Marine ecology topics

HO112 Tracking the recovery of a keystone urchin species and its role in reef restoration

(start dates 14 June, 21 June or 28 June; need to complete dive training and the Caribbean reef ecology course)

Under natural conditions, the sea urchin (Diadema antillarum) is the most important herbivore on Caribbean coral reefs, and is therefore considered a keystone species. However, a disease in the 1980s caused the death of an estimated 98% of individuals throughout the region. This mass mortality event had a devastating effect on reef health, driving subsequent phase shifts to algal dominated benthic communities. Recovery has been extremely limited, with populations on most reefs still severely depleted, and Utila Island is a classic example of this. Remarkably, the Banco Capiro reef system in Tela Bay has a population density of D. antillarum at astonishingly high levels. It also boasts extremely high benthic reef health, despite historical overfishing leading to a complete collapse of the fishery. Since its recent discovery, Operation Wallacea scientists began detailed population studies in 2013 and this project will continue to build on this. The primary objective is to quantify changes in the abundance, biomass and population structure of D. antillarum on the reefs of Utila and Banco Capiro. Further data will assess the potential roles of competition, predation and environmental factors in driving the recovery on Banco Capiro.

Extended Project Summary


HO113 Managing the Caribbean lionfish invasion

(start dates 14 June, 21 June or 28 June; need to complete dive training and the Caribbean reef ecology course)

This project has a waiting list

Lionfish are an invasive species in the Caribbean and are having a devastating impact on local fish communities throughout the region. Introduced in the 1980s, believed to be by accident, lionfish have spread extremely quickly and are now found as far as New York City and Brazil. Their success is down to a number of factors, including their high reproductive rate, generalism in terms of both diet and habitat, and a lack of natural predators. They are now considered to be one of the greatest threats to the future of Caribbean coral reefs and their fish communities. Management approaches to dealing with the lionfish invasion are limited, with one of the most common being direct removal via spear fishing. This relies on regular visitation to individual reef sites, as studies have shown full recovery of lionfish populations only five months after complete removal. Baseline data will be collected on population densities of lionfish at sites of varying intensities of culling. Lionfish will subsequently be removed and morphometric measurements taken along with dissections for physiological and gut content assessments, which can link fish assessments to gauge prey availability. In addition, lionfish behavioural responses to divers, such as Flight Initiation Distance (FID) and Alert Distance (AD) can be assessed, which could also be expanded to include commercially valuable fish such as grouper.

Extended Project Summary


HO114 Interactions between reef health and fish communities

(start dates 14 June, 21 June or 28 June; need to complete dive training and the Caribbean reef ecology course)

This project has a waiting list

The ecological and economic value of coral reef fish communities makes them vital not only to ecosystem health but also to local food security and livelihoods. However, as consumers they are ultimately dependent on the abundance and composition of primary producers within the system, but also the provision of microhabitats for shelter. Competition for space on Caribbean reefs is extremely intense, with traditionally dominant hard corals increasingly being replaced in recent decades, primarily by macroalgae, but also soft corals and sponges. These phase shifts have significant impacts on benthic structure and function, with knock-on effects on dependent communities such as fish. Students on this project will conduct fish surveys on a wide range of reefs in both Utila and Tela using cutting edge stereo-video technology, which allows not only abundance and diversity measurements, but also accurate biomass estimates from published species-specific length:weight relationships. These data will be compared to benthic assessments using line intercept video transects and state of the art 3D computer modelling, to investigate how benthic health and structure impacts fish communities at the species, family and feeding guild level. With over three years of data already available, students can also incorporate a temporal component to explore long-term trends in benthic and fish community composition at key study sites.

