Hand-reared Birds Research Articles

Fibre types in breast and leg muscles of hand-reared and wild grey partridge (Perdix perdix)

Fibre types and sizes and their relative numbers and cross-sectional areas in M. pectoralis, M. supracoracoideus, and M. iliotibialis of hand-reared and wild grey partridge (Perdix perdix) were determined in order to see if there are differences that could account for the poor survival of hand-reared birds released into the wild. Histochemical staining for myosin ATPase and succinate dehydrogenase (SDH) showed that most breast-muscle fibres (80-90%) are of the fast-twitch glycolytic (FG) type and a smaller portion of the fast-twitch oxidative glycolytic (FOG) type. In M. iliotibialis, about 60% of the fibres were FG fibres and the rest were of the FOG type. Judging from the low intensity of SDH staining, FOG fibres in the grey partridge appear weakly oxidative only. The relative number of FG fibres and their relative cross-sectional area in M. pectoralis were larger in the hand-reared than in the wild birds. The cross-sectional areas of both fibre types in M. iliotibialis were significantly larger in the hand-reared birds. Taken as a whole, these findings alone do not account for the poor survival of hand-reared partridge in the wild.

Effects of Hand-Rearing and Radiotransmitters on Flight of Gray Partridge

Takeoff ability has an important role in escape from a predator in the gray partridge (Perdix perdix). Rearing in captivity and radiotagging may impair the takeoff ability of birds. To test this, the takeoff angle, flight speed, and climbing rate of wild and hand-reared gray partridges were measured indoors with an optoelectronic motion analysis system. In addition, we tested the effect of an attached radiotransmitter on the takeoff ability of wild partridges. Wild birds had a steeper takeoff angle (P = 0.001) and greater climbing rate (P < 0.001) than hand-reared birds. The transmitter decreased takeoff angle (P = 0.006) and climbing rate (P = 0.002) of wild partridges. The negative effect of hand-rearing and radiotagging on takeoff ability may increase gray partridges' vulnerability to predation.

Social Dominance in Young White-Throated Sparrows: Effects of Early Social Experience and the Unstable Period

ABSTRACr.-I examined the influence of early social experience on winter dominating ability in White-throated Sparrows (Zonotrichia albicollis). Eleven sparrows from four broods were hand raised to independence, housed in flocks with their brood mates for 8 to 9 weeks, placed in isolation or in a flock of six for an additional 17 weeks (the experimental phase), and then tested for in one of three juvenile flocks consisting of unfamiliar hand-reared birds and wild-caught birds. The mass of a nestling relative to its brood mates was not correlated with its final dominance, and no dominance interactions were observed between nestlings. Similarly, although an unstable period occurred in the brood-mate flocks during which dominance relationships fluctuated greatly from day to day, neither dominance status nor total number of dominance interactions in the brood-mate flocks was correlated with final dominance. In contrast, social conditions imposed during the experimental phase appeared to influence final dominance strongly. Three of five isolates achieved the top rank in final flocks, sparrows from the experimental flock were all of low rank, and wild-caught sparrows attained intermediate rank. These results suggest that the social conditions experienced by juvenile White-throated Sparrows before they leave the breeding ground and during fall migration might have a lasting effect on their dominance status and, thus, their survival in winter. Received 14 October 1994, accepted 5 April 1995.

Fear and Food Recognition in Naive Common Ravens

Fear and Food Recognition in Naive Common Ravens

Startle and Habituation Responses of Blue Jays (Cyanocitta Cristata) in a Laboratory Simulation of Anti-Predator Defenses of Catocala Moths (Lepidoptera: Noctuidae)

AbstractBlue jays were used in laboratory experiments to determine what visual characteristics of Catocala hindwings are important in eliciting and maintaining startle reactions in avian predators. Hand-reared blue jays, inexperienced with warningly coloured, inedible prey, took significantly longer to touch novel colours that possessed bold, black bands than to touch novel, unbanded colours when these discs covered a food reward. Thus, being conspicuous (as opposed to simply being novel) appears to enhance startle reactions. Bold patterns are commonly found on aposematic prey and Catocala hindwings. These same hand-reared birds also tended to take longer to touch novel coloured discs of yellow and red hues as opposed to discs of blue, green, or purple hues. The colours that produced the greatest hesitation are similar to the colours found on Catocala hindwings. Red-yellow colours are also characteristic of aposematic prey. Wild-caught birds took longer to habituate to startling stimuli when presented with several different startling disc types during the habituation process. Thus, predator pressure may explain why several different Catocala species with different hindwing colours occur sympatrically.

