Browsing by Author "O'Riain, Justin"

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    Anti-predator behaviour of Cape fur seals Arctocephalus pusillus pusillus in relation to predation by white sharks Carcharodon carcharias around Seal Island, False Bay, South Africa
    (2010) De Vos, Alta; O'Riain, Justin
    How predators affect the behaviour of their prey is one of the most studied subjects in behavioural ecology, with many hypothesis and models explaining how animals should behave and even more descriptive studies detailing how they do. The unification of the empirical with the theoretical, however, remains limited. The overall aim of my thesis was to address this paucity at Seal Island, South Africa, where recently quantified patterns of predation pressure by white sharks Carcharodon carcharias on Cape fur seals Arctocephalus pusillus pusillus suggested a landscape of fear particularly apposite to this.
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    Behavioural ecology of white sharks carcharodon carcharias in False Bay, South Africa: towards improved management and conservation of a threatened apex predator
    (2014) Kock, Alison Ann; O'Riain, Justin; Griffiths, Charles L; Mauff, Katya
    The coastal waters off South Africa support a significant proportion of the global white shark population, with at least four well-established coastal aggregation sites. How critical these sites are to the southern African and hence global white shark population depends to a large extent, on their levels of residency a nd site fidelity, in relation to potential threats. Here, I attempt to provide such data by studying the annual and seasonal presence of white sharks in False Bay. From 1 April 2004 - 31 December 2007, a total of 68 (46 female, 22 male) sharks, ranging in length from 1.7 to 5 m, were tagged with acoustic transmitters and monitored on an array of 30 receivers, distributed along the Inshore region of False Bay and at Seal Island, for a maximum of 1349 days. I used generalized linear mixed effects models to investigate the effects of season, habitat type, sex, size and time of day on shark presence. Most tagged sharks were immature animals, some of which were detected in the Bay in all months and across all years. In autumn and winter, males and females aggregated around Seal Island, where they fed predominantly on young-of-the-year seals. Sharks, regardless of sex or size, over-dispersed on the South side of the Island at sunrise, where the probability of encountering predator-naïve seals was highest. Shark presence at Seal Island mirrored the spatial distribution of predation around the Island, which was highest on the South side within 400 m of the Island, and at sunrise. In spring and summer, there was marked sexual segregation in presence, with females frequenting the Inshore areas and males seldom being detected in the Bay . Within the Inshore region, female white sharks showed a preference for beach, compared to rocky, mixed and harbour habitats. The preference for beach habitat likely reflects a combination of high prey availability, in addition to an open habitat suitable for detecting and securing prey. Overall, the results confirm False Bay as a critical area for white shark conservation as both sexes, across a range of sizes, show high levels of fidelity to the Bay.
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    Cape Town's cats: reassessing predation through kitty-cams
    (2014) Morling, Frances; Simmons, Robert E; O'Riain, Justin
    Domestic cats (Felis catus) are abundant generalist predators that exploit a wide range of prey within and adjacent to the urban matrix. Cats are known to have contributed to the extinction and endangerment (mostly on islands) of a number of indigenous species, including birds, small mammals, reptiles and amphibians. Most research on this important topic has been carried out in the developed world, predominantly in Australia, New Zealand, the U.K., the U.S. and Canada with only four studies carried out in Africa. Of these, two studies in Cape Town suggest that domestic cats have a big impact on wildlife but these studies may have underestimated predation because they failed to account for the proportion of prey not returned to participants’ homes. In this study I used kitty-cams in an attempt to provide a prey correction factor for urban cats in Cape Town, South Africa. I investigated hunting of wildlife by free-ranging domestic cats in Newlands, a suburb of Cape Town, South Africa over 5 weeks in 2013. I monitored 13 cats (6 deep-urban and 7 urban-edge) by questionnaire survey, asking cat owners to record all prey items returned by their cats. A total of 43 prey items were returned, 42% of which were small mammals, 30% invertebrates, 12% reptiles, 9% amphibians and 7% birds. Combining these data with two similar survey studies carried out in Cape Town I estimated that a total of 118 cats caught an average of 0.04 prey items per cat per day. Ten of the 13 cats were also monitored for 3 weeks using kitty-cam video cameras. Participating cats wore a video camera and all activity was analysed for prey captures and behavioural activity patterns.
