Budgerigar Case Study
Figure 1. The proportion of time the parakeets spent performing each set of behaviours under control (a), horizontal (b) and vertical (c) conditions
Figure 2. The proportion of time the cockatiels spent performing each set of behaviours under control (a), horizontal (b) and vertical (c) conditions. Although a large amount of time was spent perching, it can be seen here that preening was a dominant behaviour during the control conditions for the cockatiels. This is seen to reduce as the perch arrangement changes.
Figure 3. The proportion of time the budgerigars spent performing each set of behaviours under control (a), horizontal (b) and vertical (c) conditions. This appears to remain similar between arrangements.
Figure 7. The number …show more content…
of new locations made by the parakeets. It is shown that parakeet 1 re-located more than parakeet 2 in the horizontal and vertical arrangements whereas parakeet 2 appeared to re-locate less in horizontal and vertical arrangements compared to the control.
Figure 8.
The number of new locations made by the cockatiels. It appears that there are no obvious changes in the species as a whole in the number of new locations, but individual movements varied widely between experiments, particularly in cockatiels 1, 3, 4, 5 and 6 where an increase in new locations is seen in the horizontal and vertical arrangements.
Figure 9. The number of new locations made by the budgerigars. It can be seen in budgerigars 1, 2 and 4 that new locations were decreased during the horizontal arrangement and then increased during the vertical. However, for budgerigars 3, 5 and 6 the opposite has occurred.
Figure 10. The number of aggressive behaviour expressed by each species during each arrangement. It can be seen that a decrease in aggressive behaviour was expressed by all three species during the horizontal and vertical arrangements in comparison to the …show more content…
control.
The effect of perch arrangement on the behaviour of individuals in a mixed-species aviary
1.0 Introduction
The natural behaviour of birds may be reflected in captive environments, especially in parrots (Kalmer et al., 2010) as the domestication is fairly recent (Meehan et al., 2003). The present study aims to encourage more 'natural ' behaviours in a captive, mixed-species flock of such birds, which are housed in an outdoor aviary, through analysing the effect of perch arrangement on behaviour. It is hypothesised that more active, locomotive behaviour will be expressed when perches are set at different heights possibly due to perching position being a reflection of dominance (McGowen et al., 2006).
2.0 Bird behaviour
The use of birds as companion animals is believed to have begun around 1,400 years ago (Temple, 1992), although some research suggests that parrots have been kept in captivity for as long as 2,500 years (Kalmer et al., 2010). The import and export of exotic species has allowed for the introduction of alien species into many habitats where they would not previously exist (Temple, 1992). However, those birds which remained in captivity and are now born and raised in the UK are widely kept as pets such as psittacid species including the parrot, budgerigar (Melopsittacus undulatus), cockatiel (Nymphicus hollandicus) and parakeet.
2.1 Feeding behaviour
The feeding behaviour of birds varies widely between species in relation to the type and availability of food required. Psittacines in the wild generally have a 'uniform diet ' (Bauck, 1998) which is usually obtained through foraging behaviour but may be influenced by social factors (Bauck, 1998). Time investments into foraging also play an important role as this dictates a large part of the routine of the individual. For example, Crimson Rosella have been found to spend up to 67% of their time foraging and consuming their food (Magrath and Lill, 1985). Similarly, a large amount of time may be spent obtaining edible parts from difficult seeds or nuts (Bauck, 1998). This is important for captive birds as it allows them to reflect natural behaviour which may lead to the implementation of feeding enrichment devices to improve welfare standards in captivity (Bauck, 1998).
2.2 Maintenance behaviour
Maintenance behaviour including preening, allopreening, ruffling feathers, wiping beaks and bathing. The role of preening is primarily hygiene reasons and to maintain the interlocking barbs of feathers, to insure optimum quality of the feathers which is necessary for flight (Macwhirter, 2009). However other functions of preening found throughout animal species may include affirming dominance (Sparks, 1969; Eisenberg, 1981), comforting individuals after conflict (Call et al., 2002), reducing tensions (Baker and Aureli, 2000) and to improve relationships between members of the flock or group (Seyfarth and Cheney, 1984). Allopreening was originally believed to be a method of preening areas which the individual could not reach itself (Harrison, 1965) but has since been understood to have a large social role also (Radford and Plessis, 2006). For example, the more dominant green woodhoopoes in a group may receive higher rates of body allopreening than subordinates and may only return 9.7% of this behaviour (Radford and Plessis, 2006), whereas the subordinates were seen to receive high levels of head allopreening (Radford and Plessis, 2006). This indicates the social importance of allopreening, suggesting that it may be a form of submission or dominance behaviour that may establish relationships between individuals.
2.3 Social interactions
Pair bonds play a large role in the sociality of birds and can be found throughout the bird world. The role of such behaviour may have several functions. Fowler (1995) suggested that birds which remain with the same breeding partner for several breeding seasons may initiate breeding at an earlier stage than new pairs. In the short-lived, monogamous house finch (McGraw and Hill, 2003) it was found that the early breeding pairs that had been together for a number of seasons were able to produce more offspring than new pairs, resulting in higher breeding success (McGraw and Hill, 2003). The pair bond between a male and female penguin is thought to aid with raising offspring in harsh environmental conditions where costs are high (Beaulieu et al., 2009), making it a method of survival.
Some forms of intra and interspecific interactions may indicate dominance and conflicts within a group of birds.
Dominance hierarchies have a large influence on behaviour, yet are necessary to maintain relationships. McGowen et al. (2006) discussed dominance and roosting position in a captive flock of long-tailed tits, indicating that the most subordinate individuals would have to perch on the outer positions of the roost. This has also been seen in the red-winged blackbird where the roosts are structured according to dominance (Weatherhead and Hoysak, 1984). Dominance may also play an important role in aggression. Aggression in birds, especially in captivity, can create welfare issues for keepers and owners if allowed to elevate to situations where birds are getting injured regularly. However, aggression should be understood as a normal element of a bird 's social interactions and can be related to the instinct of natural behaviours such as attracting mates (Ophir and Galef, 2002). However, the costs of aggressive behaviour can be high, such as higher injury risk which may reduce survival (Wingfield et al., 2001), so such behaviour is regulated and used only when a necessity. Aggression may be a natural response to several factors, including hormonal changes through seasons (Marasco et al., 2011), breeding density (Yoon et al., 2012), territory (Hannon and Eason, 1995), resource availability (Vahl and Kingma, 2007), and kinship (Toth et al.,
2009).
2.4 Abnormal behaviour or stereotypies
An important element of ownership of such birds is being able to understand the behaviours of the animal, including which are normal and which are abnormal. This is a crucial part of animal welfare and it has been suggested that 'inappropriate rearing and housing conditions ' may lead to the development of abnormal behaviour (van Hoek and Cate, 1998). Stereotypy behaviour may be found in the form of locomotor, oral or object directed actions (Garner et al., 2006) which are obsessively repeated. In a study by Garner et al. (2003) it was found that individual parrots may spend between 0 and 39% of their active time performing locomotor or oral stereotypy behaviour. Furthermore, the factor which caused said behaviour was also responsible for poor performance in a 'gambling task '. The parrots which expressed higher levels of stereotypies tended to repeat failed attempts at the task rather than altering the method in which it was approached (Garner et al., 2003), suggesting that performing stereotypies may have an impact on other elements of survival such as foraging.
2.5 The present study
The aviary used for the current study consisted of three separate species – the budgerigar, the cockatiel and the red-rumped parakeet. A focus on the intra and interspecific interactions was conducted in this study as well as observations of individual behaviour. Further observations relate to aggression and the expression of stereotypies which indicate welfare issues. This study aims to develop an understanding of bird behaviour and the relationship this shares with the captive environment, through studying individual and grouped species behavioural changes after a change of environment. The main objective is to establish present behaviour within the aviary and compare to behaviour once the environment has been adapted through changing perching. Further objectives include recording aggressive interaction frequency during each environment change, recording the number of new locations made per bird under each environment change and to analyse any stereotypies which may or may not be present and then try to counteract these through the environment changes. It is hypothesised that more active locomotive behaviours will be seen where perches are arranged further apart through height as individuals may have to assert their dominance through holding the 'best ' perching position. The null hypothesis is that no behavioural changes will be found during each perch arrangement.
3.0 Methodology
3.1 Subjects
The subjects in this study were all of the Psittacine family of birds – budgerigars (Melopsittacus undulatus), cockatiels (Nymphicus hollandicus) and red-rumped parakeets (Psephotus haematonotus). The group consisted of three opposite-sex pairs of budgerigar, three opposite-sex pairs of cockatiel and one opposite-sex pair of red-rumped parakeets. Of these, two budgerigars were related as were two of the cockatiels, but the others were all non-related.