Factors Affecting Winter Pheasant Density in British Woodlands

Winter pheasant densities were obtained by drive counts in 189 sample areas of woodland from 17 sites. Measurements of woodland size, shape and structure, the extent of rearing, supplementary feeding and the habitat of the surrounding lands were recorded for each drive. Forward stepwise multiple regression and principal component analysis of 153 woods from 13 sites were used to identify factors related to winter pheasant density. On a within-site basis small woodlands with a high proportion of shrubby cover (100-200 cm in height), and the provision of supplementary feed were all associated with high pheasant densities. Pheasant density declined through the winter. On a between-site basis, high pheasant densities were associated with the release of hand-reared birds

Estimating the nesting success and productivity of British pheasantsPhasianus colchicusfrom nest-record schemes

Records of Pheasant nests from the British Trust for Ornithology's (BTO) Nest Record Scheme and The Game Conservancy's Pheasant Nest Recording Scheme (PNRS) were analysed. Mean clutch size was 11.4 and hatchability of eggs averaged 86%. Daily rates of clutch loss were 2-3 times higher on the day following the nest being discovered, associated with an increased rate of abandonment. After this, daily rates of loss during laying were 0.070 and 0.114 and losses during incubation were 0.015 and 0.028 from the PNRS and BTO samples, respectively. Calculations suggest that 53% and 25% of females successfully produced a brood from the PNRS and BTO samples, respectively. The figure from the BTO sample is probably too low to sustain a population. It is suggested that the low rate of brood production is caused by the widescale release of handreared birds which are known to breed poorly.

Comparison of the Breeding of Hand‐ and Wild‐Reared Snowy Plovers

The release of captive-reared birds has led to the reestablishment or augmentation of wild populations of several avian species threatened by extinction (Kear 1972; Barclay & Cade 1983; Shepard 1986). Shorebirds should be very suitable candidates for captive-rearing projects because of their strongly developed innate behavior and offspring precocity. More specifically, hand-reared birds, raised without parents or foster parents, could prove valuable for augmenting coastal snowy plover (Charadrius alexandrinus) populations, which have been eliminated from sizable sections of their former breeding range (Page & Stenzel 1981). Consequently, we compared survival and initial breeding success of handand wild-reared released snowy plovers to evaluate the potential of a captive-rearing program for plovers.

Panting and acid-base regulation in heat stressed birds

1. 1. Studies in respiratory physiology and acid-base balance of panting birds exposed to high T a s show that flying as well as nonflying birds can use the respiratory system simultaneously for gas exchange and evaporative cooling. 2. 2. The present study proves that well acclimated hand-reared birds can effectively regulate a normal CO 2 level and acid-base status in arterial blood, when exposed to extremely high temperatures (50–60°C). 3. 3. In many birds practising simple or “flush out” anting, the dead space can be reduced to a volume which is estimated to be approx 15% the volume of the respiratory tract. 4. 4. These two modes of ventilation, shallow and high-rate, restricted to the nonrespiratory surfaces, may ensure the avoidance of CO 2-washout and limit lung ventilation to the volumes needed for oxygen consumption. 5. 5. This view supports earlier theories, suggesting the existence of physiological shunt mechanisms which operate during thermal panting in birds.

Dispersal and competitive ability in the magpie: an experimental study

During the winter, non-territorial magpies, Pica pica, lived in a flock where individuals competed for food items. In this study males dominated females. Taking each sex separately, the body size of individuals was not related to their dominance status. Older birds dominated later-hatched individuals. There was also a positive correlation between post-fledging dispersal and status. Individuals that had left their natal territory to join the flock had a lower status than those remaining at home. The effect of dispersal on status was also related to the time at which dispersing birds arrived in the flock. To distinguish between these two effects of dispersal, three groups of hand-reared birds were introduced into a flock during the winter. This experiment demonstrated that (1) dispersal was more important than other differences in determining the outcome of interactions, and (2) this effect of prior residence depended on the duration of an individual's residence relative to that of its competitors.

Experiments on the origin of dialects in the short-toed tree creeper (Certhia brachydactyla)

Wild short-toed tree creepers in southern Germany were exposed to tape recordings of seven song types from other dialects or song institutions and sixteen song types from thirteen handreared Middle European birds. One song type from southern Germany was used as a control. The males reacted strongly to two slightly different Spaish dialects and not at all or only feebly to one song institution from Cyprus and four from Morocco. The song types of the hand-reared birds had less effect than controls. The songs of two birds from southern Germany hand-raised together were quite similar to those from Cyprus. We conclude that Cyprus and North Africa on the outskirts of the species distribution were colonized by short-toed tree creepers who had had no opportunity to learn their songs from adult conspecifics.