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    Cape Town's domestic cats : prey and movement patterns in deep-urban and urban-edge areas
    (2010) George, Sharon; Simmons, Robert E; O'Riain, Justin
    Domestic and feral cats (Felis catus) have impacted negatively on native wildlife on both islands and on the mainland. Impacts range from a reduction in numbers of prey species to local extinctions, especially of birds on islands. This study provides the first data on the impacts of domestic cats on wildlife on the African mainland continent by comparing the diet and movement patterns of cats that live within urban areas with those of cats that live on the urban?edge adjacent to natural areas of Cape Town, South Africa. The findings suggest that domestic cats in urban areas of Cape Town pose a significant threat to wildlife, with indigenous small mammals most at risk. This agrees with many other studies carried out in New Zealand, Australia and the United Kingdom.
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    Causes and consequences of mortality and mutilation in the Cape Peninsula baboon population, South Africa
    (2009) Beamish, Esme Kilroy; O'Riain, Justin
    In the Cape Peninsula, South Africa, the population of chacma baboons (Papio ursinus) has become locally fragmented and geographically isolated from all other populations in the Western Cape. A census performed in 1999 revealed a baboon population under severe human predation pressure with high levels of permanent injury and mortality, in addition to an adult sex ratio strongly biased towards females. There was no data on the causes or the distribution of deaths and permanent injuries on the Peninsula to inform management decisions. The aim of this study was thus to: a) quantify the frequency, distribution and causes of permanent injuries (mutilations) and deaths within the Cape Peninsula baboon population, and b) to quantify whether mutilations, affect the behaviour, diet and reproductive success of baboons.
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    The conservation status and dynamics of a protected African lion Panthera leo population in Kafue National Park, Zambia
    (2014) Midlane, Neil; O'Riain, Justin; Hunter, Luke T B; Balme, Guy A
    The abundance of African lions Panthera leo has declined rapidly in recent decades, largely due to competition for space with growing human populations. The future persistence of the species in the wild therefore depends heavily on viable populations in large protected areas, where lions play key ecological and economic roles. Zambia is one of nine countries estimated to have over 1000 wild lions, and Kafue, its largest national park, is a key refuge for the species. In this thesis I aimed to address the paucity of management and conservation relevant data on Kafue's lion population. I first used a track-based occupancy survey to determine the broad-scale drivers of lion distribution in the park. My results did not support my a priori expectations of anthropogenic edge effects driving lion occupancy; instead favourable habitat emerged as the best predictor of dry season lion distribution. The lack of edge effects is likely a result of the uniform suppressive effect on prey biomass of ubiquitous illegal bushmeat hunting in Kafue. After using my occupancy results to stratify my study area, I tested the effectiveness and efficiency of two well-established survey methods, track counts and call-up surveys, by comparing the resulting density estimates with that of a reference sample of GPS-collared lions in the study area. Accuracy of the two results was comparable, but the call-up estimate was more precise. However, call-up surveys are subject to variation in response rates that is difficult to quantify. I thus recommend that track count surveys are more suitable for monitoring lion population trends in Kafue. I further provide the first robust density estimate for northern Kafue of 1.83 lions (>1yr old) per 100 km2. Understanding how animals use space is fundamental to their conservation. I therefore used GPS collars to investigate lion spatial ecology at a finer scale, and the effects thereon of the seasonal flooding of large parts of Kafue. Home range sizes were comparable to those of other lion populations in the region. However, seasonal inundation caused lions to expand home ranges, travel greater distances and shift away from favourable habitat in the wet season, potentially contributing to apparent high cub mortality rates. The combination of these factors may limit the resilience of the population in the face of identified local anthropogenic threats (i.e. illegal hunting of ungulates and lions, legal trophy hunting of lions and frequent, uncontrolled bushfires). I provide both direct and indirect evidence of such threats, and conclude that lion abundance in Kafue is limited primarily by the suppressed prey population, while the extent and regularity of bushfires may also have adverse effects. I recommend stronger enforcement of existing regulations pertaining to illegal hunting and fires, and the implementation of recently developed monitoring software to improve the efficiency and effectiveness of limited law enforcement resources. I further conclude that lion hunting quotas were excessive prior to the 2013 ban on hunting in Zambia, and suggest that the ban remain in place for at least three years to enable adequate recovery of the population. If the Zambian government elects to lift the ban, I propose a total combined quota of 5.25 lions per annum for the hunting concessions surrounding Kafue. I further recommend the implementation of strict age-based regulations within a robust adaptive management framework, based on the best available scientific data, to ensure the sustainability of harvest. To evaluate the effectiveness of such management interventions I propose long-term monitoring of lion abundance and distribution in Kafue using annual track count surveys. This study highlights that even the largest of Africa's national parks cannot ensure the survival of flagship apex carnivores. My findings and recommendations may be applicable to other wild lion populations in large protected areas where data paucity limits management effectiveness. Understanding and managing threats to these protected areas at the appropriate scale is critical if they are to meet their conservation objectives and ultimately ensure the persistence of wild lion populations.