3.2Enclosure
The birds were kept in a hexagonal, outdoor aviary with an indoor and outdoor area. The outdoor area was the main area used as a nesting female budgerigar prevented other birds from accessing the indoor area during observations. The birds were subject to ambient temperatures and environmental conditions including heavy rain, strong winds and snow. Perching in the aviary consisted of one, long perch which measured the entire width of the aviary and was placed at the bottom of the roof to allow shelter at night. Additional perches were one apple tree branch that allowed for perching nearer to the base of the aviary and one in the outdoor area to allow for bathing in rain and gnawing. Natural lighting was used during observations.
3.3 Feeding
Feeding consisted of commercial aviary bird seed alongside fresh vegetables and fruit which are given daily. Time of feeding generally occurs around 1pm each day and, at this time, the introduction of fresh apple tree branches and twigs took place for gnawing and additional perching in the outdoor area. The feed was accessible to the birds at all times and was only added to during feeding times. Drinking water was also available at all times.
3.4 Perch arrangements
The experiment involved three perch arrangements -control, experiment one (horizontal) and experiment two (vertical). The control consisted of the original set up in the aviary – see section 3.2. The horizontal arrangement was set up to provide perching that was all at the same height. Three perches were installed around 1.5 metres from the ground in the aviary at various angles and positions. The vertical arrangement involved the same three perches being re-arranged to different heights approximately 30-50cm apart in height at various angles and positions. Feed and water locations remained the same to the control and feed was provided at the same time of day. No other changes were made to the aviary or the routine of the birds during observations.
3.5 Data collection
Filming of the control, horizontal and vertical arrangements was completed between 11am and 12.30pm over three days of a week. Three hours of data was collected per set-up. During this time, the birds were subject to any 'normal ' disturbances including wild birds, passing traffic and aeroplane noise. Filming took place outside of the aviary with a non-invasive camera hidden in vegetation. Once films had been collected, the films were analysed and data was recorded at 15 second intervals for each hour of video for each individual. Behaviours recorded included perching, locomotive, preening, social, feeding and sleeping with the addition of nesting behaviour for the single female budgerigar. Also recorded was the number, type and victims of aggressive interactions as well as which individual performed the aggression. Furthermore, the number of new locations – where an individual had moved to a different perch or area – were recorded to analyse activity levels in response to the different perch arrangements.
4.0 Results
Data was entered into Microsoft Excel and Minitab 15 to be analysed. Due to the large amounts of data recorded, results are generalised into groups of behaviour rather than specific behaviours. Tables 1, 2 and 3 contain a summary of the data for the each of the species involved in the experiment. It should be noted at this time that sleeping and nesting behaviour have been combined to allow the nesting female budgerigar to be included in the results – percent of time sleeping for the budgerigars is not actual time spent sleeping, but includes the fact that the female was nesting for a majority of observations.
Table 1. The percent of time the parakeets spent performing each behaviour. The main differences are shown in the vertical arrangement where an increase of almost 8% of time is spent feeding. Type of behaviour | Control | Horizontal | Vertical | Perching | 80.75% | 85.99% | 76.60% | Locomotive | 2.16% | 1.87% | 2.43% | Preening | 8.55% | 3.01% | 4.51% | Social | 0.00% | 0.00% | 0.00% | Feeding | 8.55% | 6.68% | 16.46% | Sleeping and nesting | 0.00% | 0.00% | 0.00% | Mating | 0.00% | 0.00% | 0.00% |
Table 2. The percent of time the cockatiel population spent performing each behaviour type during each arrangement. The main changes are shown in the preening row where a drop of over 10% of time spent performing preening has been expressed in the horizontal and vertical arrangements. Type of behaviour | Control | Horizontal | Vertical | Perching | 67.73% | 64.06% | 56.11% | Locomotive | 2.77% | 2.28% | 4.17% | Preening | 22.76% | 8.69% | 9.54% | Social | 0.37% | 0.00% | 0.14% | Feeding | 2.45% | 14.85% | 8.66% | Sleeping and nesting | 3.70% | 12.70% | 20.56% | Mating | 0.00% | 0.00% | 0.00% |
Table 3. The percentage of time the budgerigars spent performing each behaviour type during observations. Very subtle changes in behaviour are shown, including a slight increase in preening behaviour in both the horizontal and vertical arrangements. Type of behaviour | Control | Horizontal | Vertical | Perching | 63.29% | 62.19% | 61.41% | Locomotive | 5.30% | 4.23% | 4.26% | Preening | 6.90% | 10.34% | 8.70% | Social | 4.87% | 2.50% | 3.10% | Feeding | 4.29% | 6.30% | 6.16% | Sleeping and nesting | 14.40% | 14.25% | 16.18% | Mating | 0.00% | 0.22% | 0.00% |
Data was then put into graphs to show the proportionate amount of time each species displayed each behaviour under each arrangement. Figure 1 shows this for the parakeets, figure 2 for the cockatiels and figure 3 for the budgerigars. The total number of possible behaviours for each arrangement was calculated at 626 for the control, 614 for the horizontal and 720 for the vertical due to technical issues with some recordings. Therefore, percentages are relative to the appropriate total of possible behaviours to maintain reliability of results.
The individuals must now be analysed to see if changes in behaviour occurred between arrangements. The same consideration has been made for the total number of possible behaviours in order to create more accurate results, so percentages are relative to the possible total number of behaviours for each arrangement. To analyse individuals, changes between time spent performing behaviours will be looked at under each arrangement.
Table 4. The percentage of time spent performing each behaviour type by the individual parakeets during each arrangement. Few changes have occurred, except for a slight increase in time spent feeding from both individuals during the vertical experiment. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Parakeet 1 | | | | | | | | C | 79.39% | 2.56% | 8.15% | 0.00% | 9.90% | 0.00% | 0.00% | H | 86.81% | 2.77% | 1.30% | 0.00% | 9.90% | 0.00% | 0.00% | V | 79.17% | 2.50% | 2.50% | 0.00% | 15.83% | 0.00% | 0.00% | Parakeet 2 | | | | | | | | C | 82.11% | 1.76% | 8.95% | 0.00% | 7.19% | 0.00% | 0.00% | H | 85.18% | 0.98% | 4.72% | 0.00% | 8.96% | 0.00% | 0.00% | V | 74.03% | 2.36% | 6.53% | 0.00% | 17.08% | 0.00% | 0.00% |
Table 5. The percentage of time each individual cockatiel spent performing each type of behaviour. It appears that preening, in general, decreased during the horizontal and vertical arrangements and feeding was generally more frequent during the horizontal arrangement. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Cockatiel 1 | | | | | | | | C | 68.37% | 5.43% | 20.93% | 1.28% | 0.96% | 3.04% | 0.00% | H | 69.22% | 2.28% | 5.86% | 0.00% | 19.06% | 3.58% | 0.00% | V | 50.69% | 4.86% | 11.81% | 0.42% | 12.50% | 18.75% | 0.00% | Cockatiel 2 | | | | | | | | C | 67.89% | 3.83% | 24.44% | 0.00% | 1.28% | 1.28% | 0.00% | H | 56.35% | 2.28% | 14.82% | 0.00% | 19.71% | 7.65% | 0.00% | V | 45.69% | 7.78% | 8.89% | 0.00% | 8.33% | 28.47% | 0.00% | Cockatiel 3 | | | | | | | | C | 74.12% | 0.96% | 19.81% | 0.32% | 4.15% | 0.64% | 0.00% | H | 65.96% | 1.63% | 9.93% | 0.00% | 14.33% | 8.14% | 0.00% | V | 60.97% | 3.47% | 8.33% | 0.14% | 4.86% | 18.47% | 0.00% | Cockatiel 4 | | | | | | | | C | 76.20% | 4.95% | 15.18% | 0.32% | 2.88% | 0.48% | 0.00% | H | 77.20% | 3.42% | 7.65% | 0.00% | 12.54% | 13.84% | 0.00% | V | 63.47% | 2.92% | 7.64% | 0.14% | 15.14% | 15.00% | 0.00% | Cockatiel 5 | | | | | | | | C | 74.12% | 0.96% | 19.81% | 0.32% | 4.15% | 0.64% | 0.00% | H | 65.96% | 1.63% | 9.93% | 0.00% | 14.33% | 8.14% | 0.00% | V | 60.97% | 3.47% | 8.33% | 0.14% | 4.86% | 18.47% | 0.00% | Cockatiel 6 | | | | | | | | C | 45.69% | 0.48% | 36.42% | 0.00% | 1.28% | 16.13% | 0.00% | H | 49.67% | 2.44% | 3.91% | 0.00% | 9.12% | 34.85% | 0.00% | V | 54.86% | 2.50% | 12.22% | 0.00% | 6.25% | 24.17% | 0.00% |
Due to the problem of the nesting female budgerigar, an extra column for percentage of time spent nesting is shown in table 6. Obviously this will only be relevant for budgerigar number 6, but it may be the case that time spent nesting or performing other behaviours changed according to the different arrangements. The nesting column for the other five budgerigars will be left blank as it is not relevant for all of the individuals.