Extended Project Summary


HO115 The dynamics of mutualistic cleaning interactions on Caribbean coral reefs

(start dates 14 June, 21 June or 28 June; need to be dive trained and to have completed the Caribbean reef ecology course)

On coral reefs, the cleaning behaviour of certain species represents an important interspecific and mutualistic relationship that provides a vital ecological service to the wider reef fish community. In the Caribbean, cleaning is performed by both fish (primarily gobies of the genus Elacatinus) and invertebrates (primarily the Pederson cleaner shrimp, Ancylomenes pedersoni). Cleaner species occupy cleaning stations that are sought by client fish who perform set behaviours in order to initiate cleaning. The dynamics of these interactions are complex, and span the taxonomic spectrum of the reef fish community, with Pederson cleaner shrimp alone known to service over 20 families of fish. After mapping the cleaning stations present at a site, students will use remote video observations to explore patterns in cleaning behaviour involving shrimp, gobies or both. Projects could focus on drivers of clientele composition, or how cleaning frequency and duration varies between client species. Alternatively, projects could build on recent research demonstrating the impact of diver presence on the provision of cleaning behaviour through a combination of in water diver observations and remote videography.

Extended Project Summary


HO116 Coral reef 3D complexity as a driver of ecosystem function and biodiversity

(start dates 14 June, 21 June or 28 June; need to be dive trained and to have completed the Caribbean reef ecology course)

The structural complexity of an ecosystem is one of the primary drivers of biodiversity, and this is especially true for coral reefs. As ecosystem architects of tropical reefs, hard corals lay down structurally complex calcium carbonate skeletons, which in turn provide the range and quantity of microhabitats needed to support the staggering levels of reef biodiversity. However, recent decades have seen a significant loss of hard coral cover, particularly the more structurally complex branching growth forms, leading to a phenomenon known as reef flattening. The Caribbean has been particularly impacted, and the carrying capacity of associated fish and invertebrates has subsequently decreased. Students on this project will film areas of reef using GoPro cameras while diving, and use the footage to construct state of the art 3D computer models. These models are proportionally accurate and allow 3D complexity to be quantified like never before. Structural complexity measurements will then be linked to observational data of target species of fish and invertebrates to explore how 3D reef structure influences biodiversity and ecological processes.

Extended Project Summary


HO117 Designing an optimal monitoring strategy for Caribbean coral reefs using novel technological solutions

(start dates 14 June, 21 June or 28 June; need to be dive trained and to have completed the Caribbean reef ecology course)

Global coral reef research and management remains heavily reliant on basic in water data collection by divers and snorkellers. However, data quality can vary enormously due to factors such as level of training, in water ability and observer bias. With the emergence of affordable underwater photography and videography, a new suite of techniques has become available to marine researchers that not only increases accuracy of data, but allows new questions to be addressed that would otherwise be impossible through traditional methods. Coral reef health can now be assessed using video transects, while cutting edge stereo-video surveys allow fish communities to be accurately assessed not only for abundance and diversity, but also the much more useful metric: biomass. Even more excitingly, a new collaboration between Opwall and Oxford University has developed a method of constructing accurate 3D computer models of areas of reef filmed using GoPro cameras. These models allow quantification of structural complexity, and have the potential to replace traditional benthic transect techniques. Students on this project will spend time carrying out each of the methods described above, conducting a thorough assessment of their strengths and weaknesses, to design an optimal approach for Caribbean reef monitoring for the modern era.

Extended Project Summary


HO118 Physiology and behaviour of the long-spined sea urchin, a keystone Caribbean coral reef herbivore

(start dates 14 June, 21 June or 28 June; this project is predominantly laboratory-based but can also include a diving element; need to complete Caribbean reef ecology course and dive training if required)

This project has a waiting list

The long-spined sea urchin (Diadema antillarum), is responsible for the maintenance of coral reef health throughout the Caribbean. However, in the early 1980s a region wide epidemic reduced their populations by an average of 98%, which stimulated the widespread macroalgal phase-shifts that currently plague the Caribbean. Despite the fact that restoration of D. antillarum is widely believed to be a conservation priority we know surprisingly little about their physiology and behaviour. The aim of this project is therefore to explore the innate responses of this keystone species to numerous external environmental and physical factors, such as food and habitat availability, rising sea surface temperatures and ocean acidification, which may affect the success of targeted conservation efforts. These questions will be answered through a series of laboratory manipulations on urchin specimens collected from nearby reefs.