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    Determinants of predator abundance in northern KwaZulu-Natal: top-down or bottom-up?
    (2014) Woodgate, Zoe Anne; Balme, Guy A; O'Riain, Justin
    As protected areas ultimately aim to successfully conserve natural predator populations, an understanding of the non-anthropogenic drivers of their population change is critical. Both bottom-up (e.g. food limitation, competition) and top-down (e.g. predation, interference) processes play an important role in structuring predator guilds, yet there is a poor understanding of their relative importance. Here, I investigated whether the relative abundance of mesopredators, facultative scavengers, and an apex predator were affected primarily by bottom-up processes (prey abundance) or by top-down processes (predator abundance), or a combination of the two. Central to this study was elucidating the complex relationship between mesopredators and apex predators. Caracal (Caracal caracal), blackbacked jackal (Canis mesomelas), sidestriped jackal (Canis adustus), honey badger (Mellivora capensis) and serval (Leptailurus serval) were classed together as Mesopredators. Facultative scavengers included two hyaena species (spotted Crocuta crocuta and brownhyaena Hyaena brunnea). Leopards (Panthera pardus) were included as an example of an apex predator. Data was obtained from camera-trap surveys conducted in four protected areas located in northern KwaZulu-Natal (South Africa). Results of both a nested analysis of variance and generalised linear mixed models revealed that there was no mesopredator suppression present in protected areas with complete predator guild. In addition, prey and similarly sized predator relative abundance indices (RAIs) had a significant positive effect on mesopredator, hyaena and leopard RAI. The findings suggest that bottom-up drivers are more important than top-down processes in determining the relative abundance of mammalian predators in these protected areas. My study highlights the importance of monitoring prey populations in a protected area when attempting to successfully manage mammalian predator trophic guilds.
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    The effects of white shark presence on the behaviour of Cape fur seals at Geyser Rock, Gansbaai, South Africa
    (2013) Wcisel, Michelle; O'Riain, Justin; De Vos, Alta; Underhill, Les
    Predators and the risk associated with their presence may affect group composition, group size, movement patterns, and habitat use of prey species. The removal of predators, or their reintroduction following long periods of absence, equally can have profound impacts on their prey, triggering ecological cascades and ultimately shaping the biota of entire landscapes. While such processes are well documented in terrestrial ecosystems, similar results are absent in the marine realm, largely due to logistical difficulty. One exception to this is the study of white shark and seal interactions at coastal island rookeries, where white shark presence is seasonal, and seals exhibit marked behavioural differences between seasons. What is lacking from these studies, however, is how subsurface habitat around the islands, specifically refugia, may influence the behaviour of seals and their interactions with white sharks. I address this challenge by comparing both seal movement patterns and shark-seal interactions at Geyser Rock, Gansbaai with the established seal and shark patterns at Seal Island, False Bay. White sharks aggregate at both islands during the austral winter and seals encounter these aggregations when commuting to and from their respective rookeries to offshore foraging areas. The seascape around Geyser Rock is comparably more featured, including kelp beds and extensive shallow (5-10m depth) reef systems, whereas Seal Island is largely featureless, with neither extensive kelp nor reefs. At Geyser Rock, predations by white sharks were rarely observed (0.1 predations/hour) compared to Seal Island (1.24 predations/hour) and lacked the focused spatiotemporal peak at sunrise to the south of the island. Seals at Geyser Rock did not show a relationship between group formation and season, which was clearly demonstrated at Seal Island. This suggests that seals at Geyser Rock may be less reliant on group formation (safety in numbers) and selfish herd tactics within such groups to reduce predation risk. Rather, seals at Geyser Rock avoided deep open water patches during winter and shifted their movement patterns to and from the island to sectors with greater subsurface habitat heterogeneity. While I was limited in quantifying spatiotemporal patterns of predation risk around Geyser Rock (predation events were rare and widely dispersed), these results strongly suggest that seals actively avoid deep open water and show a preference for high structural complexity sectors during the risky winter months when shark presence is highest. This finding represents a habitat-escape tactic unidentified in previously studied white shark/pinniped systems. Together these results provide empirical support for both the risk-allocation hypothesis and refugia hypotheses within marine predator-prey systems.
