Oyster reef habitats have declined from historic levels due to a variety of reasons, including overharvest, disease, and degraded water quality. The harvesting of oysters has led to a loss of reef habitat for both oysters and reef-associated fauna. When oysters spawn, the larval oysters, or spat, depend on hard substrate for settlement and growth. Oyster shell is the preferred substrate for use in restoration because it most closely matches natural reef habitat, but it is often expensive and in limited supply. This study incorporated field and laboratory experiments to assess the relative habitat value of alternative substrates (crushed concrete, porcelain, crushed limestone, and river rock, as well as oyster shell) for larval oyster recruitment as well as reef resident fishes and macro-invertebrates. Replicate trays of each substrate type were deployed in St. Charles Bay, TX for four months during spring and summer 2012 and assessed for oyster recruitment and faunal diversity and density. Concrete, river rock, limestone and porcelain had similar spat recruitment densities compared to oyster shell (1300-2300 spat). Spat shell heights were also larger on these substrates (13-16 mm), while spat on porcelain substrates were slightly smaller (10-13 mm). All substrates except bare sediment had similar fauna species densities (200-500 individuals m-2). Limestone had lower fauna diversity (H’; 0-1) than concrete and shell (1-2). Laboratory experiments compared the effectiveness of these substrates in providing prey refuge from pinfish and blue crab predators. All substrates performed similarly resulting in very low (<20 %) prey mortality rates for either predator. Results may enable future restoration plans to be implemented at a lower cost while providing similar habitat functions.

This study examined whether movements of fishes across reserve boundaries reduced the difference in density and size of fish between reserve and non-reserve areas. Visual censuses, experimental trapping, habitat measurements and tagging were performed at 10 sites on two nearly contiguous fringing coral reefs at the northern edge of the Barbados Marine Reserve and at 10 sites on the two fringing reefs closest to the boundary in the non-reserve. The visual censuses showed that overall density and size of fishes large enough to be caught in Antillean fish traps were higher on reserve reefs than on non-reserve reefs. The differences in density and size varied considerably among species and were not statistically significant for individual species. In contrast to a previous study, experimental trap catches were not higher in the reserve than in the non-reserve. Visual censuses, trap catches, and their ratio (trappability) were affected by habitat variables. Species mobility, estimated by the maximum distance between locations at which an individual was captured, corrected for the sampling effort at that distance, was highly variable among species (medians 0--116m). For the more mobile species, movements within fringing reefs and between the nearly contiguous reserve reefs was high but extremely rare among reefs separated by expanses of sand and rubble. For this discrete fringing reef system, there is no evidence that movement across the reserve boundary influences the relative density or size of fish between the reserve and non-reserve.

Differences in coral reef fish assemblages were investigated on six South African and one southern Mozambican reef under varying management regimes. All of the South African reefs fall within marine protected areas (MPA) but are zoned for differing types and intensities of human activity. Reefs where no human activities are allowed were termed Sanctuaries, while those on which restricted fishing and SCUBA diving are permitted were termed Protected. The reef in southern Mozambique is subjected to unrestricted fishing and SCUBA diving and was consequently termed Open. This study consists of two parts. The first dealt with a community assessment which investigated and provided baseline data on the trophic structure, density, and species diversity of fish assemblages on each of the seven study reefs. The objective was to compare the aforementioned metrics between reefs and thereafter compare them between the different protection zones. The second part of this study focused on assessing the impacts of human activities using 25 fish indicator species. These species were selected a priori based on their ecological importance and sensitivity to human activity (fishing and diving). The selection process was then guided by the results of the community assessment. The objective was to use these species as indicators of recreational diving and fishing pressure in the different protection zones. Density, biomass and size frequency analyses comprised the primary metrics in this assessment. Randomly stratified underwater visual censuses (UVC) were used to collect the fish data and these were conducted on reefs inhabited by a coral community considered to be the core community on South Africa’s reefs in terms of biodiversity and coral cover. The fish community assessment consisted of timed counts in which all non-cryptic fish species were quantified. Indicator species counts employed the point count technique with a radius of 10 m. An average of 11 community counts and an average of 62 point counts were conducted per reef. Various environmental variables and habitat characteritics were recorded during the UVCs. Multivariate analysis of the fish assemblages indicated that the fish community structure differed significantly according to reef protection status. Sanctuary reefs were significantly different from the Open reef in Southern Mozambique. Mean fish abundance was highest on Sanctuary reefs and lowest on the Open reef. In terms of overall species diversity, a total of 284 species belonging to 50 families were recorded, this being comparable to other reefs in the WIO region. Six families contributed more than 50% towards the fish community composition: Labridae, Acanthuridae, Chaetodontidae, Lutjanidae, Pomacentridae and Serranidae. All predator categories were well represented on Sanctuary reefs, while top-level predators were scarce on the High-Diving and the Open reef. Generalised linear model (GLM) regression analysis indicated that human activities were significant variables in accounting for the variance in fish community structure. The total fish abundance and biomass of the selected indicator species were significantly higher in Sanctuary zones and lowest in the Open zone. In addition, Sanctuary zones were characterised by high numbers of large predators, while non-Sanctuary zones were characterised by higher abundances of prey species. Target species were also larger and more abundant in Sanctuary zones. The data revealed that recreational fishing and high diving intensity may be influencing the fish community structure on southern African coral reefs, which was confirmed by GLM regression analysis. Long-term monitoring of these fish communities is recommended to confirm the trends observed in this data set. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2010.

