Incubation and Nest-Building Behaviour of Black-Headed Gulls III : the Pre-Laying Period

Behaviour ◽  
1963 ◽  
Vol 21 (1-2) ◽  
pp. 13-77 ◽  
Author(s):  
C.G. Beer
Keyword(s):  
Nest Building ◽  
Necessary Condition ◽  
Brood Patch ◽  
Temporal Proximity ◽  
Incubation Behaviour ◽  
Nesting Behaviour ◽  
Males And Females ◽  
Building Behaviour ◽  
Natural Situation ◽  
Close Temporal Proximity

Abstract(I) Elements of incubation behaviour and nest-building behaviour that are performed by Black-headed Gulls in the pre-laying period are described as they appear in the natural situation and when a model egg is placed in the nest. (2) Quantitative material is presented and shows the following:- (a) Time spent on the territory, time spent sitting in the nest, the frequency of settling, the proportion of complete settlings, the proportion of relatively long combinations of pre-settling movements, and the frequency of sideways-building all increase steadily as the date of laying draws closer. This is not true for time spent by partners together on the territory or the frequency of collecting trips. (b) Time spent on the territory, time spent sitting in the nest, the frequency of settling, and the frequency of sideways-building vary together to significant extents; this is at least partly a result of common correlation with the passing of time. Settling and sideways-building, however, remain highly significantly correlated after the effects of common correlation with all other variables are eliminated. (c) Performances of settling and sideways-building tend to occur in close temporal proximity to each other. (d) Comparison with the behaviour in the natural situation shows that presence of an egg in the pre-laying period depresses the amount of time spent on the territory somewhat but increases the amount of time spent sitting in the nest, the frequency of settling, and the frequency of sideways-building. Frequency of collecting trips and amounts of time partners were together on the territory were not affected by presence of the model egg. Presence of an egg in the nest is almost a necessary condition for performance of shifting and quivering in the pre-laying period. (e) Most collecting trips are performed when the partners are together on the territory. This is not true for settling or sideways-building. (f) Males perform more settlings, more sideways-building movements, more collecting trips, and spend more time sitting in the nest than females but the partners spend more or less equal amounts of time on the territory. (g) The evidence suggests that sideways-building has more causal affinity with settling and sitting in the nest than with collecting trips. (3) A sample of brood-patch and gonad measurements from birds found at different stages of the pre-laying period indicate that, in both males and females, defeathering of the brood patches begins some time before eggs are laid, and that changes in these structures may develop parallel with, and be implicated in, the changes in sitting and nesting behaviour in the pre-laying period.

Incubation and Nest-Building Behaviour of Black-Headed Gulls

Behaviour ◽  
1966 ◽  
Vol 26 (3-4) ◽  
pp. 189-214 ◽  
Author(s):  
C.G. Beer
Keyword(s):  
Incubation Period ◽  
Reproductive Season ◽  
Nest Building ◽  
External Control ◽  
Parental Behaviour ◽  
Incubation Behaviour ◽  
Building Behaviour ◽  
Natural Situation ◽  
Incubation Pattern

Abstract(1) Parental behaviour, and its development from incubation behaviour during the reproductive season, is described. (2) Day to day observations of the natural situation showed that elements of the incubation pattern persist throughout the post-hatching period but progressively decline in quantity, duration and completeness. (3) Substitution of eggs for chicks also showed that the readiness to show incubation responses in a standard incubation situation declines progressively during the post-hatching period. (4) A certain amount of experience with hatched chicks renders Black-headed Gulls incapable of immediately returning to sustained incubation behaviour if the conditions of the incubation period are restored. (5) Failure of the eggs to hatch results in extension of the incubation behaviour period beyond the normal time. (6) Premature introduction of hatched chicks in the nests of incubating gulls can cause the gulls to switch to parental behaviour and so end the incubation behaviour period before the normal time. (7) The timing of the change from incubation to parental behaviour is thus mainly a matter of external control. (8) Certain of the relationships found to hold between responses having an incubation function and responses having a nest-building function in the earlier phases also hold in the post-hatching period.