Extended Project Summary


HO119 The behaviour of invasive lionfish on Caribbean reefs

(start dates 14 June, 21 June or 28 June; this project is predominantly laboratory-based but can also include a diving element; need to complete Caribbean reef ecology course and dive training if required)

This project has a waiting list

The invasion of lionfish in the Caribbean has developed into one of the greatest threats to the survival of the region’s coral reefs thanks to the devastating effect they have on native fish populations. Research has naturally focused on mapping the spread of lionfish, quantifying their ecological impacts, and exploring management interventions to reduce their numbers. However, improving our understanding of the behaviour of this species on non-native reefs is of particular interest to better grasp the underlying success of their invasion. This project will assess lionfish behaviour both on the reefs and in a small laboratory, where individuals will be captured and processed. Particular focuses of this work could include prey selectivity, and habitat preferences to investigate the cryptic nature of this species, and data can be linked to ecological characteristics of the reef itself.

Extended Project Summary


HO120 Behaviour and feeding ecology of Caribbean reef herbivores

(start dates 14 June, 21 June or 28 June; need to be dive trained and to have completed the Caribbean reef ecology course)

Coral reefs are traditionally found in nutrient-poor (oligotrophic) water. Hard corals are very successful nutrient recyclers, which allows them to thrive in these conditions despite their extremely slow growth rates. Faster growing macroalgae are at a competitive disadvantage under these conditions, whilst any significant growth that does occur is kept in check by a large community of herbivorous fish and invertebrates. However, in recent decades organic pollution along tropical coastlines has caused widespread nutrient loading, while overfishing and other impacts has greatly reduced herbivore populations. As a result, macroalgae has begun to take over reefs in what is known as a phase shift, compromising the long-term health and resilience of these important ecosystems. This project aims to explore patterns in feeding behaviour and efficiency between different Caribbean herbivores, using a combination of in situ observations via scuba diving and remote videography. Data will focus on feeding preferences between different types and densities of macroalgae, and on calculating feeding rates using artificial algal plates placed on the reef. Students will also conduct surveys of the herbivore communities present to gauge overall grazing pressure at study sites.

Extended Project Summary


IN122 Functional ecology of coral reefs

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained if incorporating a diving element into the research)

Coral reefs exist within a dynamic equilibrium, their form and function being driven by environmental conditions and interactions between the species that inhabit them. Dominance of reef building corals is diminishing across the world, whilst other taxa such as algae start to dominate. The shift from coral to algal dominance has been well documented in the Caribbean and appears common place. However, within the mega biodiverse reefs of the Wakatobi there has been no such shift. One hypothesis is that the levels of algal removal by herbivorous fish species reduce the competitive ability of algae preventing a regime change. However, as many species of larger fish herbivores are exploited it is possible that algae will increase in abundance, start to dominate benthic systems and bring about a decrease in reef biodiversity. There is thus an urgent need to quantify the amount of herbivory and to explore the relationship between herbivore biomass, rates of herbivory and habitat quality. Levels of herbivory can be estimated through examination of the biomass of herbivores present on reefs coupled with studies of feeding behaviour. It remains unknown whether different fish species exploit the same algal species and therefore it is quite possible that it is the assemblage of herbivores present that is key rather than the overall biomass of this functional group combined. Dissertations working in this area will help managers to identify the key species and critical biomass of herbivores needed to ensure reef building corals remain competitive and continue to underpin the extreme globally important biodiversity of reefs within the coral triangle.