Table 6. The percentage of time spent performing each behaviour type by each individual budgerigar. There appear to be no obvious changes in relation to each experiment, except a possible slight increase in preening during horizontal and vertical arrangements. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Nesting | Budgerigar 1 | | | | | | | | | C | 82.75% | 8.79% | 4.47% | 0.16% | 3.83% | 0.00% | 0.00% | | H | 78.50% | 7.82% | 7.82% | 0.00% | 6.84% | 2.12% | 0.00% | | V | 82.78% | 7.22% | 7.22% | 0.97% | 5.28% | 0.00% | 0.00% | | Budgerigar 2 | | | | | | | | | C | 74.44% | 8.15% | 6.39% | 3.35% | 5.43% | 0.00% | 0.00% | | H | 82.08% | 6.19% | 5.54% | 1.47% | 4.72% | 0.00% | 0.00% | | V | 77.78% | 6.39% | 5.56% | 4.17% | 5.14% | 0.97% | 0.00% | | Budgerigar 3 | | | | | | | | | C | 66.93% | 2.56% | 12.14% | 11.34% | 3.35% | 0.00% | 0.00% | | H | 66.29% | 2.61% | 16.78% | 6.03% | 7.65% | 0.00% | 0.65% | | V | 72.22% | 4.31% | 13.06% | 4.31% | 5.14% | 1.81% | 0.00% | | Budgerigar 4 | | | | | | | | | C | 73.00% | 6.39% | 9.74% | 2.40% | 6.87% | 1.60% | 0.00% | | H | 58.31% | 3.58% | 21.50% | 0.81% | 11.56% | 4.23% | 0.00% | | V | 61.53% | 4.44% | 13.19% | 3.89% | 9.72% | 5.28% | 0.00% | | Budgerigar 5 | | | | | | | | | C | 73.00% | 4.95% | 7.19% | 11.66% | 3.19% | 0.00% | 0.00% | | H | 66.29% | 4.07% | 9.93% | 6.68% | 3.75% | 0.00% | 0.65% | | V | 72.22% | 2.92% | 11.94% | 4.17% | 5.42% | 7.36% | 0.00% | | Budgerigar 6 | | | | | | | | | C | 9.58% | 0.96% | 1.44% | 0.32% | 3.04% | 0.00% | 0.00% | 84.82% | H | 12.87% | 1.14% | 3.58% | 0.00% | 3.26% | 0.00% | 0.00% | 79.15% | V | 5.97% | 0.28% | 4.72% | 1.11% | 6.25% | 0.00% | 0.00% | 81.67% |
The data from tables 4, 5 and 6 is shown below in graphs which are separated according to each arrangement. Individuals are represented by each column and behaviours are indicated by the separate colours in each column. Nesting only relates to budgerigar 6, for all others, this is sleep.
Further to studying specific behaviours, it was also recorded how often a new location was made by each bird. A new location was defined as an individual physically leaving a perching, sitting or climbing position and re-locating to a completely new area. This may have been changing perches, moving from perch to climbing on the wire or moving from perch to feeding station, as well as other position changes. The results of this data is shown in figures 7, 8 and 9.
Aggressive interactions were also recorded in relation to species performing the aggression during each arrangement. This data is displayed in figure 10.
5.0 Statistical analysis
Statistical analysis was performed in both Microsoft Excel and Minitab 15. Using t-tests, the behaviours were analysed to see individual behavioural changes between arrangements. It was found that cockatiel 1 (p-value = 0.0358) and cockatiel 5 (p-value = 0.0489) showed significantly difference levels of preening behaviour between the horizontal and vertical arrangements. Furthermore, budgerigar 2 displayed significantly different amounts locomotive behaviour between the control and horizontal arrangements (p-value=0.0496). In addition, t-tests were used to assess changes in the species behaviours under each arrangement and it was found that the preening behaviour of the parakeets was significantly different between the horizontal and the vertical arrangements (p-value = 0.0467) and that the feeding behaviour of the budgerigars was also significantly different in the same two arrangements (p-value = 0.0360).
To establish an analysis of the interaction between the individual bird and the perch arrangement, a 2-way ANOVA was used. Each behaviour was assessed and it was found that no statistical difference was found between arrangements, apart from a p-value of 0.056 for social behaviour. The significant difference here was found to be between budgerigars 3 and 5 in relation to the control (p-value = 0.0001 for both individuals). Another 2-way ANOVA was used to indicate an interaction between the different species and their behavioural changes during each perch arrangement. It was found that the only significant statistical difference here was a p-value of 0.058 for feeding behaviour. This difference was found in the behaviour of budgerigar 6 who was nesting at the time so this is not entirely relevant as her behaviour is biased towards her breeding behaviour.
T-tests were used again to indicate any changes in new location frequency between arrangements. It was found that no statistical difference was found between the number of new locations and the arrangement of the perches. Furthermore, no significant difference was found in the aggressive interaction frequency between arrangements, showing that each arrangement had little or no effect on such occurrences.
6.0 Discussion
From the results, it is possible to say that very few significant differences were found in behaviour between each arrangement. However, small differences were seen when looking at the separate species and the individuals even if these were not all statistically significant. Firstly, a slight decrease in preening was expressed (p-value = 0.0469) by the parakeets throughout the experiments (C – 8.55%, H – 3.01%, V – 4.51%) which was also seen in the cockatiels (C – 22.76%, H – 8.69%, V – 9.54%), in particular cockatiels 1 (p-value = 0.0358) and 5 (p-value = 0.0486) between the horizontal and vertical arrangements. Verbeek (1972) found that the annual percentage of time spent preening in magpies was 4.6% in males and 4.2% in females, therefore, it could be said that, during the control, preening behaviours were bordering on stereotypical as some individuals spent between a fifth and a quarter of their time preening. The preening behaviour may have also been influenced by the feeding routine (Savory and Kostal, 1996) whereby birds were anticipating fresh feed being introduced. However, Savory and Kostal (1996) found that preening replaced stereotypical behaviour post-feeding in chickens, indicating that this may not be the reason for higher levels of this behaviour during the present study.
The results may suggest that the control arrangement of the perches was habitual to the birds so other behaviours were limited and boredom was high, whereas during the horizontal and vertical arrangements a newly laid out environment may have been more stimulatory, which has also been suggested by Little and Sommer (2002). However, this was not reflected in all of the results as more active locomotive behaviours remained at a similar level through each arrangement, apart from budgerigar 2. This individual was seen to perform significantly more locomotive behaviour in the control when compared the horizontal arrangement (p-value = 0.0496). This may be because of the horizontal arrangement being all on one level so the bird had to move around a lot more to be able to access food. However, this has only been seen in the one individual so does not relate to the aviary as a whole. Nonetheless, by using the change of environment as a form of enrichment, the present study relates to other previous research such as Bubier (1996). Bubier found that the presence or absence of enrichment directly affected the time budgets of laying hens and that an unenriched environment caused time spent performing particular behaviours to increase, including preening. This suggests that a change in environment provided mental stimulation for the birds in the present study, perhaps decreasing the risk of development of stereotypies and abnormal behaviours.
It was also seen that feeding behaviour increased, although this was not statistically significant, in the parakeets during the vertical (C – 8.55%, H – 6.68%, V- 16.46%) and in the cockatiels during the horizontal (C – 2.45%, H – 14.85%, V – 8.66%),. This may have been due to the feeding stations being closer to certain perches which each species appeared to have a preference to. For example, the cockatiels favoured higher perches, which may have caused the cockatiels to unintentionally be perched closer to a feeding station during the horizontal, therefore making the station more accessible and reducing the costs of feeding. Kacelnik (1984) formed a similar theory as he found that starlings were more likely to travel further to find food if the food was more plentiful as it replenishes the costs of travelling to the food from a central point. This may have been reflected in the aviary as the location of feed stations may have been further away for the cockatiels during the vertical, but closer for the cockatiels during the horizontal. However, as the enclosure in the present study is probably not large enough to allow for travel costs, this may not be relevant. It was also found that there was a significant difference in the feeding behaviour of the budgerigars in the horizontal and vertical arrangements (p-value = 0.0360), indicating a possible similarity between the behaviour of the budgerigars and the behaviour of the cockatiels.
Feeding behaviour of the birds in the aviary differs from studies of natural behaviour as discussed by Magrath and Lill (1985). Compared to the 67% of time spent completing food related activities in Crimson Rosella (Magrath and Lill, 1985), the birds in the present study spent a maximum of 17.08% (parakeet 2 during the vertical arrangement). This suggests that the effect of captive availability of food decreases the need for foraging which would otherwise consume a large amount of time. This has, in turn, given the birds free time in which other behaviours can be expressed. However, this has little relation to the perching arrangement.