Impact of Embryonic Vocalizations On the Incubation Behaviour of Eared Grebes

Behaviour ◽  
1996 ◽  
Vol 133 (3-4) ◽  
pp. 145-160 ◽  
Author(s):  
Robert B. Brua
Keyword(s):  
Incubation Period ◽  
Exposure Time ◽  
Incubation Time ◽  
Nest Building ◽  
Behavioural Changes ◽  
Percent Time ◽  
Podiceps Nigricollis ◽  
Incubation Behaviour ◽  
Males And Females ◽  
Egg Turning

AbstractTwo experiments were performed during the summers of 1991 and 1992 to determine whether embryonic vocalizations cause changes in the behaviour of adult eared grebes (Podiceps nigricollis) during late incubation. In Experiment 1, a vocalizing egg was substituted in 14 nests, two days before the first egg in that nest was to begin vocalizing. Parents reduced the amount of rising and resettling and the time spent off the nest while incubating and increased the frequency of egg turning, nest building, and percent of time the 'off-duty' parent spent near the nest. Only nest builds per h in the pre-peep period differed between the sexes in Experiment 1. For Experiment 2, the incubation period was extended by two days. At that time a vocalizing egg was substituted in 15 nests. Males reduced the amount of rising and resettling, whereas there was no difference between periods for females. Males and females reduced the amount of time spent off the nest while incubating. Egg turns per h, nest builds per h, and the percent time the off-duty parent spent near the nest increased for both sexes. No differences between males and females were detected except for egg turns per h during the peeping egg stage of Experiment 2. Parents also brought food to the nest in response to embryonic vocalizations. The behavioural changes by eared grebes during late incubation appear to be due to embryonic vocalizations. Several changes in behaviour are consistent with the care-soliciting hypothesis, such as reduction in exposure time of the embryo and possibly shortening of the incubation time of the embryo by an increased egg turning rate. Presenting food at the nest and possible acceptance of the young are further adaptive features of embryonic vocalizations.

EFFECTS OF OVARIAN STEROIDS AND PROLACTIN ON THE SEQUENTIAL DEVELOPMENT OF NESTING BEHAVIOUR IN FEMALE BUDGERIGARS

1975 ◽  
Vol 67 (1) ◽  
pp. 29-39 ◽  
Author(s):  
R. E. HUTCHISON
Keyword(s):  
Initial Phase ◽  
Treated Group ◽  
Egg Laying ◽  
Patch Area ◽  
Ovarian Steroids ◽  
Brood Patch ◽  
Sequential Development ◽  
Incubation Behaviour ◽  
Nesting Behaviour ◽  
Precocious Development

SUMMARY As intact, breeding female budgerigars approach egg-laying, they spend an increasing amount of time in the nestbox and nest hollow. The brood patch area begins to defeather and becomes vascular and the oviduct increases in weight. Precursory albumen forms in the tubular glands of the oviduct. Oestradiol (OB) treatment in combination with prolactin (OB + PL) induced ovariectomized budgerigars to display nesting behaviour which did not differ from that shown by intact females in the 3 days immediately preceding egg-laying. In contrast, OB induced only the initial phase of the nesting sequence and the effects of OB in combination with progesterone (OB + PR) were intermediate between treatments with OB alone and OB + PL. Incubation of artificial eggs occurred only in the OB + PL group and the latency to display of the incubation posture was shorter in the OB + PL group than in the OB + PR group. No incubation posture was displayed by the OB-treated group. Oviduct development was not influenced by prolactin, but progesterone induced precocious development of tubular glands in the magnum region of the oviduct. Treatment with OB + PR induced uniform development of precursor albumen in the tubular glands. Development of the brood patch occurred with both OB + PL and OB + PR treatment. However, OB + PR resulted in defeathering which was advanced in relation to vascularity when compared with intact breeding females, whereas defeathering and vascularity of the OB + PL group did not differ from that of intact females at egg-laying. These results indicate that prolactin in combination with oestradiol was more effective than progesterone not only in inducing the later phases of nesting behaviour but also in initiating incubation behaviour and defeathering of the brood patch area.

