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Diversity of butterflies and day-flying moths in urban habitat fragments, south-western AustraliaWilliams, Matthew R. January 2009 (has links)
This study adapted and developed methods of assessing and modelling biodiversity of butterflies and day-flying moths in habitat fragments, and determined those factors affecting their presence, abundance and species richness in a sample of 46 isolated urban remnants in south-west Western Australia. The specific objectives were to: (i) assess the effectiveness of transect–based sampling to quantify the species richness of habitat fragments; (ii) examine patterns of species richness in habitat fragments and quantify the detectability of each species recorded; (iii) review and rationalize the methods used to fit species–area–habitat models; and (iv) model species incidence, abundance and total richness of butterflies in urban habitat fragments and determine implications and priorities for their conservation. / These objectives were achieved and the principal findings of the research are: (i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants. / (i) The transect method provides an accurate assessment of butterfly species richness in isolates provided that the level of sampling (proportion of area surveyed) is adequate, that sufficient surveys are conducted during the flight season to ensure high levels of detectability, and that surveys are conducted at appropriate times and during suitable weather conditions. Although randomly placed transects are preferable, logistic constraints often dictate the use of existing pathways, roadsides or management tracks – which requires the use of longer transects but is more practical in urban remnants. / (iii) Almost a century of fitting species–area curves has failed to produce agreement on which function is the best model of the relationship. Many of the proposed functions are identical, special cases of others or have arisen from transcription errors. Empirical comparison of these functions requires methods suited to the distribution of species number such as the generalized linear model, method of maximum likelihood and the information-theoretic approach, and proper attention to covariates and their interactions. / (iv) Site area and vegetation condition were the dominant determinants of the presence, abundance and total species richness of resident butterflies and day-active moths in 46 urban habitat fragments in south-west Western Australia. Larger sites with more high quality (undisturbed) vegetation favoured 16 of 20 native species and only one benefited from disturbance. A further nine species not sufficiently widespread or abundant to enable individual analysis were collectively more prevalent in larger sites. Resource quality and quantity dominated the patterns of site occupancy, and increased site connectivity did not favour any species – results consistent with habitat resources, not metapopulation effects, determining current distribution patterns. As expected, the presence of non-resident species was unaffected by site area. The total number of resident species at each site reflected the collective responses of the individual species: increasing with area and declining with vegetation disturbance. The effects of area and vegetation quality were not simply additive: disturbance had a far greater impact on small remnants. This interaction is inconsistent with the area per se hypothesis: in the absence of disturbance there was no evidence of a species–area effect. / This study is the first comprehensive, quantitative assessment of the distribution and ecology of butterflies and day-flying moths in Australian urban habitat fragments and provides a baseline against which future changes in species distributions may be measured. The results have important implications for the conservation of butterflies and day-flying moths in the region. Maintenance of vegetation quality is of paramount importance and is vital in smaller remnants. Large remnants, being less susceptible to local extinctions, will be essential for the persistence of many species. Many functions have been proposed to model the species–area relationship but empirical comparisons have been hindered by methodological problems – this study conducted a re-examination of the relationship and presents an appropriate framework to compare functions. This study is also one of few to demonstrate and quantify the importance of interactions in explaining patterns of species richness and should stimulate future research into the importance of these effects.