Sleeping behaviour in the cockatiels appeared to increase during the horizontal and vertical arrangements (C – 3.70%, H – 12.70%, V – 20.56%). Although this was not statistically significant, it may be an indication that a possible increase in mental stimulation caused an increase in sleeping behaviour for relatively inactive individuals due to an increase in brain activity. Nonetheless, there appears to be limited research in this area including Tagney (1973) who found that an enriched environments caused rats to sleep for longer. This, however, may not be the case as the weather conditions played a factor, particularly in the vertical arrangement where temperatures were below 0ºC and snow was present. It has been discussed by Berger and Phillips (1995) that sleep is beneficial in cold weather as it has thermoregulatory benefits. This may have been the cause of the increased sleeping during the horizontal and vertical arrangements rather than an effect of the arrangements themselves.
Very slight differences were found in the behaviour of the budgerigars throughout each arrangement. The budgerigars were found to be the most social and performed the widest variety of behaviours including regular allopreening, beaking and mating. This diverse repertoire of behaviours perhaps may be the reason the changes in perch arrangement did not significantly affect the budgerigar behaviour as they were already very active and diverse within the environment. However, it is possible that a slight increase in preening behaviour found in budgerigars 1 (C- 4.47%, H – 7.82%, V – 7.22%) and 4 (C – 9.74%, H – 21.50%, V – 13.19%) during the horizontal and vertical was caused by the new arrangements. There may have been a decrease in social behaviour also by budgerigars 3 (C- 11.34%, H – 6.03%, V – 4.31%) and 5 (C – 11.66%, H – 6.68%, V – 4.17%). These individuals had a pair bond which has been previously discussed as beneficial for breeding purposes and survival (Beaulieu et al., 2009). However, the social interactions of the pair where the female was presently nesting, budgerigars 1 (male) and 6 (nesting female), were less frequent than pairs who were not currently breeding. Although it is obvious that most time and energy of the breeding female was spent nesting in all three arrangements, during the vertical arrangement a slight increase in social activity occurred between the breeding pair (male social activity C – 0.16%, H – 0.00%, V – 0.97%, female social activity C – 0.32%, H – 0.00%, V – 1.11%). However, this is such a slight difference and cannot be said to be significant.
The frequency of aggressive interactions during each arrangement, as seen in figure 10, decreased from the control to the horizontal and vertical. Little and Sommer (2002) found similar results in Langur monkeys where a new environment caused a decrease in aggressive interactions due to increased opportunity for dispersal due to a larger environment. This is a positive change within the social arrangement of the aviary as it could be said that welfare and social stability have been improved. This may be due to the environment being more stimulatory or that there is a larger number of options of perching location so that victims can escape the aggressors. Cornetto et al. (2001) found a similar change when walls were introduced to chicken enclosures. When the enclosure was separated by walls, aggression decreased as the environment provided more areas for individuals to distance themselves from aggressors, and when no cover was provided aggression increased. Thus it could be said that by increasing the complexity of the environment, the frequency of aggressive interactions may decrease.
Limitations of the present study include a disproportionate number of individuals representing each species, as only two parakeets were used in this compared to six cockatiels and budgerigars. This means that more data was available for two species and only a small amount for one species, making comparisons and changes less reliable. However, due to a lack of resources this was a problem which was difficult to overcome. A main limitation was budgerigar 6 nesting during observations. This may have triggered unusual behaviours in the social group as tensions and conflicts may have been raised, so results may be biased for this reason. Furthermore severe weather conditions could have caused biased behaviours, such as an increase in sleeping. Freezing temperatures and heavy snowfall could have contributed to this, particularly in the vertical arrangement as during the control the weather was still cold but it was sunny. Additionally, a lack of comparison with other aviaries could have caused results and conclusions that are only relevant to the aviary in the present study rather than information that can be utilised by bird owners. However, there is plenty of research that supports the theory that changing the environment can improve the behaviour and welfare of captive animals.
For future research, this study could be performed on several different aviaries and results compared to see if general changes are found in multiple enclosures rather than just the one. Furthermore, this could be utilised to assess different species reaction to changing perch arrangements, particularly in relation to dominance. The study by McGowen et al. (2006) could be recreated in domestic species like the cockatiel to see whether a relationship between dominance and choice of perch is seen. This could then be related to aggressive interactions, to see if taking away or adding a particular perching location affects the levels of aggression. This would be beneficial for welfare and would enable a deeper understanding of the mechanisms involved in captive species in order to make husbandry easier.
In conclusion, the results of this study indicate that there may be a relationship between perch arrangement and behaviour in a mixed-species aviary. Although differences are not all significant, it could be said that with more research and further studies into different species, the arrangement of perches could be utilised to discourage individuals who may be performing repetitive stereotypical behaviours as well as generally improve the welfare of caged psittacid species by promoting a wider variety of behaviours and to provide mental stimulation for birds that may otherwise perform boredom behaviours.
7.0 References
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Bauck, L., 1998. Psittacine diets and behavioural enrichment. Seminars in Avian and Exotic Pet Medicine, Vol. 7 (3) p135-140
Berger, R.J., and Phillips, N.H., 1995. Energy conservation and sleep. Behavioural Brain Research, Vol. 69 p65-73
Call, J., Aureli, F., and de Waal, F.B.M., 2002. Postconflict third-party affiliation in stumptailed macaques. Animal Behaviour, Vol. 63 (2) p209-216
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Fowler, G.S., 1995. Stages of age-related reproductive success in birds: simultaneous effects of age, pair-bond duration and reproductive experience. Integrative and Comparative Biology, Vol. 35 (4) p318-328
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Hannon, S.J., and Eason, P., 1995. Colour bands, combs and coverable badges in willow ptarmigan. Animal Behaviour, Vol. 49 p53-62
Harrison, C., 1965. Allopreening as agnostic behaviour. Behaviour, Vol. 24 p161-209
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Kalmer, I.D., Janssens, G.P.J., and Moons, C.P.H., 2010. Guidelines and ethical considerations for housing and management of Psittacine birds used in research. Institute for Laboratory Animal Research, Vol. 51 (4) p409-423
Little. K.A. And Sommer, V., 2002. Change of enclosure in Langur monkeys: implications for the evaluation of environmental enrichment. Zoo Biology, Vol. 21 p549-559
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Marasco, V., Fusani, L., Dessi-Fulgheri, F., and Canoine, V., 2011. Non-migratory stonechats show seasonal changes in the hormonal regulation of non-seasonal aggression. Hormones and Behaviour, Vol. 60 p414-419
Margrath, R.D., and Lill, A., 1985. Age-related differences in behaviour and ecology of Crimson Rosellas, Platycercus elegans, during the non-breeding season. Australian Wildlife Research, Vol. 12 (2) p299-306
McGowan, A., Sharp, S.P., Simeoni, M., and Hatchwell, B.J., 2006. Competing for position in the communal roosts of long-tailed tits. Animal Behaviour, Vol. 72 p1035-1043
McGraw, K.J., and Hill, G.E., 2003. Mate attentiveness, seasonal timing of breeding and long-term pair bonding in the house finch (Carpodacus mexicanus). Behaviour, Vol. 141 p1-13
Meehan, C.L., Millam, J.R., and Mench, J.A., 2003. Foraging opportunity and increased physical complexity both prevent and reduce psychogenic feather picking by young Amazon parrots. Applied Animal Behaviour Science, Vol. 80 (1) p71-85
Ophir, A.G., and Galef, B.G., Female Japanese quail that 'eavesdrop ' on fighting males prefer losers to winners. Animal Behaviour, Vol. 66 (2) p399-407
Radford, N.A., and Plessis, M.A.D, 2006. Dual function of allopreening in the cooperatively breeding green woodhoopoe, Phoeniculus purpureus. Behavioural Ecology and Sociobiology, Vol. 61 (2) p221-230
Savory, C.J., and Kostal, L., 1996. Temporal patterning of oral stereotypies in restricted-fed fowls: 1. investigations with a single daily meal. International Journal of Comparative Psychology, Vol. 9 (3) p117-139
Seyfarth, R.M., and Cheney, D.L., 1984. Grooming, alliances and reciprocal altruism in vervet monkeys. Nature, Vol. 308 p541-543
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Toth, Z., Bokoney, V., and Lendvai, A.Z., 2009. Kinship and aggression: do house sparrows spare their relatives? Behavioural Ecology and Sociobiology, Vol. 63 -1189-1196
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Yoon, J., Sillett, T.S., Morrison, S.A. And Ghalambor, C.K., 2012. Breeding density, not life history, predicts interpopulation differences in territorial aggression in a passerine bird. Animal Behaviour, Vol. 84 (3) p515-521
8.0 Appendices
Appendix 1
Summary of email communication between student and project leader (Mark Orminston) regarding data collection – 11/10/2012
Have you heard of time budgets and ethograms? If not look them up in google (search: time budget animal behaviour). This might be the best approach.So it would be like what you have suggested, but you would do a count every 10 seconds or so to see which bird is where. This would give you a % of time spent on each perch for each bird involved over the total study period (30 mins?) - so it is important to know how much time the birds did not spend on the perches as well as how much time they did. Then you would replicate this to get a more accurate time budget. Be sure that you can identify individuals.Try to find examples of other people doing similar research to help you with ideas.
