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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

THE FUNCTION OF FINE-SCALE SIGNAL TIMING STRATEGIES: SYNCHRONIZED CALLING IN STREAM BREEDING TREE FROGS

Henry D Legett (8803115) 06 May 2020 (has links)
In dense mating aggregations, such as insect and anuran choruses, signals produced at the same time can overlap and interfere with one another, reducing the ability of receivers to discriminate between individual signals. Thus, evolution by sexual selection is expected to result in mating signal timing strategies that avoid overlap. Patterns of signal alternation between competing males are commonly observed in leks and choruses across taxa. In some species, however, signalers instead deliberately overlap, or ‘synchronize’, their mating signals with neighboring conspecifics. Given the assumed high cost of reduced mate attraction when signals overlap, mating signal synchronization has remained an evolutionary puzzle. Synchronization may be beneficial, however, if overlapping signals reduce the attraction of nontarget receivers (predator avoidance hypothesis). Synchronized signals could also constructively interfere, increasing female attraction to the mating aggregation (the beacon effect hypothesis). I investigate these functions of synchronized signaling in two species of tree frogs that synchronize their mating calls: the pug-nosed tree frog (<i>Smilisca sila</i>) and the Ryukyu Kajika frog (<i>Buergeria japonica</i>). To examine the trade-offs imposed by call synchronization in each species, I conduct a series of field and laboratory playback experiments on target (female frogs) and nontarget (eavesdropping predators) receivers of frog calls. Results from these experiments support both hypotheses, suggesting that synchronized frog calls can reduce the attraction of predators and attract mates to the chorus. In addition, I found reduced preferences for fine-scale call timings in female <i>S. sila</i> and <i>B. japonica</i>, deviating from the expected preferences observed in many other anuran and non-anuran species. Thus, while males may enjoy multiple benefits from synchronized mating signals, relaxed sexual selection for non-synchronous signals may be key to the evolution and maintenance of mating signal synchrony.
82

Into the Comfort Zone: Understanding Swine Thermal Preference

Lindsey A Robbins (10071391) 01 March 2021 (has links)
Exposure to thermal stress can negatively impact an animals' overall welfare, resulting in decreased body condition, lower reproductive success, and in severe cases, mortality. The swine industry has prioritized efficient production and as a result has gained rapid improvements in lean growth and increase litter sizes. Unfortunately, modern swine are unable to cope with the negative effects of heat stress. Thus, it is crucial to understand the preferred temperature of swine to create recommendations on when to initiate mitigation strategies to combat the negative effects of thermal stress. However, several different factors contribute to an animals' thermal comfort and thermal preference will differ based on age, reproductive stage, social context, early life thermal stress, and behavior. Thus, making it exceptionally difficult to classify an animal's thermal comfort zone. These studies aim to highlight how those factors influence thermal comfort in pigs and help guide recommendation polices for housing pigs in their preferred temperatures.<br>
83

Is there hope beyond fear? Effects of social rehabilitation on unsocialized stray dogs

Casaca, Miriam January 2021 (has links)
Unsocialized stray dogs live unrestrained in urban areas, having limited to no direct contact with humans. Aggressive behaviour towards humans leads to their apprehension to shelters, where they tend to stay permanently. This study aimed to determine if unsocialized stray dogs could be rehabilitated and develop the social skills needed for adoption. Six unsocialized stray dogs (Group Stray) and 12 socialized dogs (C1: Control Group 1, n=6; C2: Control Group 2, n=6) housed in a shelter were selected. Stray and C2 dogs went through two training phases: social rehabilitation towards humans and leash training. Sociability towards humans and behaviour on a leash were tested in all groups following Valsecchi et al. (2011). Sociability Tests (ST) and Leash Tests (LT) were conducted before any intervention (ST1), after sociability training (ST2, LT1) and after leash training (ST3, LT2). Training sessions and tests were video recorded and posteriorly analysed by four observers. Results showed that for Stray, but not for C1 and C2, there was a significant increase in sociability from ST1 to ST3. Moreover, for Stray Group there was a significant decrease in the frequency of fear-related behaviours between ST1 and ST3. For leash behaviour, no significant changes were found from LT1 to LT2 for neither group. However, there was considerable individual variation, as not all strays overcame their extreme fear towards humans. These findings suggest that dog­–human interactions can be improved through training for dogs who do not show extreme fear and/or aggression towards humans.
84