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The elusive clean machine : rational order and play in a public railwayEvans, Michaela Skye January 2009 (has links)
[Truncated abstract] Rational order and play are often conceptualised as oppositional forces. In modern urban life especially, rational order is presented as destructive of a playful orientation towards life eschewing mystery through coherence, spontaneity through predictability, and contingency through systematic planning. In turn, the postmodern debate often asserts the reinvigoration of free, playful, and contingent individuals whose collective acts are destructive of the rationality of modern order with the present, in contrast to the past, offering a condition of enduring and unremitting uncertainty. This thesis explores the dynamic relation between rational order and play in urban society through an ethnographic account of a public commuter railway in Perth, Western Australia. Notwithstanding this ethnographic setting, the thesis addresses questions of broader significance through an analysis of the railway as an instance of public space and state techno-bureaucratic order. I investigate the creative process through which the state attempts to standardise the various operational components of the railway as well as the reasons underpinning the state's desire to produce what I term a 'clean machine'. In turn, I investigate how differentially positioned actors live within this carefully crafted machine. I do so by following the stories, experiences, and practices of: government administrators charged with building the railway; the managers who oversee the network's operation; the staff members who operate trains, clean stations, and discipline passengers; and the railway's end-users, including passengers and graffiti artists. ... In examining the two tensions of rational order/play and revelation/ concealment, I attempt to explicate how it is that people experience life as simultaneously coherent and serendipitous. In the thesis, I document the ways in which railway officials, passengers, and graffiti artists express a pervasive ambivalence towards their experience of the railway system. On the one hand, these actors experience the railway as a system of constraint that produces 'robotic' behaviours and automated transactions. On the other, they see the railway as a liberating space that enables autonomous expression and spontaneous interaction. By examining these contending experiences and associated sentiments, I highlight the railway as a stimulating site within which to explore the meaning and significance of urban modernity. Lastly, this thesis contributes to debate on the challenges posed by the character of contemporary social processes to anthropological research methodology. I illustrate the utility of such methods as written and photographic diaries as well as mental-mapping exercises, but primarily advocate the documentary and analytical advantages of participant observation in a mobile field-site. I assert that while participant observation poses a number of personal and professional challenges in this setting, these challenges uncover the stimulating complexity of contemporary urban life. To this end, I contest emergent academic commentary that propounds the destabilisation of anthropological techniques in what is frequently described as an equally destabilised world.
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To hunt and to hold : Martu Aboriginal people's uses and knowledge of their country, with implications for co-management in Karlamilyi (Rudall River) National Park and the Great Sandy Desert, Western AustraliaWalsh, Fiona Jane, January 2009 (has links)
[Truncated abstract] This ethnoecological study examines land uses by modern Martu Aboriginal people on their country. They occupy very remote settlementsParnngurr, Punmu and Kunawarritjiin the Great and Little Sandy Deserts. In 1990, their country included Crown Lands and Rudall River National Park. The study investigated the proposition that the knowledge and practices of Martu were of direct relevance to ecosystem processes and national park management. This research commenced in the wider Australian research context of the late 1980s early 90s when prevailing questions were about the role of customary harvest within contemporary Aboriginal society (Altman 1987; Devitt 1988) and the sustainability of species-specific harvests by Australian indigenous people (Bomford & Caughley 1996). Separately, there was a national line of enquiry into Aboriginal roles in natural resource and protected area management (Williams & Hunn 1986; Birckhead et al. 1992). The field work underpinning this study was done in 19861988 and quantitative data collected in 1990 whilst the researcher lived on Martu settlements. Ethnographic information was gathered from informal discussions, semi-structured interviews and participant observation on trips undertaken by Martu. A variety of parameters was recorded for each trip in 1990. On trips accompanied by the researcher, details on the plant and animal species collected were quantified. Martu knowledge and observations of Martu behaviour are interpreted in terms of the variety of land uses conducted and transport strategies including vehicle use; the significance of different species collected; socio-economic features of bush food collection; spatio-temporal patterns of foraging; and, the 'management' of species and lands by Martu. The research found that in 1990, hunting and gathering were major activities within the suite of land uses practiced by Martu. At least 40% of trips from the settlements were principally to hunt. More than 43 animal species and 37 plant food species were reported to be collected during the study; additionally, species were gathered for firewood, medicines and timber artefacts. Customary harvesting persisted because of the need for sustenance, particularly when there were low store supplies, as well as other reasons. The weight of bush meats hunted at least equalled and, occasionally, was three times greater than the weights of store meats available to Parnngurr residents. ... Paradoxically, hunting was a subject of significant difference despite it being the principal activity driving Martu expertise and practice. There is potential for comanagement in the National Park but it remains contingent on many factors between both Martu and DEC as well as external to them. The dissertation suggests practical strategies to enhance co-management.
