia. It chiefly inhabits wet grassy areas and rice fields and is rather secretive except during the breeding season when males perform conspicuous aerial displays (Lynes 1930, Givens and Hitchcock 1953). Recent studies in Japan (Motai 1973), France (Robert and Bellard 1975), and Australia (Ey 1977) indicate that the species may be regularly polygynous throughout a substantial part of its range. In this paper, I present results of a study of the nesting biology and mating system of the Fantail Warbler in a Malaysian rice field environment. This research was part of an investigation of the influence of rice cultivation on the breeding seasonality of certain common rice field birds (Avery 1980), and it is the first detailed account of Fantail Warbler breeding biology from the Malayan region since Gibson-Hill's (1950) study, which was conducted on Singapore during the mid-1940's. STUDY AREA AND METHODS The study area consisted of 15 ha of experimental rice fields at the Rice Research Center of the Malaysian Agricultural Research and Development Institute at Bumbong Lima, Northern Province Wellesley (5033'N, 100028'E). The fields were irrigated, and two crops of rice were harvested annually in March-April and September-October. The study period was June 1975-March 1977. Most nests were found by observing the movements of adult birds carrying nest material or food. Other nests were pointed out to me by field workers. I visit6d each nest site every second or third day and recorded the number of eggs or young and the presence or absence of adults. Several nests were observed using a spotting scope in order to monitor the foraging activity of female birds. Boundaries between breeding territories were estimated by observing encounters between males during aerial displays. I distinguished sexes of adult birds by plumage differences (Chasen 1939) and behavioral traits (during the breeding season, males make extended song flights whereas females make brief, low, usually silent flights). Recently fledged birds were easily distinguished from adults by the yellow wash on the pale feathers of the breast and abdomen. Throughout the study, I mist-netted and banded birds, but did ot uniquely mark them for sight identification. Thus, individual recognition in the field was not possible. Field counts of birds on the study area were made an average of three times weekly to obtain an indication of population levels.

Territorial Behavior of a Blackbird: Mechanisms of Site-Dependent Dominance

AbstractThe behavioral mechanisms that produce territoriality require that a resident's agonistic tendencies vary with the locations of encounters with opponents or with the distance between the resident and an opponent. Variation in agonistic tendencies with location could result from increased aggressiveness in familiar locations. Only a few field studies have previously documented variation in aggressive tendencies either with the location of an encounter or the distance of an opponent. In this study, we measured the spatial distributions of advertising activities in the territories of male yellow-hooded blackbirds Agelaius icterocephalus and related these distributions to aggressive tendencies of the residents. Advertising and agonistic activities resembled those of other marsh-nesting blackbirds in the genera Agelaius and Xanthocephalus. To portray the spatial distributions of activities, we determined convex hulls for the 95 % and 68% of instances or seconds of an activity closest to the vector mean of the distribution. A territorial male's time perched conspicuously, instances of conspicuous perching, songs and song flights were concentrated near the center of his territory. In spite of this uneven distribution of a male's time and advertising activities within his territory, a male's aggressive tendencies toward intruders did not vary clearly either with the intruder's location or distance from the resident, provided only that the intruder was within the resident's boundaries. Interactions with neighbors suggested that use of an area is a prerequisite for its defense. Changes in boundaries and establishment of new territories revealed that a male's use of an area increased before aggression toward neighboring residents began. Changes in a resident's territorial boundaries often resulted from changes in the spatial distribution of residents' activities as a result of localizing activities around nests of egg-laying females or changes in the locations of nests under construction. These observations suggest that predominance in use of an area leads to dominance in defense of that area.

Intraspecific Social Stimulation and Temporal Displacement of Songs of the Lesser Skylark, Alauda gulgula

AbstractTemporal patterning of flight song activity was examined in a population of Lesser Skylarks in Viet Nam. Onset and termination of songs were timed. Temporal dispersion of songs was analyzed from the distribution of intersong intervals, and the tendency of songs to be started prior to, shortly after, or long after cessation of a neighbor's song was examined. Skylarks tended to sing sequentially, clustering their songs in time after long periods of silence. However, they showed a strong tendency to avoid overlapping songs, perhaps because of the possibility of jamming by songs of neighbors. These two factors, intraspecific social stimulation and temporal avoidance, appear to be important determinants of singing behavior in this species.