Coral reefs are being destroyed and degraded by natural and anthropogenic processes. Live corals are becoming increasingly popular as marine aquarium specimens, in both the commercial and private sectors, leading to the degradation of coral reefs. This often has serious economic implications for the fishing, aquarium and tourist industries. It is clear that there is a need for the management and protection of these fragile ecosystems. The artificial propagation of coral is desirable as it will alleviate the demand for wild coral specimens, and will also provide a stock for the rehabilitation of damaged reefs. Although corals are being propagated worldwide by hobbyists, reports on their work are mainly anecdotal and there is little in the scientific literature on the specific requirements for optimal growth rates and survival in suitable coral species. This study thus focused on developing techniques to propagate a range of appropriate coral species and to promote their optimal growth. The results revealed that different morphological groups of scleractinian corals require specialised techniques of fragmentation and attachment to ensure survival. The corals were broken using a hammer and chisel. Attachment techniques varied from the use of superglue (which is widely used in the United States), to thermoplastic glue. The mean mortality using superglue was 73% (n=120, ±0.167), using epoxy, 62% (n=120, ±0.127) and with thermoplastic glue it was 11% (n=120, ±0.108) Superglue was extremely difficult to work with and proved ineffective, especially when attempting to glue uneven surfaces. Certain species did not survive using this adhesive due to exposure of the coral to air. The most effective method of rapid attachment was the use of thermoplastic glue that set rapidly underwater. The use of electrolysis to promote the attachment of coral nubbins was tested as an alternative to the various adhesives. This method increased the survival of the nubbins and eliminated exposure to air. It has proven suitable for both coral propagation and in situ reef rehabilitation. Growth experiments revealed that the manipulation of current flow, light and the addition of different feeds had different effects on the growth rates of selected candidate species. A suite of optima was thus developed for each species. The majority of species grew best in a bi-directional current flow, with yeast as feed, under actinic blue light. An experiment that combined the optimal current flow, feed and light conditions, revealed that the majority of species grew best under mixed light with yeast as feed. The trade in corals is sensitive in terms of their handling, transportation and CITES (Convention on International Trade in Endangered Species) status. Having established the viability of their propagation, consideration was given to appropriate regulatory and marketing procedures to accommodate this sensitivity of the cultivated material. / Thesis (M.Sc.)-University of Natal, Durban, 2001.