Appendix 2
Summary of email communication between student and lecturer (Kayleigh Liddell) regarding literature review – 8/11/2012
Appendix 3
Summary of email communication between student and Mark Orminston regarding data collection – 18/12/2012
Its a good start. You would need to create an ethogram, which is a table defining each behaviour in detail - for example, exactly what is 'resting '. Should you be noting the position of the bird with respect to the perches too?My concern is how you will collect continuous data for each bird (i.e. counting each behaviour) without spending 100 's of hours watching video footage. I don 't think its possible. So what I would suggest is that you use interval sampling, so you take a visual snapshot of what each bird is doing every 30 seconds. But before going forwards with this idea we need to establish a couple things:1) how many aggressors are there? Are they all squabbling or is it just one or two? Potentially you could do continuous sampling, if you are just looking at 2-3 birds2) how frequent is the aggressive behaviour? If it is as seldom as once every 5 minutes we could miss all the aggressive behaviours if we are doing interval sampling.
The problem with taking a photo every 30 seconds, is that its one still image, and you cannot infer all behaviours from that image. I think the solution is for you to download VLC media player (its free). This is an excellent piece of software that will let you watch your videos frame by frame (or in slow motion). No need to watch the whole video, I would click on every 30 second interval one at a time, and just check a few frames either side of that interval frame to double check what each bird is doing. Ideally you would track each budgie, but if not, just record what each one is doing (number them 1-8 each time, it doesn 't matter if they don 't keep the same number) and at the end we will take an average of what they were doing. We wont be able to say, for example, Budgie number 5 was less aggressive after the change of perch height, but we will be able to say, for example, budgies showed less aggression and more preening behaviour, but similar amounts of resting behaviour on average in response to the new perch configuration.Does this sound like a good plan? If you need a better camera, you might be able to burrow one from college.
Figure 2. The proportion of time the cockatiels spent performing each set of behaviours under control (a), horizontal (b) and vertical (c) conditions. Although a large amount of time was spent perching, it can be seen here that preening was a dominant behaviour during the control conditions for the cockatiels. This is seen to reduce as the perch arrangement changes.
Figure 3. The proportion of time the budgerigars spent performing each set of behaviours under control (a), horizontal (b) and vertical (c) conditions. This appears to remain similar between arrangements.
Figure 7. The number …show more content…
of new locations made by the parakeets. It is shown that parakeet 1 re-located more than parakeet 2 in the horizontal and vertical arrangements whereas parakeet 2 appeared to re-locate less in horizontal and vertical arrangements compared to the control.
Figure 8.
The number of new locations made by the cockatiels. It appears that there are no obvious changes in the species as a whole in the number of new locations, but individual movements varied widely between experiments, particularly in cockatiels 1, 3, 4, 5 and 6 where an increase in new locations is seen in the horizontal and vertical arrangements.
Figure 9. The number of new locations made by the budgerigars. It can be seen in budgerigars 1, 2 and 4 that new locations were decreased during the horizontal arrangement and then increased during the vertical. However, for budgerigars 3, 5 and 6 the opposite has occurred.
Figure 10. The number of aggressive behaviour expressed by each species during each arrangement. It can be seen that a decrease in aggressive behaviour was expressed by all three species during the horizontal and vertical arrangements in comparison to the …show more content…
control.
The effect of perch arrangement on the behaviour of individuals in a mixed-species aviary
1.0 Introduction
The natural behaviour of birds may be reflected in captive environments, especially in parrots (Kalmer et al., 2010) as the domestication is fairly recent (Meehan et al., 2003). The present study aims to encourage more 'natural ' behaviours in a captive, mixed-species flock of such birds, which are housed in an outdoor aviary, through analysing the effect of perch arrangement on behaviour. It is hypothesised that more active, locomotive behaviour will be expressed when perches are set at different heights possibly due to perching position being a reflection of dominance (McGowen et al., 2006).
2.0 Bird behaviour
The use of birds as companion animals is believed to have begun around 1,400 years ago (Temple, 1992), although some research suggests that parrots have been kept in captivity for as long as 2,500 years (Kalmer et al., 2010). The import and export of exotic species has allowed for the introduction of alien species into many habitats where they would not previously exist (Temple, 1992). However, those birds which remained in captivity and are now born and raised in the UK are widely kept as pets such as psittacid species including the parrot, budgerigar (Melopsittacus undulatus), cockatiel (Nymphicus hollandicus) and parakeet.
2.1 Feeding behaviour
The feeding behaviour of birds varies widely between species in relation to the type and availability of food required. Psittacines in the wild generally have a 'uniform diet ' (Bauck, 1998) which is usually obtained through foraging behaviour but may be influenced by social factors (Bauck, 1998). Time investments into foraging also play an important role as this dictates a large part of the routine of the individual. For example, Crimson Rosella have been found to spend up to 67% of their time foraging and consuming their food (Magrath and Lill, 1985). Similarly, a large amount of time may be spent obtaining edible parts from difficult seeds or nuts (Bauck, 1998). This is important for captive birds as it allows them to reflect natural behaviour which may lead to the implementation of feeding enrichment devices to improve welfare standards in captivity (Bauck, 1998).
2.2 Maintenance behaviour
Maintenance behaviour including preening, allopreening, ruffling feathers, wiping beaks and bathing. The role of preening is primarily hygiene reasons and to maintain the interlocking barbs of feathers, to insure optimum quality of the feathers which is necessary for flight (Macwhirter, 2009). However other functions of preening found throughout animal species may include affirming dominance (Sparks, 1969; Eisenberg, 1981), comforting individuals after conflict (Call et al., 2002), reducing tensions (Baker and Aureli, 2000) and to improve relationships between members of the flock or group (Seyfarth and Cheney, 1984). Allopreening was originally believed to be a method of preening areas which the individual could not reach itself (Harrison, 1965) but has since been understood to have a large social role also (Radford and Plessis, 2006). For example, the more dominant green woodhoopoes in a group may receive higher rates of body allopreening than subordinates and may only return 9.7% of this behaviour (Radford and Plessis, 2006), whereas the subordinates were seen to receive high levels of head allopreening (Radford and Plessis, 2006). This indicates the social importance of allopreening, suggesting that it may be a form of submission or dominance behaviour that may establish relationships between individuals.
2.3 Social interactions
Pair bonds play a large role in the sociality of birds and can be found throughout the bird world. The role of such behaviour may have several functions. Fowler (1995) suggested that birds which remain with the same breeding partner for several breeding seasons may initiate breeding at an earlier stage than new pairs. In the short-lived, monogamous house finch (McGraw and Hill, 2003) it was found that the early breeding pairs that had been together for a number of seasons were able to produce more offspring than new pairs, resulting in higher breeding success (McGraw and Hill, 2003). The pair bond between a male and female penguin is thought to aid with raising offspring in harsh environmental conditions where costs are high (Beaulieu et al., 2009), making it a method of survival.
Some forms of intra and interspecific interactions may indicate dominance and conflicts within a group of birds.
Dominance hierarchies have a large influence on behaviour, yet are necessary to maintain relationships. McGowen et al. (2006) discussed dominance and roosting position in a captive flock of long-tailed tits, indicating that the most subordinate individuals would have to perch on the outer positions of the roost. This has also been seen in the red-winged blackbird where the roosts are structured according to dominance (Weatherhead and Hoysak, 1984). Dominance may also play an important role in aggression. Aggression in birds, especially in captivity, can create welfare issues for keepers and owners if allowed to elevate to situations where birds are getting injured regularly. However, aggression should be understood as a normal element of a bird 's social interactions and can be related to the instinct of natural behaviours such as attracting mates (Ophir and Galef, 2002). However, the costs of aggressive behaviour can be high, such as higher injury risk which may reduce survival (Wingfield et al., 2001), so such behaviour is regulated and used only when a necessity. Aggression may be a natural response to several factors, including hormonal changes through seasons (Marasco et al., 2011), breeding density (Yoon et al., 2012), territory (Hannon and Eason, 1995), resource availability (Vahl and Kingma, 2007), and kinship (Toth et al.,
2009).
2.4 Abnormal behaviour or stereotypies
An important element of ownership of such birds is being able to understand the behaviours of the animal, including which are normal and which are abnormal. This is a crucial part of animal welfare and it has been suggested that 'inappropriate rearing and housing conditions ' may lead to the development of abnormal behaviour (van Hoek and Cate, 1998). Stereotypy behaviour may be found in the form of locomotor, oral or object directed actions (Garner et al., 2006) which are obsessively repeated. In a study by Garner et al. (2003) it was found that individual parrots may spend between 0 and 39% of their active time performing locomotor or oral stereotypy behaviour. Furthermore, the factor which caused said behaviour was also responsible for poor performance in a 'gambling task '. The parrots which expressed higher levels of stereotypies tended to repeat failed attempts at the task rather than altering the method in which it was approached (Garner et al., 2003), suggesting that performing stereotypies may have an impact on other elements of survival such as foraging.