Temporal and Sequential Organisation of Song in the Sedge Warbler (Acrocephalus Schoenobaenus)

Temporal analysis has revealed that Sedge Warbler songs are unusually long, some extending over one minute in duration and containing over 300 syllables. They have a characteristic temporal pattern; starting slowly and building up to become faster, more complex and louder in the middle, before fading away towards the end. Song flights were not longer, but more complex in structure, containing twice as many syllable types as normal songs. Some individual differences were found, Bird I sang faster than the other two, and Bird 3 had longer songs which contained fewer syllable types. Sequence analysis revealed that the start section of the song consisted of long, complex patterns of repetition and alternation, usually involving only two syllable types. The middle section was characterised by a sudden switch, which introduced between 5 and 10 new syllable types in quick succession. The end section consisted of a similar pattern to the start, but the two syllable types were selected from the middle section. These were then used to form the start of the next song. Sequence analysis showed that overall syllable transitions were indeterminate, and this was confirmed by following in detail the many and complex relationships of selected syllable types. Even when songs containing the same syllable types were found, their transitions and detailed structure varied enormously. Considering the variable organisation described, the probability of a song type ever being exactly repeated seems remote. Sedge Warbler song is unusual in two respects; in its extreme elaboration and in functioning almost solely in sexual attraction of the female. It is suggested that these two factors are related, and that sexual selection may have played an important part in the evolution of one of the longest, most elaborate and variable of all bird songs.

Interspecific Aggression of Ash-Throated Flycatchers on Cassin's Sparrows

During the course of field studies in 1970 on the Santa Rita Experimental Range, Pima County, Arizona, we observed eight instances of interspecific aggression by Ash-throated Flycatchers (Myiarchus cinerascens) on Cassin's Sparrows (Aimophila cassinii). The former is a medium-sized tyrannid which nests in abandoned woodpecker holes in much of the southwestern United States and into M6xico. It forages mainly by hawking for insects from the upper limbs of trees. The sparrow is a ground-foraging species, feeding on seeds in winter and ground-inhabiting insects during the summer. Nests are placed near the ground in low vegetation. Its song is delivered in an upward arching flight from upper limbs of trees. The pattern of singing flights closely resembles the hawking maneuvers of the flycatcher. It was during the flight song that the sparrows were attacked by the flycatcher. The latter flew straight at the sparrow and usually knocked it to the ground. Apparently, the flycatcher was responding to a behavioral image which approximates its own foraging maneuvers. Selection against such behavior is probably weak since Cassin's Sparrow is rather restricted in its distribution and then only occurs in grasslands. On the other hand, strong selection pressures may operate to maintain this type of behavior in the flycatcher since it overlaps several potential competitors (Myiarchus spp., Tyrannus spp.). One other observation adds strength to the above suggestion. A Cactus Wren (Campylorhynchus brunneicapillus), flying about 3 m above the ground, suddenly made an upward jog in its straight line flight. This deviation was similar in form to a flycatcher foraging maneuver. Immediately, an Ashthroated Flycatcher, which was perched about 4 m away, flew at the wren and knocked it to the ground. These data were obtained during research supported by the US/IBP Desert Biome program under grant no. GB 15886 from the National Science Foundation.