The causes of increasing outbreaks of Acanthaster planci on the Great Barrier Reef have been a point of hot debate in recent years. It is unknown whether the increased success is due to nutrient runoff, salinity levels, or a decrease in predation, among other possibilities. In this paper I argue that the primary influence on outbreak status is sea surface temperature. From existing literature, I demonstrate that sea surface temperature in the Great Barrier Reef has increased by 0.4°C per year over the past three decades. I attempt to tie this increase with an increase in frequency of A. planci outbreaks on a selection of reefs throughout the Great Barrier Reef region. Due to the development of A. planci, specifically the fact that it takes them between 2 and 3 years to reach full maturity, I examined the potential relationship between an outbreak and the sea surface temperature 1 and 2 years before the event. Through my exploration of the data and my subsequent data analysis, it is clear that there are no statistically significant results when comparing the three classifications of outbreak (active, incipient, and recovering) and not outbreaking populations with temperature at each of the three time relationships. However, when I considered the three stages of outbreak to be “affected” and those not outbreaking to be “unaffected”, I found a statistically significant relationship. This finding has important implications when looking at the temperature changes that have been predicted for the Great Barrier Reef region due to global climate change. If the water temperature continues to increase, A. planci will more often be living within their optimal temperature range and will be more successful, continue to have major outbreaks that devastate the reef ecosystem, and eventually destroy it all together.

Artificial reefs are being built in most parts of the world for a wide variety of purposes. Divingtourism is a common motivator for the construction of many reefs, particularly in the tropics,although the most widely used purpose is to improve or reconstruct hard bottom habitats andincrease the yield from fisheries. There are two main reasons for why aquatic life is attracted toartificial reefs. They provide excellent protection by often being hollow or filled with crevicesand cavities and increasing opportunities for improved foraging through accumulating biomassand extending the foraging range of an organism by acting like stepping stones. Sweden is acoastal country with few artificial reefs. In this study, two reefs were constructed in the sea offthe coast of Halmstad, Sweden to test small scale artificial reef production, marine organismcolonisation of the reefs during the first year, and to increase the local marine life diversity.Many marine organisms that would not normally occur in the sites where the reefs wereconstructed were observed, such as Symphodus melops and Anguilla anguilla. The reefs alsoprovided a new “clean slate” substrate for the settling of sessile organisms such as Urticina felinaor partially sessile organisms (i.e. during a certain stage of their life-cycle) such as some speciesof Cnidaria polyps. The tested method to construct these reefs was relatively cost effective for itspurpose. However a few minor but vital improvements, such as better binding materials, areneeded. Local marine life in the area has become more diverse during the experiment and thatalone is enough reason to motivate construction of similar reefs along the Swedish coast. / Artificiella rev anläggs runt om i världen med en mängd olika syften. Det är vanligt att dykturism används som anledning för att bygga artificiella rev, speciellt i tropikerna. Restaurering av hårdbottenrev och mål att öka kommersiella fiskebestånd är dock de största motiveringarna. Det finns två huvudsakliga orsaker till varför akvatiskt liv attraheras av konstgjorda rev. De erbjuder utmärkt skydd i form av håligheter och sprickor, samt att de ökar möjligheterna för födosök genom att ackumulera biomassa och fungera som ”stepping stones”, det vill säga utöka födosökningsområdet. Sverige är ett kustland med få artificiella rev. Två rev anlades i Laholmsbukten, Kattegatt, just utanför Tjuvahålan i Halmstad med syftet att undersöka effektiviteten och nyttan av småskaliga rev, att studera marina organismers kolonisering av reven och att öka den lokala biodiversiteten. Många marina organismer som inte borde förkommit i området där reven anlagts tidigare observerades. Ett par exempel är Symphodus melops) och (Anguilla anguilla). Reven fungerade även som rena underlag för sessila organismer att fästa på. Djur som till exempel havsros (Urticina felina) och Cnidariapolyper noterades. Metoden för att konstruera reven visade sig vara kostnadseffektiv i förhållande till syftet, men några viktiga steg, bland annat fästmaterialet, behöver förbättras. Den lokala artmångfalden ökade efter anläggningen av reven och borde vara nog motivering för att fortsätta bygga liknande rev längs den svenska kusten.