Context dependent variation in aggression and mating behaviour in the pygmy halfbeak (Dermogenys collettei) : a study of wild population

Michalak, Piotr January 2021 (has links)
To understand animal behaviour, it is important to consider the environment in which it occurs. The environment, consisting of both abiotic factors and social context, is usually highly variable and leads to variation in individual’s and group’s behaviour. To better understand the environmental influences on behaviour of pygmy halfbeaks (Dermogenys collettei), a small live-bearing fish, I viewed videos of shoals of wild halfbeaks in Singapore. I investigated effects of environmental variation (water depth, canopy cover and water vegetation) and social environment (group size and male to female sex ratio) on halfbeaks’ aggression and mating behaviours. I found that environment had little effect and most variation between studied shoals was probably due to social factors. I found some evidence for aggression increase in larger shoals, primarily in males. Sex ratio had different relation with aggression for individual sexes and mating behaviours decreased when sex ratio became more male biased. This study shows that halfbeaks probably modify their behaviour in relation to social environment. I also show that these changes are similar to those described in other species, which strengthens the validity of using halfbeaks to study social interactions.
85

Injurious pecking behavior of Pekin ducks on commercial farms: characteristics, development and duck welfare

Yiru Dong (8086220) 05 December 2019 (has links)
<p></p><p>Injurious pecking is one of the major welfare concerns for poultry and other captive birds. Injurious pecking behavior can result in welfare problems including feather and skin damage, pain, substantial heat loss because of feather loss, and even death of the recipient bird. Injurious pecking can also cause economic losses because of reduced production efficiency, increased mortality and reduced feed conversion ratio. Injurious pecking behavior includes feather pecking, feather picking, cannibalism and aggressive pecking. Feather pecking, when a bird uses its beak or bill to peck at the feathers of another bird, can be categorized as either gentle feather pecking (repeated and light pecks) or severe feather pecking (singular and hard pecks). Feather picking is described as a self-damaging behavior that occurs in psittacine species such as parrots and also in ducks. Cannibalism is classified as either tissue pecking (persistently forceful pecks directed at exposed skin) or vent pecking (pecks directed at the top of cloaca or below the cloaca). Unlike feather pecking, feather picking and cannibalism, which are not associated with aggression, aggressive pecking establishes and maintains the dominance hierarchy. Limited studies have examined injurious pecking of Pekin ducks, but results from previous research examining duck picking behavior and feather quality suggested that ducks pick mostly at themselves and that the development of picking is related to feather growth and worsens with age. Scant information is available regarding the prevalence of injurious pecking behavior and characteristics of the behavior. </p> <p> </p> <p>To address some of the gaps in the knowledge regarding injurious pecking behavior of ducks, this study examined 1) age-related changes in frequencies and durations of preening behavior and injurious pecking behavior of Pekin ducks, including self-picking and feather pecking; 2) the body locations most frequently affected, and whether feather removal and feather eating occurred concurrently with injurious pecking; 3) the prevalence of injurious pecking behavior; and 4) age-related changes in duck welfare that may be associated with injurious pecking. Information about preening behavior was recorded because injurious pecking and preening behavior may have similar age-related patterns, as previous studies have suggested that increased levels of preening behavior are related to feather growth.