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Erysipelothrix rhusiopathiae : epidemiology, virulence factors and neuraminidase studiesWang, Qinning January 2003 (has links)
Erysipelothrix rhusiopathiae, a Gram-positive bacillus, has long been an important pathogen in veterinary medicine as well as a cause of serious disease in humans. Infections caused by this organism have economic impact on animal industries, causing erysipelas in swine and morbidities in other farmed animals. Human infections are commonly erysipeloid (skin cellulitis) and occasionally septicaemia or endocarditis. Little is known of the diagnosis, epidemiology and pathogenesis of such infections in Western Australia. The aims of this thesis were to establish new diagnostic techniques for the detection and recovery of E. rhusiopathiae, to describe the epidemiology of Erysipelothrix infection in Western Australia in humans and animals, and to characterize virulence-associated characteristics, especially focusing on the neuraminidase produced by the organism. A protocol using 48 h Brain Heart Infusion enrichment followed by subculture to selective agar containing antibiotics achieved the highest recovery rate of 37% in a seafood survey. Twentyone isolates of Erysipelothrix spp., of which 19 were identified as E. rhusiopathiae, were obtained. Two published PCR assays for differentiating E. rhusiopathiae and other Erysipelothrix species were evaluated and the best PCR detection rate achieved was 67% following selective enrichment. The PCR method was 50% more sensitive than the culture method. Epidemiological surveys using the above methods showed that E. rhusiopathiae infection is present in farmed animals in Western Australia. The PCR positive frequencies (3.3-3.7%) and isolate recovery rate (2.8-3.3%) in samples from pig and sheep abattoirs and carcass washings indicate a potential threat to the economy of the farmed animal industry as well as a public health concern with the occurrence of E. rhusiopathiae in meat for consumption. Positive PCR results (1.1%) from human skin swabs of patients with cellulitis and wounds may suggest the existence of Erysipelothrix colonization in the general population. Genetic relatedness of 92 isolates of Erysipelothrix species from various sources was analyzed and a total of 64 distinct PFGE patterns identified. Isolates were further classified into 20 clonal groups based on pattern similarities, and most E. rhusiopathiae were clustered into six groups. A few patterns of other Erysipelothrix species were clustered into separate groups from E. rhusiopathiae but shared greater than 70% similarity with E. rhusiopathiae. The genetic relatedness of colonial variants was well demonstrated using this method. PFGE typing promises to be a useful tool for epidemiological and taxonomic studies of Erysipelothrix. Several virulence-associated factors were characterized in 86 isolates of Erysipelothrix spp. A rapid and sensitive peanut lectin hemagglutination assay for neuraminidase was developed and the influence of media, incubation conditions and pH on the production of the enzyme was investigated. All 61 isolates of E. rhusiopathiae produced neuraminidase in cooked meat broth with titres between 1:10 and 1:320, with no significant difference in titre among isolates from different sources. The enzyme activity was not detected in non-pathogenic Erysipelothrix spp. Capsule was produced by 78.7% of isolates of E. rhusiopathiae but not by other species, while both hyaluronidase and haemolysin were produced by non-pathogenic Erysipelothrix spp. It was concluded that neuraminidase and capsule are most likely to be virulence factors of E. rhusiopathiae. The gene encoding neuraminidase was cloned from the type strain E. rhusiopathiae ATCC 19414. The cloned fragment was a functional partial nanH gene with a mol% G+C of 39.7. The predicted amino acid sequence displayed homology with many microbial neuraminidases and contained conserved sequences found in most bacterial neuraminidases. Southern hybridization experiments demonstrated that the gene was present as a single copy on the bacterial genomic DNA. A neuraminidasenegative mutant vector was constructed by insertional inactivation using a tetM cassette. This has provided starting material for developing a neuraminidase-deficient E. rhusiopathiae mutant, which will permit the study of the role of neuraminidase in pathogenesis. Based on the cloned sequence, a sensitive neuraminidase-specific nested PCR technique was designed and optimized. The specificity was tested in 61 isolates of E. rhusiopathiae, 25 Erysipelothrix species, and 62 other species of neuraminidaseproducing and non-producing bacteria. All isolates of E. rhusiopathiae were PCR positive and all other bacteria were negative; thus this PCR is a highly specific method suitable for application in clinical investigations of Erysipelothrix infection. In conclusion, the present study has contributed new knowledge of the biology of Erysipelothrix spp. and current occurrence of Erysipelothrix infections in Western Australia, as well as to the understanding of pathogenesis of E. rhusiopathiae. Development of several new cultural and molecular approaches in combination with other established techniques will facilitate future studies of the epidemiology, taxonomy and pathogenesis of this bacterial species.