2.5 The present study
The aviary used for the current study consisted of three separate species – the budgerigar, the cockatiel and the red-rumped parakeet. A focus on the intra and interspecific interactions was conducted in this study as well as observations of individual behaviour. Further observations relate to aggression and the expression of stereotypies which indicate welfare issues. This study aims to develop an understanding of bird behaviour and the relationship this shares with the captive environment, through studying individual and grouped species behavioural changes after a change of environment. The main objective is to establish present behaviour within the aviary and compare to behaviour once the environment has been adapted through changing perching. Further objectives include recording aggressive interaction frequency during each environment change, recording the number of new locations made per bird under each environment change and to analyse any stereotypies which may or may not be present and then try to counteract these through the environment changes. It is hypothesised that more active locomotive behaviours will be seen where perches are arranged further apart through height as individuals may have to assert their dominance through holding the 'best ' perching position. The null hypothesis is that no behavioural changes will be found during each perch arrangement.
3.0 Methodology
3.1 Subjects
The subjects in this study were all of the Psittacine family of birds – budgerigars (Melopsittacus undulatus), cockatiels (Nymphicus hollandicus) and red-rumped parakeets (Psephotus haematonotus). The group consisted of three opposite-sex pairs of budgerigar, three opposite-sex pairs of cockatiel and one opposite-sex pair of red-rumped parakeets. Of these, two budgerigars were related as were two of the cockatiels, but the others were all non-related.
3.2Enclosure
The birds were kept in a hexagonal, outdoor aviary with an indoor and outdoor area. The outdoor area was the main area used as a nesting female budgerigar prevented other birds from accessing the indoor area during observations. The birds were subject to ambient temperatures and environmental conditions including heavy rain, strong winds and snow. Perching in the aviary consisted of one, long perch which measured the entire width of the aviary and was placed at the bottom of the roof to allow shelter at night. Additional perches were one apple tree branch that allowed for perching nearer to the base of the aviary and one in the outdoor area to allow for bathing in rain and gnawing. Natural lighting was used during observations.
3.3 Feeding
Feeding consisted of commercial aviary bird seed alongside fresh vegetables and fruit which are given daily. Time of feeding generally occurs around 1pm each day and, at this time, the introduction of fresh apple tree branches and twigs took place for gnawing and additional perching in the outdoor area. The feed was accessible to the birds at all times and was only added to during feeding times. Drinking water was also available at all times.
3.4 Perch arrangements
The experiment involved three perch arrangements -control, experiment one (horizontal) and experiment two (vertical). The control consisted of the original set up in the aviary – see section 3.2. The horizontal arrangement was set up to provide perching that was all at the same height. Three perches were installed around 1.5 metres from the ground in the aviary at various angles and positions. The vertical arrangement involved the same three perches being re-arranged to different heights approximately 30-50cm apart in height at various angles and positions. Feed and water locations remained the same to the control and feed was provided at the same time of day. No other changes were made to the aviary or the routine of the birds during observations.
3.5 Data collection
Filming of the control, horizontal and vertical arrangements was completed between 11am and 12.30pm over three days of a week. Three hours of data was collected per set-up. During this time, the birds were subject to any 'normal ' disturbances including wild birds, passing traffic and aeroplane noise. Filming took place outside of the aviary with a non-invasive camera hidden in vegetation. Once films had been collected, the films were analysed and data was recorded at 15 second intervals for each hour of video for each individual. Behaviours recorded included perching, locomotive, preening, social, feeding and sleeping with the addition of nesting behaviour for the single female budgerigar. Also recorded was the number, type and victims of aggressive interactions as well as which individual performed the aggression. Furthermore, the number of new locations – where an individual had moved to a different perch or area – were recorded to analyse activity levels in response to the different perch arrangements.
4.0 Results
Data was entered into Microsoft Excel and Minitab 15 to be analysed. Due to the large amounts of data recorded, results are generalised into groups of behaviour rather than specific behaviours. Tables 1, 2 and 3 contain a summary of the data for the each of the species involved in the experiment. It should be noted at this time that sleeping and nesting behaviour have been combined to allow the nesting female budgerigar to be included in the results – percent of time sleeping for the budgerigars is not actual time spent sleeping, but includes the fact that the female was nesting for a majority of observations.
Table 1. The percent of time the parakeets spent performing each behaviour. The main differences are shown in the vertical arrangement where an increase of almost 8% of time is spent feeding. Type of behaviour | Control | Horizontal | Vertical | Perching | 80.75% | 85.99% | 76.60% | Locomotive | 2.16% | 1.87% | 2.43% | Preening | 8.55% | 3.01% | 4.51% | Social | 0.00% | 0.00% | 0.00% | Feeding | 8.55% | 6.68% | 16.46% | Sleeping and nesting | 0.00% | 0.00% | 0.00% | Mating | 0.00% | 0.00% | 0.00% |
Table 2. The percent of time the cockatiel population spent performing each behaviour type during each arrangement. The main changes are shown in the preening row where a drop of over 10% of time spent performing preening has been expressed in the horizontal and vertical arrangements. Type of behaviour | Control | Horizontal | Vertical | Perching | 67.73% | 64.06% | 56.11% | Locomotive | 2.77% | 2.28% | 4.17% | Preening | 22.76% | 8.69% | 9.54% | Social | 0.37% | 0.00% | 0.14% | Feeding | 2.45% | 14.85% | 8.66% | Sleeping and nesting | 3.70% | 12.70% | 20.56% | Mating | 0.00% | 0.00% | 0.00% |
Table 3. The percentage of time the budgerigars spent performing each behaviour type during observations. Very subtle changes in behaviour are shown, including a slight increase in preening behaviour in both the horizontal and vertical arrangements. Type of behaviour | Control | Horizontal | Vertical | Perching | 63.29% | 62.19% | 61.41% | Locomotive | 5.30% | 4.23% | 4.26% | Preening | 6.90% | 10.34% | 8.70% | Social | 4.87% | 2.50% | 3.10% | Feeding | 4.29% | 6.30% | 6.16% | Sleeping and nesting | 14.40% | 14.25% | 16.18% | Mating | 0.00% | 0.22% | 0.00% |
Data was then put into graphs to show the proportionate amount of time each species displayed each behaviour under each arrangement. Figure 1 shows this for the parakeets, figure 2 for the cockatiels and figure 3 for the budgerigars. The total number of possible behaviours for each arrangement was calculated at 626 for the control, 614 for the horizontal and 720 for the vertical due to technical issues with some recordings. Therefore, percentages are relative to the appropriate total of possible behaviours to maintain reliability of results.
The individuals must now be analysed to see if changes in behaviour occurred between arrangements. The same consideration has been made for the total number of possible behaviours in order to create more accurate results, so percentages are relative to the possible total number of behaviours for each arrangement. To analyse individuals, changes between time spent performing behaviours will be looked at under each arrangement.
Table 4. The percentage of time spent performing each behaviour type by the individual parakeets during each arrangement. Few changes have occurred, except for a slight increase in time spent feeding from both individuals during the vertical experiment. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Parakeet 1 | | | | | | | | C | 79.39% | 2.56% | 8.15% | 0.00% | 9.90% | 0.00% | 0.00% | H | 86.81% | 2.77% | 1.30% | 0.00% | 9.90% | 0.00% | 0.00% | V | 79.17% | 2.50% | 2.50% | 0.00% | 15.83% | 0.00% | 0.00% | Parakeet 2 | | | | | | | | C | 82.11% | 1.76% | 8.95% | 0.00% | 7.19% | 0.00% | 0.00% | H | 85.18% | 0.98% | 4.72% | 0.00% | 8.96% | 0.00% | 0.00% | V | 74.03% | 2.36% | 6.53% | 0.00% | 17.08% | 0.00% | 0.00% |
Table 5. The percentage of time each individual cockatiel spent performing each type of behaviour. It appears that preening, in general, decreased during the horizontal and vertical arrangements and feeding was generally more frequent during the horizontal arrangement. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Cockatiel 1 | | | | | | | | C | 68.37% | 5.43% | 20.93% | 1.28% | 0.96% | 3.04% | 0.00% | H | 69.22% | 2.28% | 5.86% | 0.00% | 19.06% | 3.58% | 0.00% | V | 50.69% | 4.86% | 11.81% | 0.42% | 12.50% | 18.75% | 0.00% | Cockatiel 2 | | | | | | | | C | 67.89% | 3.83% | 24.44% | 0.00% | 1.28% | 1.28% | 0.00% | H | 56.35% | 2.28% | 14.82% | 0.00% | 19.71% | 7.65% | 0.00% | V | 45.69% | 7.78% | 8.89% | 0.00% | 8.33% | 28.47% | 0.00% | Cockatiel 3 | | | | | | | | C | 74.12% | 0.96% | 19.81% | 0.32% | 4.15% | 0.64% | 0.00% | H | 65.96% | 1.63% | 9.93% | 0.00% | 14.33% | 8.14% | 0.00% | V | 60.97% | 3.47% | 8.33% | 0.14% | 4.86% | 18.47% | 0.00% | Cockatiel 4 | | | | | | | | C | 76.20% | 4.95% | 15.18% | 0.32% | 2.88% | 0.48% | 0.00% | H | 77.20% | 3.42% | 7.65% | 0.00% | 12.54% | 13.84% | 0.00% | V | 63.47% | 2.92% | 7.64% | 0.14% | 15.14% | 15.00% | 0.00% | Cockatiel 5 | | | | | | | | C | 74.12% | 0.96% | 19.81% | 0.32% | 4.15% | 0.64% | 0.00% | H | 65.96% | 1.63% | 9.93% | 0.00% | 14.33% | 8.14% | 0.00% | V | 60.97% | 3.47% | 8.33% | 0.14% | 4.86% | 18.47% | 0.00% | Cockatiel 6 | | | | | | | | C | 45.69% | 0.48% | 36.42% | 0.00% | 1.28% | 16.13% | 0.00% | H | 49.67% | 2.44% | 3.91% | 0.00% | 9.12% | 34.85% | 0.00% | V | 54.86% | 2.50% | 12.22% | 0.00% | 6.25% | 24.17% | 0.00% |
Due to the problem of the nesting female budgerigar, an extra column for percentage of time spent nesting is shown in table 6. Obviously this will only be relevant for budgerigar number 6, but it may be the case that time spent nesting or performing other behaviours changed according to the different arrangements. The nesting column for the other five budgerigars will be left blank as it is not relevant for all of the individuals.