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    Estimating spotted hyaena (Crocuta crocuta) population density using camera trap data in a spatially-explicit capture-recapture framework
    (2014) De Blocq , Andrew Dirk; O'Riain, Justin; Balme, Guy A
    Species-specific population data are important for the effective management and conservation of wildlife populations within protected areas. However such data are often logistically difficult and expensive to attain for species that are rare and have large ranges. Camera trap surveys provide a non-invasive, inexpensive and effective method for obtaining population level data on wildlife species. Provided that species can be individually identified, a photographic capture-recapture framework can be used to provide density estimates. Spatially-explicit capture-recapture (SECR) models have recently been developed, and are currently considered the most robust method for analysing capture-recapture data. Camera trap data sourced from a leopard survey performed in uMkhuze Game Reserve, KwaZulu-Natal, South Africa, was analysed using SPACECAP, a Bayesian inference-based SECR modelling program. Overall hyaena density for the reserve was estimated at 10.59 (sd=2.10) hyaenas/100 km2, which is comparable to estimates obtained using other methods for this reserve and some other protected areas in southern Africa. SECR methods are typically conservative in comparison to other methods of measuring large carnivore populations, which is somewhat supported by higher estimates in other nearby reserves. However, large gaps in time between studies and the variety of historical methods used confound comparisons between estimates. The findings from this study provide support for both camera trap surveys and SECR models in terms of deriving robust population data for spotted hyaenas and other individually recognisable species. Such data allows for studies on the drivers of population and distribution changes for such species in addition to temporal and spatial activity patterns and habitat preference for select species. The generation of accurate population data for ecologically important predators provides reserve managers with robust data upon which to make informed management decisions. This study shows that estimates for spotted hyaenas can be produced from an existing survey of leopards, which makes photographic capture-recapture methods a sensible and cost-effective option for the less charismatic species. The implementation of standardized and scientifically robust population estimation methods such as SECR using camera trap data would contribute appreciably to the conservation of important wildlife species and the ecological processes they support.
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    Gastrointestinal parasite infections in Chacma baboons (Papio ursinus) of the Cape Peninsula, South Africa : the influence of individual, group and anthropogenic factors
    (2009) Ravasi, Damiana Francesca Celine; O'Riain, Justin
    This study investigates whether anthropogenic changes in the Cape Peninsula, South Africa, have affected gastrointestinal parasite infections in a free-living population of chacma baboons (Papio ursinus). Data on parasite diversity and prevalence were obtained from 616 faecal samples collected from over 350 individuals in eight troops (six from the Cape Peninsula, one from Pringle Bay, and one from Wildcliff Nature Reserve) between July 2006 and August 2007.
