The agonistic behaviour of Blue Tits was studied between October and March in 1989/90, 1990/91 and 1991/92 at Ormiston Hall, East Lothian, Scotland. The distribution of breeding sites and individual identities of the resident population were recorded during the spring and early summer of 1990, 1991 and 1992. Resident birds were sexed behaviourally during the breeding season. Birds were captured, in mist nets or at the nest, for colour ringing (to facilitate individual recognition) and for the collection of a range of biometrics including age, wing length, tarsus length, the distance from the bill tip to the back of the skull, weight, bib colour and the extent of white feathering on the brow. The biometry of the study population was described. These data were used to develop a discriminant function by which birds might be assigned a most probable sex on the basis of biometrics. (This work has been published: Scott, G.W., (1993). Sexing members of a Scottish Blue Tit (Parus caeruleus) population in the hand during the winter months. Ringing and Migration, <I>14</I> pp 124-128.) It was demonstrated that a subset of the winter population developed an affinity for a particular feeding area during their first winter, which was close to that area of the study site which became their breeding territory. The agonistic behaviour of the Blue Tits in the vicinity of an artificial food source was recorded and described. Overt physical fighting was found to be rare in the context of the observed interactions, and it was suggested that one or more other factors might be involved in the resolution of agonistic encounters.

The distribution of fitness between group members was investigated by sampling and genotyping around 400 individuals from two study sites in South Africa for 6-12 microsatellite markers. This data was used first, to construct group pedigrees using parentage analysis to assign maternity and paternity to pups; and second, to calculate relatedness coefficients. Parentage analysis showed that up to 84% and 100% of pups were the offspring of dominant males and females respectively, demonstrating that subordinates rarely invested in their own offspring. Breeding success of subordinate males was predictable by the presence or absence of an unrelated opposite sex breeder, whereas all subordinate females appeared subject to suppression by the dominant female. The majority of subordinates accrued substantial indirect fitness from helping in their natal group. Relatedness measurements revealed that natal subordinates of both sexes, have on average, a relatedness of 0.29 to pups (not significantly different from r=0.25, i.e. that between halfsibs). Non-breeding, immigrant males were unrelated to offspring and so gained no direct or indirect fitness from helping, but had a higher chance of obtaining direct fitness in the future either while subordinate or by gaining dominance. In conclusion, direct fitness benefits are distributed strongly in favour of dominants which invest least in care-provision for young. Only a small proportion of subordinate helpers recruit to the dominant breeding population, due to constraints on breeding from suppression by dominants and/or high ecological constraints on successful dispersal. Helping is prevalent, therefore, as a means by which fitness can be acquired indirectly, by providing care for related young in natal groups. The small proportion of males which disperse successfully from their natal group do not acquire indirect fitness from helping but increase the chance of breeding while subordinate and/or inheriting dominance in the future.

I investigated the spatial memory abilities of male rufous hummingbirds (<i>Selasphorus rufus</i>) on their breeding grounds, where birds can be readily trained to feed from artificial flowers presented in two- and three-dimensional arrays. I found that birds use height as a cue when encoding flower locations, preferring to visit taller flowers. Performance in three-dimensional arrays was not however consistently better than in 2-D arrays. I also examined the possibility that hummingbirds follow a fixed flight path when returning to an array of flowers, as has been seen in the Hymenoptera. By manipulating the number of doors by which a bird could enter an arena to feed on an array of flowers, I found some evidence that birds do use systematic movements when relocating rewarding sites. Rufous hummingbirds feed on floral nectar, a resource that varies in time as well as space. To determine whether these birds use time as a cue when foraging, I provided them with an array in which flowers were refilled after intervals of either ten or twenty minute. The birds were able to learn these intervals, as they returned to flowers on or shortly after their expected refill time. I used an analogous experiment to investigate timing abilities in coal tits (<i>Parus ater</i>), a food-storing species, and great tits (<i>P. major</i>), a non food-storing species, in the laboratory. Storers and non-storer might differ in their ability to time intervals due to the demands, on storers, of reliable cache recovery. Coal tits were able to track the availability of rewards in three different locations associated with reward schedules in the 30-120s range. I found no consistent differnces in the abilities of coal tits and great tits to time intervals in the 40-70s range. In conclusion, rufous hummingbirds were shown to use both spatial and temporal cues whilst foraging at flowers. Coal tits and great tits were able to time short intervals in the laboratory, but I found no overall differences in timing behaviour between the two species.