</p> <p>Data were collected on 5 commercial duck flocks on 5 farms. Welfare data were collected from all 5 flocks and behavior data were collected from 2 of the 5 flocks. For the two flocks, duck behavior was video-recorded over two consecutive days at 20-22d (Period 1), 27-29 d (Period 2), and 34-36 d (Period 3). Scan sampling and focal animal sampling were used to analyze the video recordings and determine the frequencies and durations of injurious pecking behavior (gentle feather pecking, severe feather pecking, self-picking and aggressive pecking). For scan sampling, the percentage of ducks performing injurious pecking behavior were recorded every 30 min from 0900h to 1500h. For both scan and focal animal sampling, the viewing area of each camera installed in the barn was divided into eight equal squares (observation areas), of which four were randomly selected for analysis. For focal animal sampling, one duck was randomly selected from each observation area and observed for 30 min from 0945h to 1015h and 1345h to 1415h ((n=8 ducks per camera (4 ducks in the morning and 4 ducks in the afternoon) and n=24 ducks per barn)) to determine the duration and frequency of injurious pecking behavior and preening behavior. For all five flocks, duck welfare (feather quality, feather cleanliness, nostril cleanliness, eye condition, footpad condition and gait) was assessed in 100 ducks from each flock between 17-18 d (Period 1), 29-30 d (Period 2), and 36-37 d (Period 3). Welfare data and frequencies of behaviors from focal animal sampling were analyzed using the GLIMMIX procedure (SAS 9.4). Scan animal sampling data and behavioral durations from focal animal sampling data were analyzed using the MIXED procedure (SAS 9.4). </p> <p> </p> <p>The most frequently observed form of injurious pecking behavior was gentle feather pecking, which increased from Period 1 to Period 2 (P < 0.001), then declined from Period 2 to Period 3 (P < 0.001). Gentle feather pecking was most frequently directed at the tail, wings and back. Removal of feathers was observed 13 times, and feathers were eaten 7 times in the 6 days of video observation. Ducks’ eye condition, feather cleanliness under the tail, and feather quality on all the assessed body locations, except for the neck, worsened with age. Age was a major factor affecting the development of injurious pecking behavior including the proportion of ducks performing gentle feather pecking behavior (P < 0.001), frequency and duration of gentle feather pecking behavior (frequency: P < 0.001; duration: P < 0.001), and other injurious pecking behavior (frequency: P = 0.038; duration: P = 0.036). From scan sampling, 1.85% of the ducks were observed performing severe feather pecking behavior, 6.84% of the ducks were observed performing aggressive pecking behavior, and no duck was observed performing self-picking behavior in the total of 1082 ducks performing injurious pecking behavior across the 3 periods. From focal sampling, 83.33% of the ducks were observed performing gentle feather pecking behavior, 13.89% of the ducks were observed performing severe feather pecking behavior, 16.67% of the ducks were observed performing aggressive pecking behavior, and only 1.39% of the ducks were observed performing self-picking behavior of the total of 288 ducks observed. Frequency and duration of preening behavior increased from Period 1 to Period 2 (frequency: P = 0.004; duration: P < 0.001), then declined from Period 2 to Period 3 (frequency: P < 0.001; duration: P < 0.001). </p> <p> </p> <p>In conclusion, feather pecking between conspecifics was the most frequently performed pecking behavior of commercial Pekin ducks. Age was a major factor affecting the development of pecking behavior, which peaked at 27-29 d. The body locations that injurious pecking behaviors were most frequently directed at were the tail, wings and back, consistent with the welfare condition results that indicated a worsening tail, wing and back feather quality with age. Feather removal and feather eating were infrequently observed, which might indicate that injurious pecking behavior in Pekin ducks is not for the purpose of pulling out and eating the feathers. The frequency and duration of gentle feather pecking and preening behavior followed a similar pattern with age; however, further research is needed to evaluate whether these behaviors are associated. This study provided more details about age-related changes in injurious pecking behavior and welfare of commercial Pekin ducks. However, further work is needed to investigate specific causes of and methods to reduce injurious pecking behavior of Pekin ducks.</p> <p> </p><br><p></p>
86