Spacing and Three-bird Flights of mallards breeding in pothole habitat

Wild mallards (Anas platyrhynchos) were observed in pothole habitat near Minnedosa, Manitoba. The breeding mallards behaved territorially: both members of a pair were attached to a fixed area, and males were aggressive toward intruding females and pairs. Territorial behaviour was most pronounced during a brief period (13–22 days) from just prior to laying until early incubation. The most frequently observed aggressive behaviour pattern was the Three-bird Flight which effectively expelled intruders from the territory. The behaviour of birds in one area where density was artificially increased through the release of hand-reared birds of wild stock was compared with that of mallards under natural conditions. Under higher population density, pairs occupied smaller territories, the frequency of Three-bird Flights was reduced, and the average length and number of participants in each pursuit was reduced. Territorial behaviour in mallards appears to have evolved because of advantages to the male in preventing cuckoldry by defending his mate from males intent on forced copulation, alerting her to the presence of predators, and in allowing her to feed with a minimum of interruption during this period when she has special nutrient requirements. Three-bird Flights do not appear to be strictly territorial. Males appear to employ a mixed reproductive strategy whereby they defend their mates and also seek to inseminate females other than their mates.

Vocal Dueling among Male Marsh Wrens: Evidence for Ritualized Expressions of Dominance/Subordinance

-Male Marsh Wrens' (Cistothorus palustris) sing with immediate variety (i.e. AB CDE . . .); they progress rapidly through their song repertoires and tend to countersing with same song types. Intensive study of two hand-reared males in laboratory now confirms that both song types and song sequences are learned. Furthermore, leader/follower roles during countersinging duels are not determined at random. In this study, Bird 1 dominated Bird 2 in physical encounters; Bird 2 often followed (i.e. matched) song type just sung by Bird 1, but Bird 1 matched songs of Bird 2 only when songs of latter were electronically amplified. The leader/follower roles in countersinging may be ritualized expressions of dominance and subordinance, respectively, and could reveal to both males and females relative vigor of combatants. Received 20 November 1978, accepted 26 March 1979. IMITATION plays an important role in ontogeny of song in many songbird species (e.g. Nottebohm 1972, Kroodsma 1977), and if juveniles either remain at or return to locality where songs were learned, interacting breeding males will possess similar songs. If a male has only one song type in his repertoire, temporal adjustments in song delivery may be used to achieve interference or avoidance (Wasserman 1977), but when males imitate several songs and develop sizeable repertoires of different song types, potential for complexity of interactions during countersinging is escalated. Studies of Chaffinches (Fringilla coelebs), Great Tits (Parus major), Black-crested Titmice (Parus bicolor), Cardinals (Cardinalis cardinalis), Rufous-sided Towhees (Pipilo erythrophthalmus), etc., have revealed that neighboring males often respond to one another or to a tape recording (of a song from local dialect) with matching song types (Hinde 1958, Gompertz 1961, Lemon 1968a, b, Kroodsma 1971, respectively; see Falls and Krebs 1975 for an apparent exception to this pattern). Males of these species typically sing a song type several times before switching to another (i.e. AAAA . . . BBBB . . .), but potential for vocal interactions is further heightened when successive songs are usually different (i.e. ABCDE . . .), as in Marsh Wren (Verner 1975). With such a rapid interchange of song types, roles of leader and follower in countersinging become immediately evident. Verner (1975: 295) speculated that this song-matching during countersinging reflected the dominance/subordinance relationships between neighbors, but because of complexity of both song repertoire and interactions in field, he could not adequately document relationship among males. Having studied this phenomenon in laboratory with hand-reared birds, I can now (1) confirm that both song types and favored sequences in this complex behavior are learned, (2) reveal that roles of leader and follower in countersinging duels are not determined at random, and (3) support hypothesis that such vocal dueling, together with loudness of delivery, is a reflection of size, age, and/or dominance/subordinance relationships and might be I See Kroodsma and Verner (1978) for encouraged change of common name from Long-billed Marsh Wren to Marsh Wren. 506 The Auk 96: 506-515. July 1979 This content downloaded from 157.55.39.147 on Wed, 18 May 2016 06:05:48 UTC All use subject to http://about.jstor.org/terms July 1979] Vocal Dueling among Marsh Wrens 507