No description available.

Vocal mimicry - the copying of heterospecific sounds - is a widely spread but poorly understood phenomenon. The bowerbird family <i>(Ptilonorhnychidae) </i>are well known for their mimicry with most species incorporating mimicked calls into their elaborate sexual displays. Spotted bowerbirds <i>(Chlamydera maculata), </i>however, despite being competent imitators, do not include mimicry in their sexual displays. Here I discuss the vocal mimicry in this species, including suggestions of a possible function. I considered evidence for four hypotheses previously put forward to explain vocal mimicry. During observational studies I found that spotted bowerbirds preferentially mimic aggressive species and that the rate of mimicry also increases in the presence of such species. This suggests that mimicry may be involved in threat avoidance, as a type of Batesian mimicry. I tested this hypothesis using stuffed mounts of birds representing differing threats to the bowerbird. While there were some differences in species-specific vocalisation, such mounts did not appear to elicit a mimetic response. However, during experimental disturbances at the bower, some birds responded with an increased mimetic rate, supporting the threat avoidance hypothesis. It was evident that there was individual variation in both species-specific and mimetic vocalisation. I explored this variation in terms of duration of bower tenure and individual status. I also examined different ways to estimate the complete mimetic repertoire size. I considered different mechanisms for learning mimicry and showed that bowerbirds do not mimic the most commonly heard birds at their bowers, or the same calls as their relatives or nearest neighbours. Variation in bower design also occurs. In summary, given my data, the most likely function of vocal mimicry in the spotted bowerbird is threat avoidance.

The redbilled quelea <i>Quelea quelea</i> is the most numerous bird in the world. It is found throughout the drier parts of sub-Saharan Africa where it is a serious pest of grain crops. Better management and control of the redbilled quelea as a pest requires a thorough understanding of its migration patterns. This thesis presents three techniques to analyse the migration patterns of redbilled quelea in southern Africa. The genetic structure of redbilled quelea from 32 sites across southern Africa was studied using eight polymorphic microsatellite loci. No evidence of population division was found even though a variety of analysis techniques were used. There was no evidence for regular migration pathways or the existence of a migratory divide. However evidence was found for differential dispersal between the sexes; male quelea dispersed further from their natal flocks than females. In a parentage study, 22.6% of chicks were not related to their social father, while 8.5% of chicks were not related to either of the parents assigned to them by behavioural observations. The redbilled quelea is sexually dimorphic. Across Africa three subspecies have been described based on the variation in male breeding plumage. Two separate techniques were used to analyse this variation: plumage colour was scored using the human eye and colour variation was assessed using the software package Photoshop. Despite a second subspecies having been described for southern Africa, no evidence was found for geographic variation in male breeding plumage patterns. Redbilled quelea migration is determined by the regular patterns of seasonal rainfall. In central southern Africa rainfronts approach from two different directions indicating that a migratory divide could exist for redbilled quelea. The direction preferences of redbilled quelea ready to migrate were tested in the wild using Emlen funnels. Two distinct migration directions were preferred by redbilled quelea indicating the possible presence of a migratory divide.

No description available.