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Physical processes controlling circulation and frontal zones in Shark Bay, Western AustraliaNahas, Elizabeth Leila January 2005 (has links)
Shark Bay is a large inverse estuary, located in Western Australia. It has a number of unique habitats that support important species. The dynamics of circulation in Shark Bay have an influence on the species that inhabit the region, on small, local scales as well as on large Bay-wide scales. Numerical modeling and field data were used to examine small-scale dynamics in relation to an important recreational fish, pink snapper (Pagrus auratus). Icthyoplankton surveys collected and recorded egg density in regions where snapper are found. A barotropic three-dimensional hydrodynamic model was coupled with a two-dimensional Lagrangian particle-tracking program to simulate the passive transport of eggs through regions where spawning is known to occur. Circulation modeling results indicated residual flows on small scales that served to retain the eggs in the region where they were originally spawned. Results corroborate genetic work on adult snapper, which found no evidence intermixing of populations in Shark Bay. The numerical model was then further refined to run in a baroclinic mode. Simulations of salinity and temperature gradients were used to recreate frontal systems in Shark Bay. Frontal regions divide the Bay into a northern and a southern section as well as separate it from the ocean. Application of an analytical method for calculating front locations was consistent with the observed results and indicated that the primary forces determining frontal locations in the Bay are tides and gravitational circulation. Winds are a secondary influence, and solar heating is minimal in influence
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Environmental response to burrowing seabird colonies : a study in ecosystem engineeringBancroft, Wesley J. January 2004 (has links)
[Truncated abstract] Ecosystem engineers are organisms that physically modify habitat in a manner that modulate resource flows and species within ecosystems. Ecosystem engineering is distinct from classical interactions (competition, predation, parasitism and mutualism) in that it does not involve direct trophic exchange between organisms. The term ‘ecosystem engineer’ is a recently adopted one, and we are just beginning to investigate the occurrence and impact of engineers in ecosystems. My thesis explores the ecosystem engineering actions of Wedge-tailed Shearwaters, Puffinus pacificus, in a Mediterranean island, heathland ecosystem. I have approached this by (1) describing and quantifying the physical impact of these engineers, and (2) describing and quantifying the effects that these actions have on three major ecosystem components: the soil, the vascular plants, and the vertebrate fauna. Wedge-tailed Shearwaters are procellariid seabirds that excavate nesting burrows on offshore islands. The birds are colonial nesters, and on Rottnest Island, 17 km off the mainland coast of south-western Western Australia, their colonies have expanded considerably in recent decades. The expansion fits the trend observed in other tropicalorigin seabirds that breed in south-western Australia. In the last ten years, two new colonies have appeared (in a total of six) and the number of burrows on the island has almost doubled, to 11 745 ± 1320SE. In the same period the area occupied by the birds has increased by almost half ...
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Improving enhanced surveillance of notifiable enteric illnessesLeighton, Kim January 2005 (has links)
[Truncated abstract] Gastroenteritis is frequently associated with a food or water borne source and the investigation of such cases is undertaken to identify potential sources of infection. Where contaminated food or water are identified as the source of infection/intoxication, action may be taken to limit or prevent further people being affected, and in so doing limit costs to the health care system. This study was undertaken to determine if there is a more effective and efficient way to collect information from patients with certain enteric illnesses. This was based on a trial process of posting self-administered questionnaires with a reply-paid return envelope to the patient and compared with the existing process where local government Environmental Health Officers interview the patient and provide a report to the Department of Health. A limiting factor in the existing process is the time lapse between the onset of illness and follow-up by Environmental Health Officers (EHOs), which results in difficulties in contacting the patient and obtaining a dietary history. Furthermore, the existing system is resource intense, requiring officers to individually interview patients either in person or by telephone. The study was of those patients living in the Perth metropolitan area whose doctor notified the Department of Health that the patient had contracted any of three notifiable enteric illnesses (campylobacterosis, giardiasis or salmonellosis), and the patient was not part of a known outbreak and was assessed as not requiring urgent follow-up. The trial process was used for patients living in five local government areas and the return rate, timeliness of return and completeness of questionnaires in the trial process was compared with the reports returned under the existing process of investigation and reporting by EHOs from 24 metropolitan local government areas that were not part of the trial process. An estimate of the potential costs to local government and the Department of Health was undertaken for both the existing and trial processes of collecting information from patients. A survey of local government EHOs in the metropolitan area was also undertaken to assess the perception of EHOs about roles and responsibilities in the follow-up investigation, the use of the Enteric Disease Investigation Report (EDIR) and the limitations that they identified in the current investigation process.