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    Gastrointestinal Parasite infections in Chacma Baboons (Papio ursinus) of the Cape Peninsula, South Africa: the influence of individual, group, and anthropogenic factors
    (2009) Ravasi, Damiana Francesca Celine; O'Riain, Justin
    Habitat disturbance can lead to the alteration of host-parasite dynamics and ultimately influence the mechanisms that regulate wildlife populations. This study investigates whether anthropogenic changes in the Cape Peninsula, South Africa, have affected gastrointestinal parasite infections in a free-living population of chacma baboons (Papio ursinus). Data on parasite diversity and prevalence were obtained from 616 faecal samples collected from over 350 individuals in eight troops (six from the Cape Peninsula, one from Pringle Bay, and one from Wildcliff Nature Reserve) between July 2006 and August 2007. Faeces were processed using a modified formalin-ether sedimentation technique and helminth eggs and protozoan cysts were identified. The helminth and protozoan fauna of the Cape Peninsula baboon population was similar to both neighbouring and geographically disparate chacma baboon populations in South Africa. Distribution of helminth infection within a troop was influenced by the age of the host but not by other individual-level traits (i.e., gender and female reproductive and social status). Protozoan and helminth species richness was highest in the troop (Kanonkop) with the least human contact and the most pristine indigenous vegetation and was lowest in the troop (Tokai) with the highest levels of anthropogenic disturbance. Prevalences of the nematodes Trichuris sp. and Oesophagostomum sp. were highest in the troop (Da Gama Park) with the most frequent human interactions. A series of potential host-intrinsic (e.g., host sex and age) and host-extrinsic (e.g., troop characteristics, climate) determinants of host-parasite dynamics were investigated but failed to explain the observed inter-troop variations in parasite infections. Molecular analyses of the ubiquitous and highly prevalent nematode, Trichuris sp., provided evidence of two genetically distinct Trichuris species, including a newly identified baboon parasite, named T. papionis, and another that strongly resembles (91% similarity between ITS1-5.8S rDNA-ITS2 sequences) the human T. trichiura. The latter finding provides the first evidence of a likely reverse zoonotic infection of baboons with human parasites and provides management authorities with a strong motivation to restrict the spatial overlap between the humans and baboons in the Cape Peninsula and indeed other regions of the Western Cape. Keywords: Papio ursinus - chacma baboon - parasites - urbanization - Trichuris - molecular
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    Genetic admixture of Kruger National Park black rhino (Diceros bicornis minor): conservation implications
    (2020) Stanbridge, Deborah; O'Riain, Justin; Le Roex, Nikki
    Black rhinoceroses (Diceros bicornis) have been extirpated from most of their historic range with the remaining individuals (ca. 5200) living in geographically isolated populations. Management priorities include creating new populations whilst maintaining genetic diversity and promoting gene flow between existing isolated populations. Such objectives are however currently hindered by a lack of comparative/reference data on levels of diversity, relatedness and inbreeding in a large, free-ranging black rhinoceros population. Here I attempt to address this gap in our knowledge by investigating the genetic diversity of the black rhinoceros Diceros bicornis minor within Kruger National Park (the largest free-ranging population of this subspecies) using nuclear and mitochondrial DNA. I compared the diversity of this founded population with the two source populations (KwaZulu-Natal, South Africa and Zimbabwe) using published studies, and evaluate the relative contribution of source lineages relative to the proportion of original founders. Analysis of the mtDNA control region revealed four haplotypes, with moderate haplotype and nucleotide diversity (h=0.48 (± 0.05 SD); π= 0.29%). Data from 13 microsatellite loci revealed moderate to high levels of genetic variation (number of alleles = 4.92 ± 0.90, effective number of alleles = 2.26 ± 0.25, observed heterozygosity = 0.50 ± 0.04, expected heterozygosity = 0.51 ± 0.04), low mean pairwise relatedness (r = -0.03), a low inbreeding coefficient (Fis = 0.04) and no evidence of genetic structuring. Diversity levels within the Kruger black rhinoceros population were high compared to levels reported in black rhinoceroses originating in KwaZulu-Natal and similar to those reported in individuals originating in Zimbabwe. Results show that 40-60% of the Zimbabwean lineages are represented in the Kruger population which is a noticeable increase in the relative contribution of the Zimbabwe founder population. The data provided by this study can be used to guide management and conservation decisions regarding maximising genetic variability across the subspecies. Furthermore, given the encouraging levels of genetic diversity observed, the Kruger black rhinoceros population would be an ideal source population for supplementation of genetically depauperate populations or creating new populations. Finally, these findings demonstrate a positive outcome in mixing the KwaZulu-Natal and Zimbabwe gene pools, with evidence that the founder Kruger black rhinoceros population has been genetically rescued from the low diversity seen in the KwaZulu-Natal black rhinoceroses in South Africa.