Novel methods for assessing and mitigating handling stress in sea turtles

Sophie K Mills (12469548) 27 April 2022 (has links)
<p>Green turtles (<em>Chelonia mydas</em>) perform ocean-crossing migrations, maintain healthy marine ecosystems, generate income through tourism, and are endangered and declining globally. For these reasons, among others, this species has been a focus of numerous research programs worldwide for almost a century. Most of these sea turtle research programs require some form of animal handling to collect the required data (e.g., tagging information or the collection of biological samples). However, this can cause stress, especially for wild animals, and that raises ethical issues. Here, I describe novel methods for assessing and mitigating the effects of handling stress on green turtles. Specifically: (1) I used a combination of animal-borne cameras and drone footage to determine how handling stress altered the post-release behavior of green turtles and (2) I used a photo-ID software to determine whether flipper scales can provide more accurate identifications than the more conventionally used facial scale patterns. </p> <p><br></p> <p>I found that turtles spent more time swimming and had shortened dive intervals in the first 30 mins after capture and attachment of a camera than in the hours that follow. Instances of socializing, foraging and resting increased over the 3-3.5 h after release. Animals recorded by drone and not captured were less likely to rest, which suggests this behavior may be a recovery response to handling and/or stress. The same animals were also more likely to socialize. When determining the accuracy of flipper or facial images for photo-ID, I found that head scales provided correct identifications 80% of the time, whereas the flipper provided correct identifications 100% of the time. This implies that researchers could use the flipper instead of more invasive tagging techniques, such as metal flipper tags or using lights to photograph the face for photo-ID, which can induce stress.</p>
87

Attachment Style and Social Fear in Dogs from Commercial Breeding Kennels

Allegra Kathryn Stahl (16647627) 26 July 2023 (has links)
<p>Much of the demand for purebred dogs in the USA is met by commercial breeding kennels (CBKs). In CBKs, adult dogs have been reported to exhibit signs of fear towards strangers. Social fear is a particular welfare concern as it may lead to acute and chronic stress in the kennel, and later, after dogs are retired and rehomed. Studies on pet and shelter dogs have shown that the type of attachment style dogs have with their caretakers is associated with their social behavior towards strangers. Thus, the aims of this study were to characterize the attachment styles of dogs from CBKs to their caretakers, and investigate relationships between the types of attachment styles observed and social fear behaviors in this population of dogs. Forty-eight adult dogs were tested from three CBKs in Indiana, USA. Each dog was subjected to a standard battery of tests, including a Secure Base test to classify attachment styles, a Stranger Arena test to measure the duration and frequency of key social behaviors toward a stranger, and a Paired-Effect test to measure the duration and frequency of social behaviors towards a stranger in the presence of a caretaker. Twenty (41.67%) dogs were classified as secure, 16 (33.33%) as insecure ambivalent, 9 (18.75%) as insecure avoidant, and 3 (6.25%) as insecure disorganized. ANOVA tests showed that secure and ambivalent dogs approached the stranger more frequently (F2,45 = 11.865, <em>p </em>< 0.001), spent more time in close proximity (F2,45 = 15.968, <em>p </em>< 0.001), and solicited contact more frequently (F2,45 = 4.58, <em>p </em>= 0.023) from them than did avoidant dogs. Wilcoxon Signed-Rank Tests showed that secure, ambivalent, and avoidant dogs all initially approached the stranger more quickly in the paired-effect test than in the stranger arena test (<em>p </em>< 0.05). Secure and ambivalent dogs also spent more time in proximity to (<em>p </em>< 0.001) and solicited more contact from (<em>p </em>< 0.01) the stranger in the paired-effect test than in the stranger arena test. These results suggest that there is an association between type of attachment style and fear behaviors towards a stranger in this sample of dogs. Understanding connections between attachment style and social fear, and their implications for stress and welfare in dogs from CBKs may help inform breeders’ selection criteria and breeding decisions. It may also inform breeders’ socialization, social interactions, and related management practices, which in turn may help to reduce dogs’ social fear and enhance their long- term welfare outcomes in the kennel. This understanding may also aid rehoming efforts. With this increased understanding, breeders could inform new owners about behaviors they can expect from their dogs which may help avoid a potential mismatch in expectations. This in turn may help keep dogs in their homes and improve their welfare in the long-term. </p>
88