Table 6. The percentage of time spent performing each behaviour type by each individual budgerigar. There appear to be no obvious changes in relation to each experiment, except a possible slight increase in preening during horizontal and vertical arrangements. | Perching | Locomotive | Preening | Social | Feeding | Sleeping | Mating | Nesting | Budgerigar 1 | | | | | | | | | C | 82.75% | 8.79% | 4.47% | 0.16% | 3.83% | 0.00% | 0.00% | | H | 78.50% | 7.82% | 7.82% | 0.00% | 6.84% | 2.12% | 0.00% | | V | 82.78% | 7.22% | 7.22% | 0.97% | 5.28% | 0.00% | 0.00% | | Budgerigar 2 | | | | | | | | | C | 74.44% | 8.15% | 6.39% | 3.35% | 5.43% | 0.00% | 0.00% | | H | 82.08% | 6.19% | 5.54% | 1.47% | 4.72% | 0.00% | 0.00% | | V | 77.78% | 6.39% | 5.56% | 4.17% | 5.14% | 0.97% | 0.00% | | Budgerigar 3 | | | | | | | | | C | 66.93% | 2.56% | 12.14% | 11.34% | 3.35% | 0.00% | 0.00% | | H | 66.29% | 2.61% | 16.78% | 6.03% | 7.65% | 0.00% | 0.65% | | V | 72.22% | 4.31% | 13.06% | 4.31% | 5.14% | 1.81% | 0.00% | | Budgerigar 4 | | | | | | | | | C | 73.00% | 6.39% | 9.74% | 2.40% | 6.87% | 1.60% | 0.00% | | H | 58.31% | 3.58% | 21.50% | 0.81% | 11.56% | 4.23% | 0.00% | | V | 61.53% | 4.44% | 13.19% | 3.89% | 9.72% | 5.28% | 0.00% | | Budgerigar 5 | | | | | | | | | C | 73.00% | 4.95% | 7.19% | 11.66% | 3.19% | 0.00% | 0.00% | | H | 66.29% | 4.07% | 9.93% | 6.68% | 3.75% | 0.00% | 0.65% | | V | 72.22% | 2.92% | 11.94% | 4.17% | 5.42% | 7.36% | 0.00% | | Budgerigar 6 | | | | | | | | | C | 9.58% | 0.96% | 1.44% | 0.32% | 3.04% | 0.00% | 0.00% | 84.82% | H | 12.87% | 1.14% | 3.58% | 0.00% | 3.26% | 0.00% | 0.00% | 79.15% | V | 5.97% | 0.28% | 4.72% | 1.11% | 6.25% | 0.00% | 0.00% | 81.67% |
The data from tables 4, 5 and 6 is shown below in graphs which are separated according to each arrangement. Individuals are represented by each column and behaviours are indicated by the separate colours in each column. Nesting only relates to budgerigar 6, for all others, this is sleep.
Further to studying specific behaviours, it was also recorded how often a new location was made by each bird. A new location was defined as an individual physically leaving a perching, sitting or climbing position and re-locating to a completely new area. This may have been changing perches, moving from perch to climbing on the wire or moving from perch to feeding station, as well as other position changes. The results of this data is shown in figures 7, 8 and 9.
Aggressive interactions were also recorded in relation to species performing the aggression during each arrangement. This data is displayed in figure 10.
5.0 Statistical analysis
Statistical analysis was performed in both Microsoft Excel and Minitab 15. Using t-tests, the behaviours were analysed to see individual behavioural changes between arrangements. It was found that cockatiel 1 (p-value = 0.0358) and cockatiel 5 (p-value = 0.0489) showed significantly difference levels of preening behaviour between the horizontal and vertical arrangements. Furthermore, budgerigar 2 displayed significantly different amounts locomotive behaviour between the control and horizontal arrangements (p-value=0.0496). In addition, t-tests were used to assess changes in the species behaviours under each arrangement and it was found that the preening behaviour of the parakeets was significantly different between the horizontal and the vertical arrangements (p-value = 0.0467) and that the feeding behaviour of the budgerigars was also significantly different in the same two arrangements (p-value = 0.0360).
To establish an analysis of the interaction between the individual bird and the perch arrangement, a 2-way ANOVA was used. Each behaviour was assessed and it was found that no statistical difference was found between arrangements, apart from a p-value of 0.056 for social behaviour. The significant difference here was found to be between budgerigars 3 and 5 in relation to the control (p-value = 0.0001 for both individuals). Another 2-way ANOVA was used to indicate an interaction between the different species and their behavioural changes during each perch arrangement. It was found that the only significant statistical difference here was a p-value of 0.058 for feeding behaviour. This difference was found in the behaviour of budgerigar 6 who was nesting at the time so this is not entirely relevant as her behaviour is biased towards her breeding behaviour.
T-tests were used again to indicate any changes in new location frequency between arrangements. It was found that no statistical difference was found between the number of new locations and the arrangement of the perches. Furthermore, no significant difference was found in the aggressive interaction frequency between arrangements, showing that each arrangement had little or no effect on such occurrences.
6.0 Discussion
From the results, it is possible to say that very few significant differences were found in behaviour between each arrangement. However, small differences were seen when looking at the separate species and the individuals even if these were not all statistically significant. Firstly, a slight decrease in preening was expressed (p-value = 0.0469) by the parakeets throughout the experiments (C – 8.55%, H – 3.01%, V – 4.51%) which was also seen in the cockatiels (C – 22.76%, H – 8.69%, V – 9.54%), in particular cockatiels 1 (p-value = 0.0358) and 5 (p-value = 0.0486) between the horizontal and vertical arrangements. Verbeek (1972) found that the annual percentage of time spent preening in magpies was 4.6% in males and 4.2% in females, therefore, it could be said that, during the control, preening behaviours were bordering on stereotypical as some individuals spent between a fifth and a quarter of their time preening. The preening behaviour may have also been influenced by the feeding routine (Savory and Kostal, 1996) whereby birds were anticipating fresh feed being introduced. However, Savory and Kostal (1996) found that preening replaced stereotypical behaviour post-feeding in chickens, indicating that this may not be the reason for higher levels of this behaviour during the present study.
The results may suggest that the control arrangement of the perches was habitual to the birds so other behaviours were limited and boredom was high, whereas during the horizontal and vertical arrangements a newly laid out environment may have been more stimulatory, which has also been suggested by Little and Sommer (2002). However, this was not reflected in all of the results as more active locomotive behaviours remained at a similar level through each arrangement, apart from budgerigar 2. This individual was seen to perform significantly more locomotive behaviour in the control when compared the horizontal arrangement (p-value = 0.0496). This may be because of the horizontal arrangement being all on one level so the bird had to move around a lot more to be able to access food. However, this has only been seen in the one individual so does not relate to the aviary as a whole. Nonetheless, by using the change of environment as a form of enrichment, the present study relates to other previous research such as Bubier (1996). Bubier found that the presence or absence of enrichment directly affected the time budgets of laying hens and that an unenriched environment caused time spent performing particular behaviours to increase, including preening. This suggests that a change in environment provided mental stimulation for the birds in the present study, perhaps decreasing the risk of development of stereotypies and abnormal behaviours.