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    Hormonal aspects of reproductive suppression in the naked mole-rat, Heterocephalus glaber
    (2006) Tuomi, Erin Bianca; O'Riain, Justin
    Subordinate, female naked mole-rats (Heterocephalus g/aber) are anovulatory as a result of extremely low luteinising hormone (LH) levels. Evidence suggests that aggression from the dominant female naked mole-rat directed towards subordinates could produce these lowered levels of LH. This study examined two potential hormonal pathways of reproductive suppression in this species: endogenous opioid peptides and cortisol.
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    The impact of White Shark (Carcharodon carcharias) sightings and attacks on recreational water use patterns in False Bay
    (2013) Engelbrecht, Tamlyn; O'Riain, Justin; Kock, AA
    White sharks (Carcharodon carcharias) are apex predators that play an important role in the structure and functioning of marine ecosystems. However, despite both their ecological importance and threatened conservation status this species is still subject to lethal control to reduce the risks of predation for recreational water users. The Shark Spotter program, pioneered in False Bay, South Africa, proposes a non-lethal alternative to reducing predation risk. This program aims to balance the needs of people with white shark conservation by actively reducing conflict between recreational water users and sharks. In this study I establish the extent of spatial overlap between white sharks and water users at two popular recreational beaches in False Bay (Fish Hoek and Muizenberg), and investigate how shark sightings (accompanied by warning flags and/or a siren) as well as attacks influence water use patterns amongst bathers, surfers and paddlers. In the period from 2006 to 2012, the total number of shark sightings recorded was 531 at Muizenberg and 322 at Fish Hoek, with a notable increase in sightings at both beaches in recent years. Shark sightings were rare in winter increasing into the spring and summer months when recreational use of the inshore was highest. Daily shark sightings peaked at midday to late afternoon at both beaches, coinciding with peak numbers of water users. The response of water users to warnings of shark presence by the Shark Spotters was only found to be significant in cases where the siren was sounded by the shark spotters, and in the absence of a siren warning flags had little impact on average numbers of water users. The occurrence of a fatal shark attack was found to a) increase response of water users to auditory warnings (when the siren is sounded) but not visual warnings (warning flags unaccompanied by a siren); and b) reduce the average number of water users present at both beaches for at least three months following the fatal incident. Annual averages of water users at Muizenberg beach also reflected this pattern, with a general reduction in water use in years with attacks compared to those without. These findings indicate that the Shark Spotter program is effective in mitigating conflict between water users and white sharks through auditory warnings and subsequent beach clearing in the event of a shark sighting; however the lack of response by water users in the absence of a siren and after long periods without an attack remains a challenge to the effectiveness of the program. The large spatial overlap between white sharks and water users, as well as the increasing number of shark sightings at both beaches, emphasises the need for continuous revision and improvement of mitigation strategies to prevent conflict between white sharks and water users in False Bay.