The effect of straw on farrowing site choice and nest building behaviour in sows

1992 ◽  
Vol 54 (1) ◽  
pp. 129-133 ◽  
Author(s):  
D. S. Arey ◽  
A. M. Petchey ◽  
V. R. Fowler
Keyword(s):  
Nest Building ◽  
Important Influence ◽  
Nest Material ◽  
Significant Preference ◽  
Nest Box ◽  
Nesting Behaviour ◽  
Group 2 ◽  
Building Behaviour ◽  
Group 1

AbstractFarrowing site choice was examined in 40 sows. In group 1, the preference of 16 sows was tested for pre-formed lying areas which incorporated the characteristics of previously observed farrowing nests: a hollow (H), a mattress (M), a nest box (B) and a flat control (C). None of the sows farrowed on C which indicated that choice was based on some evaluation of the lying surface. However, there was no significant preference for the three nest features: H6, M6, B 4. In group 2, C was replaced by a straw area (S). Four different amounts of straw were offered: 18, 9, 4·5 and 2·25 kg with four, four, eight, eight sows on trial at each amount respectively. All the sows farrowed on S at the 18, 9 and 4·5 levels; at 2·25 kg, three farrowed on S and five moved the straw to other lying areas on which they farrowed. The results indicated that the location of nest material has an important influence on farrowing site choice because it allows the performance of nesting behaviour. Although performance of the behaviour was not affected by the amount of straw available, 2·25 kg appeared to be inadequate for a satisfactory nest.

Come on Over: Analyst/Investor Days as a Disclosure Medium

2016 ◽  
Vol 91 (6) ◽  
pp. 1725-1750 ◽  
Author(s):  
Marcus P. Kirk ◽  
Stanimir Markov
Keyword(s):  
Information Content ◽  
Short Duration ◽  
Price Impact ◽  
Senior Management ◽  
Data Availability ◽  
Market Participants ◽  
Temporal Proximity ◽  
Conference Presentations ◽  
Close Temporal Proximity ◽  
Jel Classifications

ABSTRACT Our study introduces analyst/investor days, a new disclosure medium that allows for private interactions with influential market participants. We also highlight interdependencies in the choice and information content of analyst/investor days and conference presentations, a well-researched disclosure medium that similarly allows for private interactions. Analyst/investor days are less frequent, but with longer duration and greater price impact than conference presentations. They are mostly hosted by firms that already have opportunities to interact with investors at conferences, but whose complex and diverse activities make the short duration and rigid format of a conference presentation an imperfect solution to these firms' information problems. Analyst/investor days and conference presentations tend to occur in different quarters, consistent with their competing for the time and attention of senior management. When these two mediums are scheduled in close temporal proximity to each other, analyst/investor days diminish the information content of conference presentations, but not vice versa, consistent with managers' favoring analyst/investor days over conference presentations as a disclosure medium. JEL Classifications: D82; M41; G11; G12; G14. Data Availability: Data are publicly available from the sources identified in the paper.

scholarly journals Nests of the Brazilian squirrel Sciurus ingrami Thomas (Rodentia, Sciuridae)

2005 ◽  
Vol 22 (3) ◽  
pp. 816-818 ◽  
Author(s):  
Cibele A. Alvarenga ◽  
Sônia A. Talamoni
Keyword(s):  
Tree Species ◽  
Minas Gerais ◽  
Side Branch ◽  
Nest Building ◽  
Palm Tree ◽  
High Concentration ◽  
Exotic Tree ◽  
Building Behaviour ◽  
Syagrus Romanzoffiana

Descriptions of Sciurus ingrami Thomas, 1901 nests are not available in the literature. In this study, a survey was made of the distribution of S. ingrami nests in a woodlot located near to the headquarters of the Serra do Caraça Reserve, in state of Minas Gerais, where there is a high concentration of Syagrus romanzoffiana (Chamisso) Glassman palm tree, among other exotic tree species. The nest-building behaviour and the nest characteristics, such as height from the ground, total circumference, diameter of the entrance, and the position of the nest in the tree - in the crown, along the trunk or in a side branch, were described.