EFFECTS OF ENVIRONMENTAL ENRICHMENT ON TURKEY BEHAVIOR, WELFARE AND WALKING ABILITY

Yiru Dong (8086220) 16 December 2022 (has links)
<p>    Injurious pecking, aggression, footpad dermatitis and leg abnormalities have been identified as major welfare issues in commercial turkey production, which lead to culling and mortality, downgraded carcass value and economic losses due to decreased productivity and carcass damage. Injurious pecking includes aggressive pecking (head pecking), feather pecking, and cannibalism. Aggressive pecking is related to aggression and is more prevalent in males than females. Feather pecking consists of non-damaging gentle feather pecking and severe feather pecking that can cause feather, skin and tissue damage, and even death in extreme cases. Common methods to control injurious pecking include infrared beak treatment and reduced light intensity, but those methods can result in inconsistent effects on feather condition and negative affect eye development. Footpad dermatitis and leg abnormalities can lead to lameness and an inability of turkeys to access feed and water. </p> <p>    Environmental enrichment, which is the modification of the environment of captive animals to improve their biological functioning, is one alternative way of reducing injurious pecking and potentially improving turkeys’ walking ability. In meat-type poultry production, five types of environmental enrichment are usually used, which include social enrichment, occupational enrichment, physical enrichment, sensory enrichment and nutritional enrichment. For turkeys, some types of physical enrichment such as foraging and pecking enrichment have been found to be most effective in reducing injuries caused by injurious pecking and elevated structures (e.g. platform or straw bale) were effective in promoting locomotive exercise. </p> <p>    To address some of the gaps in the knowledge regarding the effects of environmental enrichment on turkey behavior, welfare and walking ability, this study examined 1) age-related changes in welfare and gait when turkeys are provided with different types of environmental enrichment; 2) the effects of different types of environmental enrichment on enrichment usage and injurious pecking behavior; 3) specific behaviors and relative location of turkeys when they interact with different types of environmental enrichment.</p> <p>    Data were collected from a total of 420 beak-trimmed tom turkeys housed in 24 littered pens located in two rooms within the same barn. Birds were randomly assigned to six treatment groups with 4 replicate pens per treatment group, including five enrichment groups (straw bale, platform, platform + straw bale, pecking block and tunnel) and a control group (no additional enrichment provided). Welfare measures (wounds on the head, neck, snood, back and tail; beak abnormalities; feather quality; feather cleanliness; and footpad condition) and walking ability (gait) were assessed at 8, 12, 16 and 19 wk. Postmortem footpad condition was assessed at 19 wk. Behavior of turkeys was video recorded at 8, 12 and 16 wk and analyzed using scan sampling. The proportions of turkeys performing target behaviors were determined every 15 min (07:00 h - 22:00 h). Welfare and gait data were analyzed using PROC LOGISTIC with Firth bias-correction. Behavior data were analyzed using PROC GLIMMIX.</p> <p>    Better wing feather quality with age was observed in turkeys in the straw bale and tunnel groups. Footpad condition worsened with age for turkeys in all treatment groups except for the straw bale group. Gait worsened with age in all treatment groups while earlier onset of gait problem was observed in turkeys provided with a tunnel or no enrichment (control group). The average proportion of turkeys using the enrichments declined with age. Turkeys provided with a platform + straw bale had the highest levels of enrichment usage, followed by the platform group. Preening and severe feather pecking behavior did not change with age and were unaffected by the type of enrichment provided. Aggressive pecking and gentle feather pecking were not influenced by the type of enrichment provided. Higher average proportions of turkeys were observed performing environmental pecking in the control group than in the platform + straw bale group. Turkeys’ usage of enrichments mainly included resting on top, locomotion, pecking and remaining under the enrichment when they had access to platforms; resting on top, locomotion and pecking when they had access to straw bales or pecking blocks; and remaining in the tunnel and pecking when they had access to a tunnel.</p> <p>    In conclusion, environmental enrichment showed beneficial effects on turkey wing feather quality, footpad condition and walking ability. Providing tom turkeys with straw bales and tunnels as environmental enrichment can help improve wing feather quality with age and providing straw bales may reduce the development of footpad dermatitis under suboptimal litter conditions. Providing enrichments that can help increase turkey activity and locomotion, including enrichment that can satisfy turkeys’ pecking and foraging needs (straw bale or pecking block) and elevated structures (bale or platform), may be beneficial for turkey walking ability. Multi-functional environmental enrichments, especially a combination of enrichment objects, can promote turkeys’ natural behaviors. Turkeys had the highest enrichment usage when provided with a combination of different enrichment objects (e.g., platform + straw bale) that can serve multiple functions to fulfill their different behavioral needs. Providing a platform only can also achieve high enrichment usage. Turkeys gradually lost interest in interacting with enrichments over time, which may be associated with habituation, destruction of some enrichment objects (e.g. straw bale and pecking block) and fecal contamination on the surface of enrichments. </p> <p>    Future research will be valuable in examining the effects of different types of environmental enrichment in various commercial facilities and across different flocks and seasons. Research is needed to examine the effect of enrichments on turkey activity levels and whether there is a relationship between increased activity level and turkey walking ability. In addition, the effectiveness of making periodic changes to the enrichment objects and using unpredicted schedules of presenting the enrichments on habituation will need to be examined.</p>
89