Extended Project Summary


IN123 Biological agents of reef mortality

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained if incorporating a diving element into the research)

Reef building corals are the key ecosystem architects that produce the complex physical structure that provides habitat for the many thousands of species inhabiting reefs. Numerous different species of animals, algae and microbes threaten reef building coral species. The extent of this threat is largely dictated by environmental conditions. In a healthy reef system agents causing mortality and the loss of coral cover is outweighed by the recruitment of new corals and the growth of existing colonies. However, in many reef systems environmental quality is decreasing, resulting in corals being put under increasing negative pressure and the balance starting to tip in favour of coral loss. There is a continual need to examine the key causes of coral mortality on any reef and particularly following increased environmental stress such as those caused by the 2016 global thermal anomaly. Research is required to determine the extent of threat caused by different agents of coral mortality such as corallivorous fish and invertebrates, bio-eroders, actively competing benthic taxa as well as increased microbial activity resulting in coral disease. Research obtained needs to be compared between different sites and reef zones in conjunction with full environmental and biological characterisation to determine which species of coral and which systems are most greatly threatened, and what management is needed to reduce coral loss and increase coral growth.

Extended Project Summary

IN124 Coral reefs and environmental change

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained if incorporating a diving element into the research)

This project has a waiting list

The implications of short and long-term environmental change have been widely discussed in the scientific literature and media. The sensitivity of reef building corals to environmental conditions varies greatly between species. It now appears that the most sensitive species tend to have a branching or tabulate growth form. Such species, most often belonging to the genus Acropora, greatly add to the physical complexity of the reef scape. Their loss from the system will reduce physical rugosity and most likely biological diversity, and the implications of this loss needs to be carefully considered. The 2016 thermal anomaly had a limited impact on reefs of the Wakatobi as compared to other regions, although the impact was greatest on branching and tabulate corals particularly in shallow waters. This leads to worrying uncertainty over whether fish species formally associated with these growth forms are still abundant or whether they have also been lost from the system. The ecological consequences of the loss of these fish depends on the species in question and their larger role in the ecology of these reefs. Research is required that examines the relationship between branching and tabulate corals, and the degree of fidelity that exists between these habitat types, resident fish species and the sensitive coral growth forms. Dissertations in this field could also focus on the abundance of branching and tabulate corals across reef sites and reef zones to determine the actual impact of the 2016 bleaching event on the reefs of the Wakatobi.

Extended Project Summary


IN125 Behavioural adaptations of dwarf cuttlefish, Septa bandensis

(start dates 20 June, 27 June or 04 July)

As a group, cephalopods display a high level of nervous integration resulting in complex behavioural responses and social interactions that rival those seen in higher vertebrates. The Wakatobi National Park is home to at least 30 cephalopod species, many of which can be found inhabiting reef and reef-associated habitats. The dwarf cuttlefish (Sepia bandensis) is the most abundant cephalopod species found in the park, occurring in large numbers near rocky shorelines, on coral rubble, in seagrass meadows and at mangrove margins. While the species has some minor commercial value in local artisanal markets, its major importance lies in their ability to shape habitat ecology by indiscriminately preying on large numbers of small to medium sized crustaceans. In spite of their ecological importance, little is known about the feeding behaviour or social interactions in this species. The primary objective of dissertation projects could include aspects of feeding behaviour, effects of competition, and social interactions between individuals of different gender and/or size. Other studies may be considered but require approval of the field supervisor. All studies would be conducted using captive animals housed in the Hoga Island Research Laboratory and proposed studies must be non-lethal. Students must also check with their university advisor regarding their universities policies and procedures for working with cephalopod animals. Students are strongly encouraged to contact their project field supervisor early in the proposal development process.

Extended Project Summary


IN126 Are mutualistic relationships the norm?