Do sows need straw for nest-building ?

1988 ◽  
Vol 28 (2) ◽  
pp. 187 ◽  
Author(s):  
GD Hutson
Keyword(s):  
Animal Welfare ◽  
Operant Conditioning ◽  
Thermal Protection ◽  
Nest Building ◽  
Genetic Adaptation ◽  
The Third ◽  
Significant Difference ◽  
Nesting Behaviour ◽  
Fourth Experiment ◽  
Conditioning Apparatus

The motivation of sows to obtain straw was measured in 4 experiments using operant conditioning apparatus. In the first experiment there was no significant difference in the operant level of response when lifts on a lever produced access to an empty box or a box containing straw. None of the 6 sows, 4 about 10 weeks pregnant and 2 non-pregnant, showed any interest in the straw. In the second experiment variation in motivation to obtain straw was measured by testing pigs for 7 consecutive days every 2 weeks from mating to weaning. All pigs showed little change in lever lifting behaviour, although 2 gilts showed increased responsiveness to straw at farrowing time. In the third experiment 4 sows were allowed to farrow in the test pen with access to the lever and straw box. The sows showed an increase in activity prior to farrowing which coincided with increased manipulation of the lever. The response to straw was variable, although all pigs showed an increase in pawing behaviour. However, in a fourth experiment, 4 control pigs showed similar increases prior to farrowing in activity, lever manipulation, and pawing behaviour when the straw box was empty. The apparent low motivation of sows towards utilisation of straw is discussed in relation to its importance as a key stimulus for nesting behaviour and its role in thermal protection of the piglets, and also in relation to possible absence of appropriate nest-building stimuli, previous experience, genetic adaptation and animal welfare.

scholarly journals Evidence of breeding activity of subadult Turdus thrushes in Argentina

2019 ◽  
Vol 27 (3) ◽  
pp. 149-152
Author(s):  
Exequiel Barboza ◽  
Patricia Capllonch ◽  
Fernando Diego Ortiz ◽  
Alex E. Jahn
Keyword(s):  
Population Dynamics ◽  
Life History ◽  
Bird Species ◽  
Life History Strategies ◽  
Brood Patch ◽  
Breeding Condition ◽  
Different Populations ◽  
Males And Females ◽  
Breeding Seasons ◽  
Subadult Female

AbstractLittle is known about the age at which many Neotropical bird species first attempt to breed. We evaluated the breeding condition of 515 adult and subadult males and females among four species of Turdus thrushes (T. nigriceps, T. chiguanco, T. amaurochalinus and T. rufiventris) in Tucumán, Argentina during three breeding seasons (2015 to 2018). We registered a total of 126 individuals with brood patches and cloacal protuberances, which accounted for 24.5% of thrushes in breeding condition that we sampled. Forty thrushes had a brood patch (31.7% of those in breeding condition), of which 11 were subadults (8.7%). Eighty-six thrushes (68.3%) had a swollen cloacal protuberance, 18 of which were subadults (14.3%). Only a few of the subadults in breeding condition built nests, incubated eggs or raised nestlings. Of 130 nests we found, only 3 belonged to a subadult thrush (in all cases, a subadult female with an adult social mate), one of which was successful. Further research on these patterns among various Neotropical bird species could lead to important insights into the life history strategies that characterize different populations, and how these ultimately affect their population dynamics.

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