<b>Untapped Potential: Systematics and Evolution of the African Toktokkie Beetle (Tenebrionidae: Sepidiini)</b>

Olivia Mcmurry Gearner (17584170) 11 December 2023 (has links)
<p dir="ltr">Sepidiini is a large and morphologically diverse tribe of darkling beetles (Tenebrionidae) in the subfamily Pimeliinae, containing ~1,000 species and subspecies. Despite the presence of many large and charismatic species and the cultural significance of some of its members, the toktokkie beetles, this tribe has been lacking revision at all taxonomic levels. To develop a framework for taxonomic revisionary work, in Chapter 1, I reconstructed a phylogeny of the tribe using targeted enrichment sequencing data. I also scored a comprehensive suite of diagnostic characters for the tribe to test in a phylogenetic context. Based on the results of the study, I proposed revising the subtribe Oxurina Koch, 1955, <b>sens. nov. </b>(now containing the genera <i>Oxura </i>Kirby, 1918, and <i>Miripronotum </i>Louw, 1979) and moving the genera <i>Decoriplus </i>Louw, 1979, <i>Pterostichula </i>Koch, 1952, <i>Stenethmus </i>Gebien, 1937b, and <i>Synhimba </i>Koch, 1952 to a new subtribe Stenethina <b>subtr. nov. </b>The tree topology also supports revising or synonymizing the genera <i>Dichtha </i>Haag Rutenberg, 1871, and <i>Amiantus </i>Fåhraeus, 1870,<i> </i>and revising the genus <i>Somaticus </i>Hope, 1840.</p><p dir="ltr">In Chapter 2, I performed a partial revision of the subtribe Hypomelina Koch 1955. A new genus <i>Bufoniopsis </i><b>gen. nov. </b>is erected containing one newly described species <i>Bufoniopsis hypnosis</i> <b>sp. nov. </b>The genus <i>Hypomelus </i>Solier, 1843, and all of its species are redescribed, and three new species are described: <i>Hypomelus johnprinei</i> <b>sp. nov</b>., <i>Hypomelus lorettalynnae</i> <b>sp. nov.</b>, and <i>Hypomelus tomhalli</i> <b>sp. nov</b>. One species was moved from <i>Hypomelus </i>to <i>Triangulipenna</i><i> </i>Louw 1979<i> </i>and redescribed, <i>Triangulipenna vulipnus </i>(Haag Rutenberg, 1873)<i> </i><b>comb. nov. </b><i>Triangulipenna </i>was redescribed and three new species were described, <i>Triangulipenna tylerchildersi </i><b>sp. nov.</b>, <i>Triangulipenna dollypartonae</i> <b>sp. nov</b>., and <i>Triangulipenna ralphstanleyi</i> <b>sp. nov</b>. A revised key to the genera of Hypomelina is provided as well as keys to the species of <i>Hypomelus </i>and <i>Triangulipenna</i>.</p><p dir="ltr">Toktokkie beetles—members of the subtribe Molurina Solier, 1843—are known for their substrate tapping behavior which is a form of sexual communication in which beetles tap their abdomens on the ground to locate mates. Despite the fact that this behavior is well-known among people in southern Africa, very little research has been done on the topic. In Chapter 3, I document variation in tapping patterns across the subtribe Molurina. Three characters of tap trains were found to vary: length of tap trains, tapping rate, and tapping pattern. Ancestral state reconstruction was performed for each of the characters. Characters were found to be only partially linked to ancestry. Additionally, in any given locality sampled, no two species had the same “song”. This suggests that signal partitioning could be influencing species “songs”.</p>