Energetic Requirements for Growth of the Jackass Penguin

AbstractEnergetic requirements for growth of the jackass penguin (Sphenisaa demersus) were studied by hand-rearing captive chicks, and by observing growth rates, feeding rates and meal sizes in the field. Daily gain in mass was highest in the period of linear growth (23-55 days). Daily relative growth decreased with age. Food intake and guano production increased from 20-40 days and thereafter remained constant. Relative food intake decreased with age. Digestive efficiency increased with age, and energetic content of guano decreased with age. Chicks in the field grew at a slower rate than the hand-reared birds and were estimated to have consumed approximately half as much food by time of fledging. Feeding of chicks in the field occurred mainly in the afternoon and daily food intake increased with age. It is possible that the slower growth rates in the field may be due to the necessity for parents to guard chicks from predators, after the onset of the chicks' full thermoregulatory abilities.

Comparative Feeding Ecology of Two Geographical Forms of the Varied Tit, Parus varius varius in Southern Izu Peninsula and P. v. owstoni in Miyake I. of the Izu Is

Comparative feeding ecology of two geographical forms of the Varied Tit, P. v. varius in southern Izu Peninsula and P. v. owstoni in Miyake I. of the Izu Is. was studied during April 1972 to March 1975. The main method of the observation was as follows. Feeding sites, foods, and feeding methods were divided into several types respectively, and the number of observations in each type was recorded while walking a regular course in a constant speed. The nature of the feeding activity recorded was that first seen. The observation was carried out in the same frequency every month. Then the observation rate (%) in each type was calculated and was tabulated later. The followings are the results.1. Feeding sites. Both of P. v. varius in S. Izu and P. v. owstoni in Miyake tend to feed most often in the twigs and leaves at all seasons except winter. However, varius in S. Izu fed often in the uppermiddle layers of the forest, while owstoni in Miyake fed often in the middle-lower layers. Furthermore, owstoni in Miyake fed much more often on the ground, especially in winter, than did varius in S. Izu (Table 1, Table 2). These differences were thought to be partly due to the difference of the environments investigated (this was also based on the difference of the habitat preference), and partly to the difference of the food habits.2. Feeding methods. Both of them used most often the hanging method and the flycatchings in getting nuts and berries, and used most often the hanging method in catching insects (Table 3). While eating, in both of them, nuts were held by both feet, and insects were held by one foot. Furthermore, the foot predominantly used in holding insects was almost determined in each bird in both subspecies. Therefore, in the feeding method, they showed the resembrances rather than the differences, and so this habit may be common to all populations of the species.3. Foods. Foods of both forms were composed mainly of animals, such as insect larvae, in the breeding season. In winter, however, they fed more often on nuts and berries (Table 4 and Table 6). This disposition was remarkable in P. v. owstoni in Miyake I., and the form fed especially on the nuts of Castanopsis cuspidata. This higher dependence on that nuts in owstoni in Miyake I. was thought to be based on the ecological poverty of the island.4. Storage of foods. This habit was observed in both form, but the frequency of observations was higher in P. v. owstoni in Miyake I., partly because of the easiness of observations. In owstoni in Miyake I., the store of foods could be observed during August to February, and the main foods stored were the nuts of Castanopsis cuspidata, and also Styrax japonica (Table 8). It was thought that almost all of the nuts of Castanopsis cuspidata ate in winter to spring were those stored in earlier periods. The storing behaviour was observed under capitivity in both forms, and this behaviour may be innate, because it could be seen in the hand-reared birds which were brought within a week after hatching and were kept in isolation from the adult birds.

A Study of Prey-Attack Behaviour in Young Loggerhead Shrikes, Lanius Ludovicianus L

i) Prey-attack behaviour by young Loggerhead Shrikes was studied in both wild and hand-reared birds. 2) Field work was done in central Washington state. 3) There did not appear to be any attempt by the parents to demonstrate prey-attack to either nestlings of fledglings. The young normally did not observe adults either killing or manipulating food until they were past the age at which they could kill for themselves. 4) The development of prey-attack behaviour in hand-reared shrikes takes approximately 37 days; prior experience with small food can hasten the appearance of this behaviour by up to 10 days. 5) Experience of any kind is unnecessary; the entire behaviour, which involves directing pecks to the back of the neck of large prey, is displayed by any shrike 40 days old or older. 6) A series of 12 generalized models was used to attempt to find out what cues are used by Loggerhead Shrikes to direct their attack at a novel potential prey item. 7) The shrikes responded significantly to each cue tested. 8) Motion was by far the most powerfully directing of the cues given. 9) There is evidence to suggest that the response to the other cues may have been due entirely or in part to curiosity. 10) Experience with live mice does not affect subsequent model attack behaviour. 11) Experiments with stuffed mice show that there are other cues not tested in the model experiments to which the shrikes are capable of responding, and which enable the birds to attack the neck of a still 12) These cues are only effective when the stuffed mouse is in an upright (normal) position; the same mouse on its side evokes a very different response. 13) These factors are apparently not present in stuffed birds. 14) Therefore, in addition to a generalized response to vertebrates, in which motion is very important, the shrikes may possess an innate recognition of ,, mouse. Since mice are best equipped to harm shrikes if the initial attack fails, such an innate recognition would seem to be highly adaptive.