Annual Testicular Cycle and Bill Color Change in the Eastern American Goldfinch

THE avian testicular cycle of seasonally-breeding birds consists of three phases: a regeneration phase when the tissues of the regressed gonad are reorganized, an acceleration phase characterized by development and growth of the testis, and a culmination phase in which the birds are responsive to certain environmental end stimuli that result in their nest building and gamete deposition (Marshall, 1961). Among wild populations of north-temperate passerines such a cycle has been demonstrated by histological examination of the testis in only a few early nesting species (e.g. Blanchard, 1941; Bullough, 1942; Blanchard and Erickson, 1949; Threadgold, 1956a, 1956b; Marshall and Coombs, 1957). Comparative study of the cycles of more species, particularly late nesters, is desirable. An analysis of seasonal changes in external characters that reflect seasonal changes in the gonad may provide an indirect method of determining the testis cycle in other species quickly. Bill color and postnuptial molt are well-suited for such an analysis as, in certain species, they are readily measurable from museum skins. Both characters have been correlated with changes in the titer of one or more of the gonadal hormones (Witschi and Fugo, 1940; Kobayashi, 1954a, 1954b, 1954c, 1958; Witschi, 1961; Engels, 1962), and Marshall (1961) associates the onset of the postnuptial molt with early regeneration phase and the termination of postnuptial molt with the onset of acceleration phase. The Eastern American Goldfinch, Spinus t. tristis, exhibits both a seasonal change in bill color and a late breeding season, and is principally single-brooded. Throughout the northern part of its range this goldfinch generally does not nest until July and later (Walkinshaw, 1938; Stokes, 1950; Nickell, 1951; Berger, 1968), and breeding behavior occurs seasonally later in this species than in other passerines nesting in northeastern North America. Field experiments conducted in Ithaca, New York revealed that not until late June or early July do female goldfinches begin gathering cotton artificially supplied them in their nesting habitat since early June, and they do not begin collecting thistle papus, a major natural nesting material, until July or, more rarely, in the last week of June (Mundinger, 1968). This correlates temporally with the onset of nest construction. In a study field in Ithaca only about 6 percent (2 of 35 nests) of all nests were initiated as early as the period mid-June to 1 July in 1963-65. Likewise the males do not engage in the defense of a geographically fixed area with flight song display and other territorial behaviors until nest construction begins or, in some cases, only a few days

Song Variation in a Population of Indigo Buntings

IN a previous paper (Thompson, 1968) I described the general characteristics of the songs of several species of the genus Passerina. For a fuller understanding of a behavioral characteristic, just as in the case of a morphological feature, it is important to study the kind and amount of variation within a single population and, especially for behavior, within a single individual. This paper describes the song characteristics of the members of a single population of Indigo Buntings, Passerina cyanea. A paper now in preparation will describe song variation in individual Indigo Buntings. Male Indigo Buntings sing three rather distinct types of song: advertising song (in the sense of Borror, 1961), a squeaky song in intensive territorial defense, and flight song. This paper deals only with advertising song. A typical Indigo Bunting advertising song is composed of a series of sounds, or song figures. The song in Figure 5A, for example, includes eight song figures of five different types. I define the term song figure (Thompson, 1968) as a sound or sounds that produce a single, complete, and distinct impression to the human ear and form a distinct unit of a song. A song figure may be composed of one or more continuous sounds or syllables. Each male Indigo Bunting usually sings a regular sequence of several different figures. Figures may occur singly in the song, or they may be repeated. In a typical advertising song repeated figures occur together. The fixed sequence of figures sung by each male is called a song pattern.