90

Patterns of parental care and chick recognition in a joint-nesting rail, Pūkeko (Porphyrio melanotus melanotus)

Young, Courtney A January 2017 (has links)
Group living is a widespread social system among animals. Within these groups, decisions on interactions between individuals can be facilitated through knowledge about individual identity and kinship. Individual identity allows for the recognition of individuals from past interactions and thus, information on likelihood of reciprocity and group-membership can be gained. The benefit for cooperative interactions, specifically, increases with the level of relatedness between the helper and the recipient. Thus, knowing who is kin, is an essential ability among group-living species and remembering individual identity helps to maintain long-term relationships and inform future decisions. Kin recognition can be facilitated through temporal and spatial overlap (i.e. familiarity) or through phenotypic-templates (i.e. phenotype matching). The goal of this thesis was to explore recognition in the joint-nesting pūkeko (Porphyrio melanotus melanotus). For the first portion of this thesis (Chapter II), I tested for evidence of phenotype matching in pūkeko using a cross-fostering experiment. Comparing survival and growth between fostered and non-fostered offspring, I provide evidence that pūkeko do not use phenotype matching as their mechanism for kin recognition. In Chapter III, I show that pūkeko chick distress calls may have an individual and group signature. I found variation in the vocal parameters between individual chicks and social groups. I also tested for response of adults towards chick distress calls of their own group. Using a playback-choice experiment, I report a biased response of adult pūkeko towards the distress call of their own group's chicks rather than the call of a distressed chick from a foreign chick. / Thesis / Master of Science (MSc) / Kin recognition is an essential ability for social species. Knowing whom is kin can help inform decisions on cooperation and conflict. I explored whether the joint-nesting pūkeko use familiarity or phenotype matching to recognise cross-fostered offspring. I experimented to determine if adult pūkeko can recognise the distress vocalizations of chicks in their group. I found no evidence that pūkeko use phenotypic templates to recognise cross-fostered chicks as non-kin. However, adult pūkeko showed a bias in response towards the distress calls of their own versus unfamiliar chicks. Individual chick distress calls, while variable from day-to-day, show group-specific similarities.

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