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained if incorporating a diving element into the research)

This project has a waiting list

An evolutionary strategy for many species existing within mega biodiversity hotspots such as those of the coral triangle is to form mutualistic relationships with other species. Mutualistic relationships appear common and many examples have been well defined. Perhaps the clearest example of these are those that exists between anemones and their inhabiting anemonefish species and also the relationship between many species of fish and their cleaners such as the bluestreaked cleaner fish common to the Indo-Pacific. However, many other examples exist but have yet to be fully explored. Tight associations between species appear common place and inter-dependency between species is one of the main reasons relatively small areas can harbour such high levels of species richness. This research will explore the relationships between previously underexplored species by describing the interactions between different fish species inhabiting set areas of reef. For example several species of wrasse can be found to be associated with species of goatfish that feed within sandy sediments and the trumpetfish, especially at the juvenile stage, is often seen associated with other elongated fish where they seek refuge. This research is designed to highlight the commonality of mutualistic relationships and fish species interactions on reefs of different biological complexity. Research could also consider the implications of certain species loss and the interaction such loss has on ecological function.

Extended Project Summary


IN127 Seagrass and patch reef cology

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course)

Tropical seagrass beds are extremely important and provide numerous ecosystem and ecological services. The Wakatobi harbours some of the most biodiverse seagrass beds in the world. Seagrass habitat has been shown to provide refuge and nursery grounds for many economically important invertebrates as well as for fish, with some species being seagrass specialists whilst others migrate from the reef into seagrass beds daily or at specific points in their life cycle (ontogenetic migration). However, like many other important habitats in the world, seagrasses of the Wakatobi are threatened by numerous anthropogenic activities including fin-fisheries and invertebrate over exploitation, trampling, and by the presence of intertidal seaweed farms. The implications of these activities in isolation and when combined have not been fully explored or quantified in terms of their ecological or economic costs. Research is required that examines the implications of these activities for seagrass productivity, biomass and biodiversity and resulting consequences for permanent as well as transient invertebrates and fish that depend on the system for food or refuge. Seagrasses within the Wakatobi extend from the low tide mark through to the reef flat. This transition zone is characterised by intermittent coral patch reefs. The ecological significance of these coral patches, not only in terms of total biodiversity but also through the provision of nursery areas and transient “stop-over” sites utilised by fish migrating from reef to seagrass, has not been fully explored. Therefore within this research topic the ecological services of shallow subtidal patch reefs could be explored and questions investigated regarding their conservation value.

Extended Project Summary


IN128 Coral reef transitions: understanding regime shifts from coral to sponge-dominated states

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained if incorporating a diving element into the research)

There are reports from across the world of coral regime shifts, whereby declines in coral result in increased abundance of other benthic groups. Throughout the Caribbean these changes are typically to reefs dominated by algae, but in the Indo-Pacific changes to reefs dominated by other animal groups are more common. In the last few years there has been particular interest in the sponges as these are one group of organisms that have been identified as potential ‘winners’ in the face of environmental degradation and climate change. Within the Wakatobi a transition has occurred on one major reef system, Sampela, where coral abundance has declined over the last 10 years to very low levels, but sponge abundance appears to be increasing. In particular, this site is dominated by the giant barrel sponge Xestospongia spp. and the encrusting sponge Lamellodysidea herbacea; these have also been reported as increasing in abundance in other parts of the Indo-Pacific. In addition, recent experimental evidence has shown that sponges appear much more resilient to ocean warming and acidification than coral, so are likely to be a greater feature of coral reefs in the future. Dissertations in this area will build on long term data sets to track this shift in dominance and explore the ecosystem level effects. Projects might include examining population dynamics of key sponge taxa, exploring predator/prey interactions, competitive relationships and habitat use patterns as a result of the shift. In order to understand how reefs might function in the future there is urgent need to understand transitions to reefs that are no longer dominated by corals. Work in this area will contribute to understanding the ecosystem functions that might be expected from sponge dominated reefs, and also allow us to explore potential management interventions to prevent future regime shifts and restore existing sponge dominated reefs.

Extended Project Summary


IN129 Evaluating potential effects of rising environmental temperatures on thermal ecology of fiddler crabs, Uca spp. 