Singing Behaviour of Blue-Winged and Golden-Winged Warblers and Their Hybrids

1. Songs of 12 Blue-winged Warblers (Vermivora pinus), 7 Golden-winged Warblers (V. chrysoptera) and 5 obvious hybrids were studied in the field near Ithaca, New York, U.S.A. 2. The primary of the two species is distinctive. Hybrids sing one or the other of the parents' songs. Two birds had reversed songs, one a Blue-winged Warbler with Golden-wing song, the other a Golden-winged Warbler with Blue-winged song. The secondary song, sung early in the season only by disturbed birds or later in the season by undisturbed birds as well, is similar in the two species and hybrids. 3. Golden-winged Warblers and hybrids with Golden-wing vary the number of notes in their songs according to the context. Fewer notes are given after mating (especially near the female), and following encounters with other males. In most instances, the more intense the preceding encounter, the shorter the song. Blue-winged Warblers differ in that they do not change the directly at mating. A hybrid with a Blue-winged and a Golden-wing with Blue-wing resembled Golden-wings more in that they shortened immediately after mating. The only bird that lengthened his after mating was a Blue-wing with Golden-wing song. Both species and hybrids gave secondary songs following encounters with males. Secondary songs were usually given following more intense encounters than shorter versions of the primary song. Secondary songs under undisturbed conditions later in the season were more common in the Blue-wing. Flight songs which consist of secondary songs were observed only in Blue-wings and certain hybrids. Variants of this secondary occurred only in the Blue-wing. 4. The two species differed in the amount of after mating. Blue-wings had an abrupt decrease at the time of mating, Golden-wings a more gradual one. However, Golden-wings ceased singing earlier than Blue-wings and were usually silent during the parental phase. Hybrids resembled more the parent species whose they sang. 5. The sequential patterning of songs within bouts was studied in birds with Golden-wing songs. Songs beginning bouts had fewer notes than those ending bouts. Under undisturbed conditions, songs with the same number of notes tended to follow each other and there were only two types of songs per bout. However, when disturbed, there was more often skipping and more than two songs per bout. 7. A hybrid (character) index was constructed of plumage patterns of the two species and hybrids. Song form and singing behavior were also scored. Form of was not directly associated with plumage but singing behavior was. Therefore, these motivational factors are probably directly genetically controlled. 8. Evidence is presented that singing is a relatively independent tendency. Birds with Golden-wing songs give the primary when the singing tendency is strong. When the general singing tendency is weaker, either absolutely or relatively because of the influence of other tendencies, particularly escape, the is shortened. Secondary seems to occur when the escape tendency is even stronger and/or the singing tendency weaker. 9. The functions of the primary and secondary songs are different, secondary songs playing no role in mate selection. The Golden-wing has developed more complexity in the primary song, the Blue-wing in the secondary. 10. Those vocalizations termed song probably have diverse functions as well as motivations in different passerines as a consequence of different evolutionary histories.

Reliability of Censuses of Singing Male Woodcocks

Factors affecting the courtship performance of woodcocks (Philohela minor) and the accuracy of the annual Singing Ground Survey of the U. S. Fish and Wildlife Service were studied in 1963 and 1964. Woodcock courtship calls were counted at 2-min intervals, alternating each day between several areas of differing woodcock density. At the same time, cooperators made the standard Singing Ground Survey through the study area each evening. Climatic conditions were measured for each woodcock performance. The most stable courtship activity occurred from about April 15 to May 15 and appeared to be affected only by extremes in climatic conditions. The performance seemed to be initiated by light intensities averaging 2.1 footcandles, so that starting times were earlier in relation to official sunset when the cloud cover was heavier. Male activity increased briefly with the coincident appearance of many broods. As the density of performing males increased, the level of peenting activity per bird significantly decreased; courtship flight activity was less affected. As density increased, the probability of hearing individual males was reduced. The predawn performance was deemed unsuitable for surveys. Poor hearing ability of survey cooperators lowered the survey results significantly. The inclusion of flight songs was not detrimental to the daily tally, nor was the survey significantly affected by stage of the moon. Recommendations for singing ground survey changes are presented. Censuses of the American woodcock take advantage of the bird's spring courtship performances. These occur daily just before dawn and just after sunset on relatively open areas called singing grounds. The woodcock makes three principal sounds during its performance: a buzzing peent call, given on the ground, and during aerial displays a vocal chirping called the flight song, which is accompanied by a mechanical twittering made by the wings (reviewed by Mendall and Aldous 1943:57-61). Apparently, only males peent since, of 50 birds shot while peenting (Dr. F. W. Martin, personal communication, July, 1963), all were males. The Singing Ground Surveys of the U. S. Fish and Wildlife Service are made annually in selected woodcock areas throughout the eastern United States and southeastern Canada for a population index to help regulate woodcock hunting. A known singing ground is selected as the starting point and the census begins when the first male is heard. The observer travels by car over a planned route for 35 min at dusk, stopping at no less than 0.4-mile intervals, since it is believed that woodcocks may be heard for 0.2 mile. Stops may be made at greater intervals to avoid unsuitable situations such as busy road intersections. At each stop, the number of woodcocks heard performing during a 2-min counting period is recorded. Mendall and Aldous (1943) studied the ecology of the woodcock and initiated the survey method. Sheldon (1953) analyzed the Singing Ground Survey, studied the activities of single birds, and appraised trapping data in efforts to improve the survey. Goudy (1960) studied the effects of various factors on the survey results and attempted further refinement of the method. This study was conducted to determine what factors may influence the male mating performance and thus affect the population index as determined by the survey. Specifically, the purpose was to determine: (1) the most desirable daily and seasonal time for useful surveys; (2) the most desirable climatic conditions for useful surveys; (3) the effects of climatic and physical factors and population density on the courtship performance; (4) the effect of observer's hearing ability on survey accuracy; 1 This paper is based on a thesis submitted in partial fulfillment of the requirements for the M.S. degree in Fisheries and Wildlife, Michigan State University.