In 2008 and 2010, exotic drift pumice was collected from a total of 40 beaches around the main island of New Caledonia, Southwest Pacific. This island is enclosed by a barrier reef lagoon whose 2008 designation as a UNESCO World Heritage Site brought attention to the ongoing environmental degradation caused by a century of open cast nickel mining. This type of mining is notorious for producing voluminous fine-grained waste sediment that clogs waterways and may compromise the biodiversity of the lagoon. This study examines the use of drift pumice as a visual marker of suspended sediment transported within and around the lagoon. The frequent, voluminous pumice eruptions in the region provide ample source material that is fairly durable and highly mobile in water. Geochemical analyses identified two recent eruptions in the central Tonga arc as the source of the pumice, which was transported to New Caledonia by the South Equatorial Current. Pumice abundance was shown to correspond directly with the incoming wave intensity. Coupling pumice distribution data with information about the beach morphology, it is possible to use land-based data collection methods to identify at-risk coastal areas exhibiting elevated fluvial input with reduced marine influence. / Methods -- Study area -- Regional setting -- Geomorphology -- Geochemistry -- Petrography -- Discussion. / Department of Geological Sciences

The Drakensberger is a medium-framed black cattle breed indigenous to South Africa. The breed is concentrated mainly in Mpumalanga, the Eastern Free State and Kwazulu Natal. The breed fares well in key requirements for successful cattle farming. The North West Province and Northern Free State are some of the major cattle producing areas in South Africa. The Drakensberger does not enjoy a large market share in the region, at around 5-10%. The reasons for this lack of popularity of the breed are not evident. The study aims to establish why the breed in the region does not have the market share it seemingly deserves. Farmers are resistant to farm with the breed despite its good qualities. A literature review was performed to gain background on the cattle industry. Some breeds, their attributes and reasons for being successful, were explored. The Drakensberger was researched in detail, examining the breed’s potential. From literature it was evident that the breed has no fatal flaws and even outperforms certain breeds in some aspects. The current positioning of the breed in the market was described. A questionnaire was designed in order to determine which cattle breeds respondents prefer, why they prefer these breeds, what the sentiment of respondents in the region is towards the Drakensberger and reasons for the sentiments. A sample was selected and the questionnaires were completed through personal interviews. The areas covered were in the North West and Northern Free State. From the responses it was established that almost 50% of respondents farm with Bonsmara and Simmentaler breeds. The Drakensberger did not feature highly. It was found that farmers prefer the breeds due to hardiness, fertility, weaning weight and the colour of the breed. The Drakensberger is not a very popular breed and not well known. The main reasons for farmers not choosing the breed are based on a lack of information, perceptions that the black breed is more sensitive towards heat and that farmers preferred cattle. Respondents indicated being somewhat aware of evidence dispelling perceptions around the breed and indicated that the research is valuable to an extent. It was concluded that the Drakensberger is not reaching its potential in the region due to the black colour of the breed and due to a lack of quality information of the breed. It is recommended that a focused information and promotion campaign be launched in order to improve the image of the breed and to increase market share. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.

The Drakensberger is a medium-framed black cattle breed indigenous to South Africa. The breed is concentrated mainly in Mpumalanga, the Eastern Free State and Kwazulu Natal. The breed fares well in key requirements for successful cattle farming. The North West Province and Northern Free State are some of the major cattle producing areas in South Africa. The Drakensberger does not enjoy a large market share in the region, at around 5-10%. The reasons for this lack of popularity of the breed are not evident. The study aims to establish why the breed in the region does not have the market share it seemingly deserves. Farmers are resistant to farm with the breed despite its good qualities. A literature review was performed to gain background on the cattle industry. Some breeds, their attributes and reasons for being successful, were explored. The Drakensberger was researched in detail, examining the breed’s potential. From literature it was evident that the breed has no fatal flaws and even outperforms certain breeds in some aspects. The current positioning of the breed in the market was described. A questionnaire was designed in order to determine which cattle breeds respondents prefer, why they prefer these breeds, what the sentiment of respondents in the region is towards the Drakensberger and reasons for the sentiments. A sample was selected and the questionnaires were completed through personal interviews. The areas covered were in the North West and Northern Free State. From the responses it was established that almost 50% of respondents farm with Bonsmara and Simmentaler breeds. The Drakensberger did not feature highly. It was found that farmers prefer the breeds due to hardiness, fertility, weaning weight and the colour of the breed. The Drakensberger is not a very popular breed and not well known. The main reasons for farmers not choosing the breed are based on a lack of information, perceptions that the black breed is more sensitive towards heat and that farmers preferred cattle. Respondents indicated being somewhat aware of evidence dispelling perceptions around the breed and indicated that the research is valuable to an extent. It was concluded that the Drakensberger is not reaching its potential in the region due to the black colour of the breed and due to a lack of quality information of the breed. It is recommended that a focused information and promotion campaign be launched in order to improve the image of the breed and to increase market share. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.