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The use of remotely sensed data to analyse spatial and temporal trends in vegetation patchiness within rehabilitated bauxite mines in the Darling Range, W.A.Prananto, Agnes Kristina January 2006 (has links)
[Truncated abstract] The assessment of rehabilitation success is time consuming and costly for bauxite miners because large areas of land (~550 ha per year) are involved. In some cases, rehabilitation results in patches of bare or sparsely vegetated soil. This study uses remote sensing imagery to evaluate the growth of vegetation in rehabilitated bauxite mines in the Darling Range, W.A. This work has five aims, which are to (1) compare vegetation biomass within rehabilitated areas and nearby native forest; (2) analyse temporal changes in vegetation growth within the selected rehabilitated areas, in particular rehabilitated areas with patches of bare soil; (3) compare vegetation growth pre- and post- mining; (4) identify the best type of remotely sensed data for this particular study area, and (5) develop an index, which can classify the degree of vegetation patchiness within rehabilitated mine sites. This information will enable rehabilitation workers to identify patches in rehabilitated areas that may require further remediation. The study used RADARSAT, nine years of Normalised Difference Vegetation Index (NDVI) maps (extracted from LANDSAT TM multivariate imagery and Quickbird imagery) and aerial photographs to evaluate forty-seven ~1 ha study sites. Image and map analyses were conducted mainly using ESRI’s software ArcGIS 8.3 and ER Mapper 6.4. Ground truthing was carried out to confirm and recognise the causes of bare patches within the rehabilitated mine sites ... The results indicate that differences in rehabilitation management do not affect this index but the extent of bare patches does. Due to the sensitivity of radar imagery to surface roughness, rehabilitated areas cannot be distinguished from the native forest using radar images. A building (crusher) appears to be the same as mature vegetation. Knowledge of the features in an area is therefore crucial when utilising RADARSAT. The beam elevation angle and profile of the RADARSAT image used, made superimposition of radar and optical imageries impossible. Speckle noise in RADARSAT images made it impossible to detect relatively small bare patches. In addition, the many cloud free days in Western Australia make optical imaging possible so that the ability of radar imagery to penetrate cloud is redundant for this type of study.
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The effect of price and health information in shifting young children [sic] preference towards healthier foodDahari, Zainurin January 2007 (has links)
Young children have becoming an important target by marketers. Marketers have used many strategies to influence their food choices including advertising and free gifts. According to literature, young children, are cognitively vulnerable and may make unhealthy decisions about their food choices that could lead to serious problems associated with being overweight and obese. This thesis examines whether price and health claim information can shift young childrens' choices towards healthier foods. Most of the previous published research literature has focused on adults. Those findings, using surveys and experiments, suggest that adults' food preferences and choices can be influenced by setting price and by providing health information. These findings suggest that these strategies may have a potential effect in young children decision making. The literature on Children Socialization and Information Processing Theory in consumer behaviour suggests that most young children under 8 are not cognitively skilled to use price and health claim information for their decision making. Nonetheless, most 5 to 8 year olds are making purchases of food at their school canteen several times a week. In order to test for the effects of price and nutrition information, several experiments that used discrete choice modelling were conducted to determine their choices, the reliability of their choices and the between their experimental choice behaviour and their choice in the market place. More than one hundred young children, aged from five to eight years old, completed the discrete choice experiments conducted in two primary schools in the suburbs of Perth. The choice experiments on subjects that had previous experience with the food items, but did not know their relative nutritional value, showed a strong positive effect of price. In other words, higher priced options were often in more demand. Although this may appear a poor response to price by an observer, children have little knowledge of food costs, so they may use price as a surrogate for quality. Price level was also a main effect in reducing the share of unhealthy choices. The results of the analyses also show that young children can provide reliable choice decisions within 5 months of experiment. However, their experimental choices were not associated with their later choices in the canteen. These findings provide evidence of the effectiveness of price and health claim information in changing young childrens' preference toward healthy choices, and the potential usefulness of using discrete choice techniques to shift children to more healthy food options.