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    Infection of two distinct Trichuris sp. genotypes within and among baboon (Papio ursinus) troops on the Cape Peninsula, South Africa
    (2013) Moxley, Courtney; Illing, Nicola; O'Riain, Justin
    The chacma baboon (Papio ursinus) population on the Cape Peninsula, South Africa is divided into 16 geographically isolated troops, 14 of which are classified as being commensal with humans. Regular contact with humans in urban and agricultural settings may have increased the risk of transmission of the different parasite species identified within this population. The aim of the study was to identify whether two previously-identified genotypes of the whipworm, Trichuris sp., infect the same individual baboon simultaneously and whether both genotypes infect baboons of different troops on the Peninsula. Genomic DNA was extracted from adult Trichuris worms extracted from the gastrointestinal tract of six baboons from five different troops on the Peninsula. Two sets of primers were designed to amplify different sized products of the ITS1-5.8S-ITS2 region of the ribosomal DNA through PCR. Diagnostic PCR revealed the DG genotype among two Trichuris sp. specimens in a baboon from an unknown troop, while the CP-GOB genotype was observed among five specimens within a baboon from the Groot Olifantsbos troop. Sequence data confirmed the presence of a single genotype in each troop. This study suggests that the genotypes are specific to baboon troops but the potential for both genotypes to infect baboons within troops on the Peninsula cannot be ruled out. Knowledge of the specificity of the Trichuris genotypes to baboon hosts of different troops may inform our understanding of the evolution of diversity within this genus. Future research into the transmission of both genotypes within and between troops may also highlight the potential for two distinct species of Trichuris to exist among the baboons. Considering the close contact between baboons and humans on the Peninsula, clarification on host specificity of either genotype will also be important for managing zoonoses and preventing break-outs of infectious diseases between the species.
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    Pup ontogeny and factors influencing behavioural and morphological variation in naked mole-rats, Heterocephalus glaber (Rodentia, Bathyergidae)
    (1996) O'Riain, Justin; Jarvis, J U M
    A long term behavioural study was undertaken on laboratory-reared naked mole-rats. The main objective of the study was to provide a detailed qualitative and quantitative description of the behavioural and morphological development of naked mole-rats from birth through to adulthood. This study laid an empirical foundation for the subsequent testing of hypotheses pertaining to within and between colony conflict as well as for a study on the existence of a rare dispersal phenotype within colonies.
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    Pup provisioning and artificial pack formation in African wild dog Lycaon pictus in South Africa
    (2009) Potgieter, Katherine; O'Riain, Justin; Davies-Mostert, H T
    Wild dog Lacaon pictus are obligate cooperative breeders with nulliparous helpers contributing to the rearing of a dominant pair's young through pup-provisioning and defence agianst predators. Despite the importance of allo-parental care to the survival of pups and the persistance of packs, few studies have addressed the group or individual level factors that influence helping in wild dogs. In this study we use data collected as part of a long-term project in the Kruger National Park (KNP) to provide the first detailed analysis on the relative contribution to pup rearing of dogs both within and between packs in the KNP.
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    Seals and Sharks
    (2014-09-12) O'Riain, Justin; Neary, Tim
    In this radio broadcast, Justin o' Riain discusses shark and seal interactions in the False Bay/Seal Island area, focusing on predator-prey interactions and predation behaviour. Additional topics discussed are the seals' response to aggressive predation behaviour, including travelling strategies and learning patterns among young seals. Ethology of seals and sharks, specifically focusing on predator-prey relations, avoidance and predation strategies. Image provided courtesy of Christopher under a Creative Commons Attribution 2.0 Generic license.
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    Seasonal patterns in body temperature and behaviour in Cape ground squirrels, Xerus inauris, living in a semi-arid environment
    (2009) Wilson, Wendy Anne; O'Riain, Justin; Fuller, A
    Miniature temperature-sensitive data loggers were implanted into the abdominal cavities of 16 free-ranging Cape ground squirrels, Xerus inauris, to investigate seasonal body temperature patterns. Data loggers recorded body temperature at 5-min intervals while microclimate variables were recorded in situ at 15 minute intervals. The behaviour of the study animals was recorded using 5-min scan samples throughout the day. These data were collected for eight Cape ground squirrels for 27 and 28 days during the austral winter and summer respectively.
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    The spatial ecology of chacma baboons (Papio ursinus) in the Cape Peninusula, South Africa: towards improved management and conservation strategies
    (2011) Hoffman, Tali S; O'Riain, Justin
    Competition for space between humans and wildlife is prevalent worldwide. In the Cape Peninsula, South Africa, extensive land transformation has geographically isolated, fragmented and reduced the size of the local chacma baboon population and is perceived to be a major driver of human-baboon conflict. However, no data on baboon landscape use exist to verify this perception. I studied the spatial ecology of this population, identifying baboon land use patterns, determining the drivers of intrapopulation variation in spatial ecology and investigating how spatial variables could inform baboon management efforts to reduce human-baboon conflict.