This thesis examines in detail the extent to which individual differences in specific aspects of behaviour in pigs can be characterised as stable personality traits showing consistency across time and context. Behavioural tests were developed to measure aggressiveness, the active/passive responses to challenging situations and flexibility/persistence of behaviour. Aggressiveness: Attack latency in a standardised resident-intruder test situation was found to be consistent across four weeks, and predicted the behaviour when unfamiliar pigs were mixed. Active/passive responses: The reaction to a tonic immobility test (susceptibility to and duration of immobility) predicted ease of handling, speed of movement and reaction speed in an emergence test across time (tested up to an interval of eight weeks). Flexibility/persistence: The persistence to continue an ongoing behaviour or to perform a behaviour once learned to be successful was studied in a distraction task and a reversal task in various maze experiments. Individual differences in the behaviour in the distraction task were consistent across at least 7 weeks and predicted the speed at which pigs mastered a reversal task in a Y-maze. The behaviour in these tests was shown to be consistent across time as well as across situation, which suggests that the differences between individuals may be a reflection of underlying differences in stable personality characteristics. While specific personality traits can be found and assessed, these do not cluster together in pigs, as they appear to in some other species, to form distinctive personality types.

A study was conducted into the spacing behaviour of hens, and the effects of limited space availability on behaviour. The concept of behavioural need and the motivational aspects of spacing behaviour are discussed, along with implications for hen welfare. Familiarity and aggression were the main social factors determining local bird distribution. Familiar birds tended to associate more closely than strangers, though hens preferred visual contact with a stranger to isolation. If given the opportunity, groups of at least 40 hens could recognise each other and would defend their common territory. Within each group, smaller sub-groups tended to occupy core areas within the territory. The effects of familiarity between birds remained evident over several weeks of study. The space around birds was correlated with social status and aggressiveness. In floor pens, increases in group size and stocking density resulted in increased aggression. These increases did not particularly affect the lower ranking birds. Time budgets of hens were affected by space allowance, with small cages restricting behavioural expression. The behaviour patterns most affected were those with elastic demand, but in the smallest cages there was also an effect on food consumption. Behavioural freedom was affected by quite small increases in cage size, while larger increases affected only certain behaviour patterns, e.g. walking. Space increases also affected the way behaviour was performed, allowing more complete expression in more natural ways. In unrestricted environments there was a tendency for group activities to be synchronised, which was increasingly limited as space was restricted. Motivation to synchronise was most evident during feeding. Birds which were unable to feed with the others often showed signs of frustration, with particular individuals tending repeatedly to be the ones excluded.

A study of changes in the subcellular distribution of 4S and5S RNA during oogenesis revealed that in previtellogenic oocytes most 4 and 5S RNA is stored in 42S RNP particles. Accumulation between previtellogenic and white stages is mainly in the soluble fraction, the amount in 42S particles remaining relatively constant. The 42S 4S plus 5S RNA is released between white and full grown stages. Ribosome bound 5$ RNA increases four fold and the soluble non ribosome bound pool decreases although 20% of the total remains there. Over 90% of the 4S RNA is located in the full grown oocyte soluble fraction. The hypothesis that during oogenesis changes in the population of tRNA may control the relative translational efficiency of various mRNAs and that sequestration in 42S RNPs may enable the populations to be kept separate early in oogenesis was tested by cell free translation. No supportive evidence was found. Using two dimensional gel analysis several control systems were found to operate over protein synthesis during oogenesis. Subcellular fractionation enabled identification of four protein classes (soluble, ribosomal, 42S particle and mRNP particle) which are under separate control. Although synthesis of the majority of acidic and neutral proteins (most of which probably fall into the soluble class), was constant throughout oogenesis some proteins which increase or decrease in relative synthesis as well as some detectable only at certain stages were identified. Changes in relative synthesis may occur mainly between previtellogenic and white or white and full grown stages or more gradually over the course of oogenesis. A comparison of protein synthesis in previtellogenic oocytes of Xenopus laevis and Xenopus borealis revealed a number of interspecies differences in electrophoretic mobility of proteins which would be useful markers if a heterologous system was used to study control of protein synthesis during oogenesis.