(start dates 20 June, 27 June or 04 July)

Often exhibiting high levels of biodiversity and endemism, mangrove forests demonstrate a remarkable interdependence between local flora and fauna such that a loss of diversity or density in one group has marked adverse effects on the other. Declines in burrowing crustacean populations, for example, have been shown to result in reduced organic turnover, decreased nutrient and energy cycling, and diminished primary productivity in mangrove species. Fiddler crabs (Uca species) are one of several semi-terrestrial, burrowing, mangrove decapods making up a keystone group commonly referred to as engineers. Indonesia boasts the highest diversity of fiddler crab species of any country in the world with 14 total species, seven of which can be found within an area of 4-square meters within the Ambeua Mangrove near Hoga Island. Previous research at the Hoga Marine Laboratory has shown that local fiddler crab populations are relatively tolerant of high temperatures; however, with environmental temperatures across the Malay Archipelago expected to increase by up to 4°C in coming decades, it is unclear how fiddler crab populations and ultimately mangrove ecosystems, may be affected. Potential dissertation projects could evaluate differences in thermal adaptations of Uca spp. occupying different intertidal regions, or may look at acclimation responses of a single Uca species. All studies would include a field observation component, though most of the empirical work would take place in the Hoga Island Research Laboratory. Students are strongly encouraged to contact their project field supervisor early in the proposal development process.

Extended Project Summary


IN130 Long-term changes in the community ecology of coral reefs

(start dates 20 June, 27 June or 04 July; need to have completed reef survey techniques course and be dive trained)

This project has a waiting list

The global demise of coral reefs has been well documented in the scientific literature. The reefs of the Wakatobi have been assessed by Operation Wallacea for the past 15 years. The abundance of reef building corals has declined but other functional benthic taxa, such as soft corals, have increased. As well as an overall decrease in reef building corals, the types of corals present, both in terms of species and colony structure have also changed. Where once reefs in the region harboured a mix of different colony growth forms (including branching, table, and foliose corals), the system today is dominated by massive (boulder-like) and encrusting corals. The physical form of the reef is therefore changing which has implications for resident and transient fish communities. During 2017 the research teams would like to complete the monitoring of reefs around the Wakatobi and use previous data combined with the final year of data collection, to determine how fish communities respond to changes in biological and physical structure of reefs. The detailed data set across six sites and three reef zones will allow managers to identify the likely consequences of long term changes in habitat quality for both biodiversity and food productivity. The relationship between benthic structure and fish community is a complex one but if habitats are to be actively restored we need to know how the fish community is likely to respond. Projects here could focus on the system as a whole, or could identify particular fish taxa that have changed and examine their interaction with specific reef structures across different spatial scales. For example we would predict that larger predatory fish respond to complex reef structures over larger spatial scales than smaller residential fish but that complexity of habitat may be needed at every spatial scale to support a healthy, biodiverse and productive fish community. Projects could therefore utilise a large historical data set, further assessment of varied reef sites and could include taxa specific assessment utilising behavioural studies. Data collected will be used to define future protective and active management intervention.


IN173 Fisheries research in local communities

(start dates 13 June or 27 June)

Opwall have been working with local fishing communities in the Wakatobi for almost 20 years, developing a deep understanding of the conservation issues associated with declining fish stocks and producing several award winning dissertations along the way. Opportunities exist for students to build on this extensive experience by completing dissertation projects focusing on artisanal fishing pressure by working alongside Opwall staff and local Indonesian partners in small fishing communities on and around Kaledupa island. To talk about this opportunity, and how it might be suitable for your undergraduate or masters dissertation research, please email Dr Dan Exton: dan.exton@opwall.com


ME149 A comparison of pristine and degraded mangroves in Akumal and theimpact of mangrove degradation on adjacent seagrasses and coral reefs

(start dates 12 June or 26 June)