Koh Chang Marine National Park is a popular tourist destination located off the east coast of Thailand. Coral reefs are one of the park's main attractions, and thousands of visitors from around the globe enjoy the opportunity to snorkel or dive in the park's clear, warm waters. Rapid growth in Koh Chang's marine tourism industry over the last decade raises concerns about the ability of some reefs to sustain a healthy and attractive environment. Ecological and social impacts associated with increased levels of marine recreation can transform and even permanently destroy both the character of coral reef ecosystems and the quality of the recreation experience, ultimately resulting in declines in tourism demand. The broad objective of this study was to establish a baseline understanding of the social dimensions of the snorkeling industry in Koh Chang, Thailand, and to recommend a suite of management actions that will sustain economic benefits while still yielding the benefits of protecting aesthetic and biological values. The recreation carrying capacity, Recreation Opportunity Spectrum, and Limits of Acceptable Change concepts were used to guide and inform the research. Data were collected using three primary methods: participant observation, unstructured interviews, and structured questionnaires. Personal observations and unstructured interviews allowed for an assessment of the park's environmental, social, and managerial settings. The tour operator questionnaire was designed to measure the size and characteristics of the snorkeling industry, awareness of environmental impacts, and support for visitor management strategies. The questionnaire was completed by eight tour operators. The visitor survey was designed to gain an understanding of the demographics of snorkelers, satisfactions, knowledge and awareness, and crowding. The survey was completed by 716 snorkelers. Results of the visitor survey suggest that snorkelers have a similar demographic profile compared with reef visitors in other parts of the world. Features of the snorkeling trip that had the greatest potential to add to, or detract from visitor experiences were related to the quality of the natural environment, a finding that is consistent with other studies of snorkelers and divers in coral reef settings. The social conditions were rated among the least important influences on visitors' experiences, a somewhat surprising finding as the number of other people is an important indicator of quality of the visitor experience in terrestrial environments. Overall, visitors were generally satisfied with the physical, natural, and social conditions, but the degree of satisfaction varied among individual snorkeling trip features. The lowest levels of satisfaction were expressed for the social conditions and several features related to the quality and condition of the natural environment. Low levels of satisfaction were also expressed for a number of service features. Results from personal observations, unstructured interviews, and questionnaires suggest that the environmental impacts of use may be significant. On a daily basis, reefs were touched, abraded, kicked, and stepped on by snorkelers, and these inappropriate behaviours can cause considerable damage to benthic organisms and the aesthetic appeal of the reefs. Tour operators' perceptions of impact were close to those defined in the recreation ecology literature, but operators may not be aware of the impact of their own behaviour on the marine environment. Over half of visitors perceived the impact of snorkeling on the reef to be "large/very large", suggesting that visitors have some awareness of the environmental impacts of use. The social impacts of use were also significant, as over 90% of visitors reported feeling at least slightly crowded, and 20% felt extremely crowded. Study results also showed that snorkelers are not a homogenous group. Variability in visitor response was explained in part by the recreation specialization framework, and country of origin. Differences between visitors' level of commitment to snorkeling and the underwater world were apparent between specialists and generalists, and specialization helped explain variability in environmental preferences, sensitivity to environmental impact, knowledge and awareness, and sensitivity to crowding. Visitors with different cultural backgrounds also had significantly different participation characteristics, satisfaction levels, knowledge and awareness, and crowding perceptions. Snorkelers are not homogenous, but unfortunately, the recreation settings provided are. Results from personal observations and interviews suggest that tour operators provide a single, uniform type of snorkeling experience that can be characterized as undeveloped with low levels of regimentation and moderate to high levels of use. Given the variability in the visitor population, provision of a single recreation opportunity may leave many snorkelers less than fully satisfied. This study identified several imminent threats to the quality of the visitor experience, reef conservation, and the sustainable' of the snorkeling industry. Active visitor management planning and resource protection programmes are urgently needed to balance park uses with the capability of the reefs to sustain such use indefinitely. Recommendations that contribute to improved visitor management and reef conservation are provided.