It was also seen that feeding behaviour increased, although this was not statistically significant, in the parakeets during the vertical (C – 8.55%, H – 6.68%, V- 16.46%) and in the cockatiels during the horizontal (C – 2.45%, H – 14.85%, V – 8.66%),. This may have been due to the feeding stations being closer to certain perches which each species appeared to have a preference to. For example, the cockatiels favoured higher perches, which may have caused the cockatiels to unintentionally be perched closer to a feeding station during the horizontal, therefore making the station more accessible and reducing the costs of feeding. Kacelnik (1984) formed a similar theory as he found that starlings were more likely to travel further to find food if the food was more plentiful as it replenishes the costs of travelling to the food from a central point. This may have been reflected in the aviary as the location of feed stations may have been further away for the cockatiels during the vertical, but closer for the cockatiels during the horizontal. However, as the enclosure in the present study is probably not large enough to allow for travel costs, this may not be relevant. It was also found that there was a significant difference in the feeding behaviour of the budgerigars in the horizontal and vertical arrangements (p-value = 0.0360), indicating a possible similarity between the behaviour of the budgerigars and the behaviour of the cockatiels.
Feeding behaviour of the birds in the aviary differs from studies of natural behaviour as discussed by Magrath and Lill (1985). Compared to the 67% of time spent completing food related activities in Crimson Rosella (Magrath and Lill, 1985), the birds in the present study spent a maximum of 17.08% (parakeet 2 during the vertical arrangement). This suggests that the effect of captive availability of food decreases the need for foraging which would otherwise consume a large amount of time. This has, in turn, given the birds free time in which other behaviours can be expressed. However, this has little relation to the perching arrangement.
Sleeping behaviour in the cockatiels appeared to increase during the horizontal and vertical arrangements (C – 3.70%, H – 12.70%, V – 20.56%). Although this was not statistically significant, it may be an indication that a possible increase in mental stimulation caused an increase in sleeping behaviour for relatively inactive individuals due to an increase in brain activity. Nonetheless, there appears to be limited research in this area including Tagney (1973) who found that an enriched environments caused rats to sleep for longer. This, however, may not be the case as the weather conditions played a factor, particularly in the vertical arrangement where temperatures were below 0ºC and snow was present. It has been discussed by Berger and Phillips (1995) that sleep is beneficial in cold weather as it has thermoregulatory benefits. This may have been the cause of the increased sleeping during the horizontal and vertical arrangements rather than an effect of the arrangements themselves.
Very slight differences were found in the behaviour of the budgerigars throughout each arrangement. The budgerigars were found to be the most social and performed the widest variety of behaviours including regular allopreening, beaking and mating. This diverse repertoire of behaviours perhaps may be the reason the changes in perch arrangement did not significantly affect the budgerigar behaviour as they were already very active and diverse within the environment. However, it is possible that a slight increase in preening behaviour found in budgerigars 1 (C- 4.47%, H – 7.82%, V – 7.22%) and 4 (C – 9.74%, H – 21.50%, V – 13.19%) during the horizontal and vertical was caused by the new arrangements. There may have been a decrease in social behaviour also by budgerigars 3 (C- 11.34%, H – 6.03%, V – 4.31%) and 5 (C – 11.66%, H – 6.68%, V – 4.17%). These individuals had a pair bond which has been previously discussed as beneficial for breeding purposes and survival (Beaulieu et al., 2009). However, the social interactions of the pair where the female was presently nesting, budgerigars 1 (male) and 6 (nesting female), were less frequent than pairs who were not currently breeding. Although it is obvious that most time and energy of the breeding female was spent nesting in all three arrangements, during the vertical arrangement a slight increase in social activity occurred between the breeding pair (male social activity C – 0.16%, H – 0.00%, V – 0.97%, female social activity C – 0.32%, H – 0.00%, V – 1.11%). However, this is such a slight difference and cannot be said to be significant.
The frequency of aggressive interactions during each arrangement, as seen in figure 10, decreased from the control to the horizontal and vertical. Little and Sommer (2002) found similar results in Langur monkeys where a new environment caused a decrease in aggressive interactions due to increased opportunity for dispersal due to a larger environment. This is a positive change within the social arrangement of the aviary as it could be said that welfare and social stability have been improved. This may be due to the environment being more stimulatory or that there is a larger number of options of perching location so that victims can escape the aggressors. Cornetto et al. (2001) found a similar change when walls were introduced to chicken enclosures. When the enclosure was separated by walls, aggression decreased as the environment provided more areas for individuals to distance themselves from aggressors, and when no cover was provided aggression increased. Thus it could be said that by increasing the complexity of the environment, the frequency of aggressive interactions may decrease.
Limitations of the present study include a disproportionate number of individuals representing each species, as only two parakeets were used in this compared to six cockatiels and budgerigars. This means that more data was available for two species and only a small amount for one species, making comparisons and changes less reliable. However, due to a lack of resources this was a problem which was difficult to overcome. A main limitation was budgerigar 6 nesting during observations. This may have triggered unusual behaviours in the social group as tensions and conflicts may have been raised, so results may be biased for this reason. Furthermore severe weather conditions could have caused biased behaviours, such as an increase in sleeping. Freezing temperatures and heavy snowfall could have contributed to this, particularly in the vertical arrangement as during the control the weather was still cold but it was sunny. Additionally, a lack of comparison with other aviaries could have caused results and conclusions that are only relevant to the aviary in the present study rather than information that can be utilised by bird owners. However, there is plenty of research that supports the theory that changing the environment can improve the behaviour and welfare of captive animals.
For future research, this study could be performed on several different aviaries and results compared to see if general changes are found in multiple enclosures rather than just the one. Furthermore, this could be utilised to assess different species reaction to changing perch arrangements, particularly in relation to dominance. The study by McGowen et al. (2006) could be recreated in domestic species like the cockatiel to see whether a relationship between dominance and choice of perch is seen. This could then be related to aggressive interactions, to see if taking away or adding a particular perching location affects the levels of aggression. This would be beneficial for welfare and would enable a deeper understanding of the mechanisms involved in captive species in order to make husbandry easier.
In conclusion, the results of this study indicate that there may be a relationship between perch arrangement and behaviour in a mixed-species aviary. Although differences are not all significant, it could be said that with more research and further studies into different species, the arrangement of perches could be utilised to discourage individuals who may be performing repetitive stereotypical behaviours as well as generally improve the welfare of caged psittacid species by promoting a wider variety of behaviours and to provide mental stimulation for birds that may otherwise perform boredom behaviours.
7.0 References
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8.0 Appendices
Appendix 1
Summary of email communication between student and project leader (Mark Orminston) regarding data collection – 11/10/2012
Have you heard of time budgets and ethograms? If not look them up in google (search: time budget animal behaviour). This might be the best approach.So it would be like what you have suggested, but you would do a count every 10 seconds or so to see which bird is where. This would give you a % of time spent on each perch for each bird involved over the total study period (30 mins?) - so it is important to know how much time the birds did not spend on the perches as well as how much time they did. Then you would replicate this to get a more accurate time budget. Be sure that you can identify individuals.Try to find examples of other people doing similar research to help you with ideas.
Appendix 2
Summary of email communication between student and lecturer (Kayleigh Liddell) regarding literature review – 8/11/2012
Appendix 3
Summary of email communication between student and Mark Orminston regarding data collection – 18/12/2012
Its a good start. You would need to create an ethogram, which is a table defining each behaviour in detail - for example, exactly what is 'resting '. Should you be noting the position of the bird with respect to the perches too?My concern is how you will collect continuous data for each bird (i.e. counting each behaviour) without spending 100 's of hours watching video footage. I don 't think its possible. So what I would suggest is that you use interval sampling, so you take a visual snapshot of what each bird is doing every 30 seconds. But before going forwards with this idea we need to establish a couple things:1) how many aggressors are there? Are they all squabbling or is it just one or two? Potentially you could do continuous sampling, if you are just looking at 2-3 birds2) how frequent is the aggressive behaviour? If it is as seldom as once every 5 minutes we could miss all the aggressive behaviours if we are doing interval sampling.
The problem with taking a photo every 30 seconds, is that its one still image, and you cannot infer all behaviours from that image. I think the solution is for you to download VLC media player (its free). This is an excellent piece of software that will let you watch your videos frame by frame (or in slow motion). No need to watch the whole video, I would click on every 30 second interval one at a time, and just check a few frames either side of that interval frame to double check what each bird is doing. Ideally you would track each budgie, but if not, just record what each one is doing (number them 1-8 each time, it doesn 't matter if they don 't keep the same number) and at the end we will take an average of what they were doing. We wont be able to say, for example, Budgie number 5 was less aggressive after the change of perch height, but we will be able to say, for example, budgies showed less aggression and more preening behaviour, but similar amounts of resting behaviour on average in response to the new perch configuration.Does this sound like a good plan? If you need a better camera, you might be able to burrow one from college.