This project has a waiting list

Mangrove forests are highly productive marine ecosystems that are essential for the health of adjacent ecosystems e.g. sea grass beds and coral reefs. Yet, as much as 1 – 2% of the global mangrove forests are lost per year. Mangroves draw down atmospheric CO2 sequester and trap fine sediments, facilitate vital biodiversity mechanisms (e.g. fish nurseries) and improve fishery productivity. Despite the obvious importance of mangroves, mangrove forests in the Yucatan Peninsula have been under considerable anthropogenic impact from harvesting, causing a reduction in important habitat and biodiversity, carbon sequestration, and the productivity of adjacent sea grass and coral reef ecosystems. If the ecosystem services that mangroves provide can be quantified, then there is scope to develop a mangrove equivalent of the REDD programme in which fishing communities could receive economic investment in exchange for continued protection of the mangroves. Projects could therefore focus on a comparison of the structure, function, and faunal diversity of pristine and degraded mangroves, or an investigation of wood degradation processes across mangroves of differing quality. In addition, projects could investigate health and diversity of seagrasses and coral reefs in relation to the level of degradation of adjacent mangroves. Belt transects and permanent plots will be used to record tree composition, basal areas and tree densities. Biodiversity assessments will be conducted by investigation of the available mangrove substrata. Snorkel and dive based transect and quadrat surveys may be used to assess diversity and coverage of seagrasses, hard corals and algae.

Extended Project Summary


ME150 Understanding the non-conventional cenote-mangrove forest system

(start dates 12 June or 26 June)

The Yucatan Peninsula is formed of limestone karst substrate that was once coral reef. As limestone is porous, rainwater seeps through the rock surface to form an extensive network of underground rivers accessed from the surface by sink holes, known locally as cenotes. Mangrove forests associated with cenotes in coastal regions are not new, but research of them is. This novel project aims to investigate the driving forces behind the structure and function of these unusual mangrove ecosystems and to investigate differences of animal community structure in comparison with coastal mangrove forests. The majority of mangrove animals exploit the available hard substrata within mangrove ecosystems. Areas such as mangrove prop roots and in particular large wood detritus (LWD) are favourable for most mangrove fauna, but nothing is known about the organisms that process the fixed carbon in cenote mangrove forests. Projects may highlight new and unreported information from forest structure and function, to mangrove fauna diversity and niche separation. Continuous belt transects and plots will be used to establish the tree structure, composition and basal areas with the cenote mangrove forests. Biodiversity assessments of the fauna upon mangrove roots, substratum and LWD will be made, and animal observations will be employed. Degradation processes of LWD will be recorded in the forests and compared with those from conventional mangrove forests.

Extended Project Summary


ME151 The conservation of and improvement of Caribbean coral reefs: Reef restoration through plantation of Acropora cervicornis

(start dates 12 June or 26 June)

This project has a waiting list

Acropora is one of the most important Caribbean corals in terms of its contribution to reef growth and fishery habitat. Acroporid species are the Caribbean’s fastest growing reef-building corals. Since the 1970s, Caribbean acroporid populations have been decimated by disease outbreak. Their recovery has been impaired by the general poor health of Caribbean coastal ecosystems. In Akumal this decline is estimated at >90%, although it is unlikely that this truly represents the loss of coral due to the lack of reliable data. Coral restoration is increasingly considered to be a viable recovery plan. In Akumal preliminary research has been conducted to trial success rates of coral nurseries where Acropora cervicornis is grown, propagated and then transplanted onto the reef. The methods used are minimally invasive and require cheap materials. The trials have proved to be successful, with doubling of live tissue from dying rescued fragments within one year, combined with successful fusion and growth of transplanted colonies onto the reef. In order to measure the impact of coral restoration work, it is essential to develop baseline data from which to measure the successful colonies that have grown as a result of the restoration work. Using continuous belt transects on the reef, the mapping of acroporid colonies will be conducted to assess the distribution, abundance and surface area of the colonies. Coral frags will be out-planted at various distances from the mother colony to measure successful recruitment and growth at different sites from that of the mother colony. Reef fish assemblages, particularly juveniles, will be assessed on reefs with none or few acroporid colonies. Established acroporid frags will then be planted onto those reefs and re-assessed. These data will be compared to reefs with a high density of acroprids.

Extended Project Summary