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Human impacts on Australian sea lions, Neophoca cinerea, hauled out on Carnac Island (Perth, Western Australia): implications for wildlife and tourism managementjporsini@bigpond.net.au, Jean-Paul Orsini January 2004 (has links)
Over the last 15 years, pinniped tourism has experienced a rapid growth in the Southern Hemisphere, and particularly in Australia and New Zealand where at least four sites attract more than 100,000 visitors per year. Tourism focused on the Australian sea lion (Neophoca cinerea), a protected species endemic to Australia, occurs in at least nine sites in South Australia and Western Australia. Australian sea lions haul out on several offshore islands in the Perth region.
Carnac Island Nature Reserve is one of the main sites where people can view sea lions near Perth, either during recreational activities or on commercial tours.
This study sought: (1) to investigate the potential impact of human visitors on Australian sea lions hauled out on Carnac Island, (2) to consider implications of the results for the management of Carnac Island Nature Reserve, and (3) to examine under which conditions tourism and recreation around sea lions can be sustained in the long term.
Sea lion numbers, rate of return to the site, behavioural response to human presence and incidents of disturbances of sea lions by visitors were recorded over a period of four months on Carnac Island. A survey of 207 visitors was also carried out.
Findings indicated that there were two main types of human impacts on the sea lions:
A specific state of sea lion vigilance induced by low level, but ongoing, repetitive disturbances from human presence, sustained at various approach distances ranging to more than 15 m, vigilance that is different from the behaviour profile observed in the absence of human disturbance,
Impacts resulting from incidental direct disturbances of sea lions by visitors from inappropriate human recreational activities or from visitors trying to elicit a more active sea lion response than the usual sleeping or resting behaviour on display; these impacts included sea lions retreating and leaving the beach, or displaying aggressive behaviour.
Impacts on sea lions from these disturbances may range from a potential sea lion physiological stress response to sea lions leaving the beach, a reduction in the time sea lions spend hauling out, and, in the longer term, the risk of sea lions abandoning the site altogether. Repeated instances of visitors (including unsupervised young children) approaching sea lions at very short distances of less than 2.5 m represented a public safety risk.
Results also indicated that (1) the numbers of sea lions hauled out and their rate of return to the beach did not appear to be affected by an increase in the level of human visitation (although longer-term studies would be required to confirm this result); and (2) there appeared to be a high turnover rate of sea lions at the site from day to day, suggesting that there are frequent arrivals and departures of sea lions to and from Carnac Island.
The visitor survey indicated that many visitors to Carnac Island had a recreational focus that was not primarily directed towards sea lion viewing (incidental ecotourists). Although many visitors witnessed incidental disturbance caused by humans to sea lions, they did not seem to recognise that they themselves could disturb sea lions through their mere presence. Visitors also seemed to have a limited awareness of the safety risk posed by sea lions at close range. Visitors expressed support for the presence of a volunteer ranger on the beach and for more on-site information about sea lions. Finally, visitors indicated that they greatly valued their sea lion viewing experience. It is anticipated that the continued increase in visitation to Carnac Island from recreation and from tourism will result in intensified competition for space between humans and sea lions. Long-term impacts of human disturbances on sea lions are unknown, but a physiological stress response and/or the abandonment of haulout sites has been observed in other pinniped species.
The findings of this study highlight the need to implement a long-term strategy to reduce disturbance levels of sea lions by visitors at Carnac Island to ensure that tourism and recreation around sea lions can be sustained in the long term. Recommendations include measures to control visitor numbers on the island through an equitable allocation system between various user groups, the development of on-site sea lion interpretation and a public education and awareness program, the setting up of a Sea Lion Sanctuary Zone on the main beach, ongoing monitoring of sea lion and visitor numbers and other data, and a system of training and accreditation of guides employed by tour operators.
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