Effects of early experience and testosterone on song as a reinforcer

Thirty-seven out of forty-nine 1st-year male chaffinches showed some reinforcing effect of song, with perching on a particular perch as the operant response. Of the birds that were injected with testosterone, those reared in the wild showed a significantly higher reinforcing effect than did those which were hand-reared, either in isolation from adult song or while tutored with adult song from a tape recorder. Furthermore, testosterone injections tended to increase the reinforcing effect for both autumn-caught birds and hand-reared birds. These two conditions which increased the reinforcing effect of song are also those which Thorpe (1958) found necessary for normal song development, and this suggests that reinforcement does play a part in normal song learning.

The Ontogeny of Impaling Behaviour in the Loggerhead Shrike, Lanius Ludovicianus L

Abstract1 . The ontogeny of impaling (including wedging) behaviour by Loggerhead Shrikes was studied both in wild and in captive birds. 2. The earliest elements of impaling: "dabbing" and "dragging" behaviour, are described. 3. Field work was done in central Washington state; most of the data were obtained from two broods totalling 13 birds. Laboratory work was done on more than 60 hand-reared birds. 4. There did not appear to be any attempt by the parents to demonstrate impaling to either nestlings or fledglings. The young normally did not observe adults impaling food until they were past the age at which they start impaling by themselves. 5. The ontogeny of impaling under natural conditions was found to be essentially Identical to that of hand-reared birds that had been raised in cages containing natural branches. 6. The earliest dragging behaviour by both captive and wild birds was done as soon as the food was obtained, whether or not the bird was within reach of a thorn or fork. 7. The motor patterns of impaling (dragging behaviour) appeared in every young shrike by the age of 26 days. However, a period of trial-and-error behaviour was apparently necessary before these motions were directed towards a suitable place (i.e., thorn or fork). 8. Observational learning is not involved; birds that had been reared in the absence of any impaling device until they were at least 75 days old failed to use thorn branches when provided, regardless of whether or not they had had the opportunity to observe older birds impaling and wedging in an adjacent cage. 9. It is, therefore, concluded that personal experience with impaling devices is necessary for the appearance of the orientation component of impaling in Loggerhead Shrikes. Furthermore, this experience must occur within a "critical period" whose boundaries are roughly 20 to 70 days after hatching. 10. Hence, in this species, the orientation component of impaling is apparently normally learned by a process similar to imprinting.

Premigratory Behavior and Orientation in Blue-Winged Teal (Anas discors)

NUMEROUS investigations have been made on avian behavior during migration. Almost all sight, sound, and radar observations of migrating birds show good correlations with weather conditions (Hochbaum, 1955; Lack, 1963). Orientation studies of caged birds during migration indicate that birds utilize celestial cues (Kramer, 1952; Sauer, 1961; Hamilton, 1962) as do directions taken by released birds (Matthews, 1961; Bellrose, 1963) and homing experiments (Matthews, 1955; Kramer, 1957). Recordings of caged birds show premigratory nightly unrest and indicate a bird's physiological readiness to migrate. Although these studies enhance our understanding of avian behavior during migration, information is scarce on the bird's activities on the breeding grounds prior to and during periods of migration. The objectives of this study were 1) to ascertain if any behavioral changes took place prior to as well as during migration, 2) to determine if these were associated with specific weather patterns, and 3) to see if all birds under observation reacted at the same time and in a similar manner to the same environmental conditions. The investigation included more than 340 hours of observations of birds in the field, of wild birds placed in orientation cages, and of a group of hand-reared birds in a large flight pen. The study was conducted with Blue-winged Teal (Anas discors) during the summer of 1963 and 1964 on the Delta Marsh, a large waterfowl breeding area at the southern tip of Lake Manitoba in Manitoba, Canada.

Survival in the Wild of Hand-Reared Passerine Birds

Survival in the Wild of Hand-Reared Passerine Birds