The Flight Song Display of Two Taxa of Vermilion Flycatcher, Genus Pyrocephalus

The Flight Song Display of Two Taxa of Vermilion Flycatcher, Genus Pyrocephalus

THE SONGS OF SOME FAMILIES OF THE PASSERIFORMES. H. THE SONGS OF THE BUNTINGS (EMBERIZIDAE)

Summary1. The songs of the Emberizidae are discussed. Recordings of at least one species of 18 of the 21 genera are analysed by means of the sonograph.2. The songs of this family are characteristically short, repetitive and simple, primarily for territorial proclamation and therefore with good specific differences.3. The similarities between the songs of the genera may be accounted for by convergence as many have similar reproductive and nesting habits.4. Many songs are stereotyped, but some show a great deal of variation, which in some cases may provide a means for individual recognition.5. Wheezing and buzzing, duration of song, and the tendency to deliver songs in bursts of one type are considered to be possible generic characters.6. A tendency for a lark‐like quality to be developed is found in those species with a song flight.

The Flight Song of the Prairie Horned Lark

The Flight Song of the Prairie Horned Lark

Status of Cassin's Sparrow in Arizona

As long ago as May, 1940, the writer became aware that current ideas concerning the status of the Cassin's Sparrow (Aimophila cassini) in the western part of its range were in need of revision. For three years, however, publication of these findings was withheld while further data were in prospect. Since it now appears unlikely that additional light will be thrown on the problem in the near future, I wish to call attention at this time to a situation which appears to be unique among North American birds. This sparrow first attracted the author's attention on July 19, 1939. On that date, with his friends Gale Monson and F. W. Loetscher, Jr., he visited a locality near Tucson, Arizona, where he had previously discovered surviving colonies of Rufous-winged Sparrows (Aimophila carpalis). He hoped to find a nest of the latter species while introducing it to his friends, who had never seen a Rufous-winged Sparrow before July, 1939. While driving along the road and visiting the Rufous-winged Sparrow colonies, the party saw about twenty-five Cassin's Sparrows, most of them males singing the hauntingly sweet song of this otherwise obscure sparrow. Under other circumstances, no particular attention might have been paid to them; ever since the days of Henshaw, in the early 1870's, it has been well known that the Cassin's Sparrow is often abundant in the grasslands of southeastern Arizona in late summer. Indeed, Loetscher and I had seen and taken these sparrows the day before at Sahuarita (south of Tucson) and on the Santa Rita Range Reserve without suspecting that anything was amiss. But on July 19 it was clear to me that there was something peculiar about these birds. Here they were in numbers, singing freely, and the males evidently in breeding condition, with their testes greatly enlarged; yet hardly a month before, and with no period intervening when our sparrows were supposed to be migrating, on June 16, 1939, I had visited these self-same spots without hearing or seeing a single Cassin's Sparrow! My next opportunity to visit these localities came in late August, a month later. The Cassin's Sparrows were still common on August 21 and 22; there were still quite a number of them, giving their flight song, on August 24 and 28; there were a few on September 1 and 6, but in September I heard little singing. By mid-September, what little singing there was was reduced to mere fragments of the full song. My last visit at this period was on September 12, when Lee W. Arnold and I saw only two Cassin's Sparrows.

Flight Song of the Blue-Winged Warbler

Flight Song of the Blue-Winged Warbler

Flight Songs and Mating Songs

Flight Songs and Mating Songs

Flight Songs and Mating Songs

Flight Songs and Mating Songs