Honduras marine dissertation/thesis topics

The following topics are either based at the Utila marine research centre (HU projects) which is equipped to enable environmental processes to be researched and monitored. Other projects are based at the Cayo Menor research centre (HC) or can be done on Utila, Cayo Menor and Rio Esteban as comparison studies between one, two or all three of the Honduran Marine sites (HB). The islands of the Cayos Cochinos and Utila are home to a huge array of terrestrial habitats and species. Several of the species are only found on the islands and many more are still completely unstudied or remain undiscovered. Two of the projects are based at the marine research stations but study the terrestrial species on the islands.

HC221 Queen Conch distribution and ecology around the Cayos Cochinos (Weeks 5 -10; Training - need to have completed the reef ecology course HU008 or HC009 and be dive trained)

The Queen Conch plays a highly important role in the ecology and economics of the reefs around the Caribbean and the Cayos Cochinos islands. However, conch are a valuable food product and over-fishing in previous years has severely reduced the populations on the reefs and seagrass beds of the Cayos. The MPA around the islands is designed to prevent the extraction of conch by fishermen and allow the conch population to recover. This project will continue an ongoing monitoring and tagging program studying the population, growth and movement of Queen conch within the MPA from a series of sites that have been surveyed in previous years. Surveys would use the transect surveys to record conch populations, including re-measuring tagged conch from previous years and tagging and measuring new individuals. Data will assess the size class distribution of the species and quantify their recovery within the area. Projects can include more detailed behavioural and movement research by recording positional data of individual conch on a daily basis in a defined study area or look at habitat preference by doing surveys of the locations in which conch are common. The project could also identify potential levels of sustainable fishing for this species once the population has recovered and how it could be regulated to benefit the local fishing communities.

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HC222 Sea urchin population and ecology around the Cayos Cochinos (Weeks 5 -10; Training - need to have completed the reef ecology course HU008 or HC009)

Sea Urchins are a vital part of the ecology of Caribbean reefs where they act as one of the main herbivores of benthic algae and help prevent algal density increasing to levels where it can dominate and threaten the coral coverage of the reefs. However, in 1983 an unidentified disease decimated urchin numbers in the Caribbean, with up to 99% mortality in some areas. Urchins are long lived and slow growing so recovery is slow. To ensure the recovery of urchin populations their distribution, population and position within the reef ecosystem needs to be researched. Projects survey urchin populations on the reefs of the Cayos Cochinos, the data from which will be used as part of a long term dataset on urchin density. Data from previous years will be made available so temporal patterns in distribution can be assessed. While additional elements of urchin ecology can be studied including their habitat preference, relationship to other herbivorous species on the reef and the amount of algal coverage in relation to urchin densities. This project is snorkelling based and does not require dive qualification.

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HB223 Influences on reef fish populations on contrasting reef systems (Weeks 2 - 5, Utila; weeks 6 - 7, Rio Esteban and weeks 8 - 10 Cayos Cochinos; Training - need to have completed the reef ecology course HU008 or HC009 and be dive trained)

 The reefs around the Cayos Cochinos, Utila and Rio Esteban offer a unique opportunity to study the variety of influences on fish community status. Reef fish populations are subjected to a huge variety of different pressures and variables, both natural and human that dictates their abundance and diversity and many of these variables are little understood. Specific influences that are particularly important in Honduras are those of fishing, coral/algal coverage on reefs and the role of mangrove systems as nursery grounds for juvenile reef fish species. Over fishing has become a significant issue in the area and of particular importance to the artisanal fisheries in the area. Development has led to pollution and disturbance, causing changes in the levels of coral and algal coverage while mangroves are being destroyed to allow coastal development. Fishing on the Cayos Cochinos is prohibited because of the MPA, but is widespread around Utila. Utila has extensive mangrove systems whereas the Cayos Cochinos has none. Rio Esteban is a coastal system rather than an island so has reefs that are subjected to high levels of disturbance. Projects can be designed to study fish species, families or communities on the reefs around one, two or all three of the sites. Conclusions from the projects may identify the importance of the MPA around the Cayos Cochinos or the mangrove nursery grounds on Utila, while links between reef status and fish populations can be addressed across the range of reefs surveyed. Results from all projects can be used to suggest suitable conservation measures around the sites. The data gathered from the stereo video system and the photoquadrats on the various reefs around Utila, Rio Esteban and Cayos Cochinos will be used for these studies and students developing research questions around this topic will have access to the full data sets from all the reefs.

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HB224 Factors influencing small scale competition between corals, sponges and algae on the reefs of Utila, Cayos Cochinos and Rio Esteban (Weeks 2 - 5, Utila; weeks 6 - 7, Rio Esteban and weeks 8 - 10 Cayos Cochinos; Training - need to have completed the reef ecology course HU008 or HC009 and be dive trained)

Corals compete with algae, sponges and other invertebrates for space on the reefs. This topic could map small patches and outcrops of reefs around Utila, the Cayos Cochinos Islands and Rio Esteban and determine the percentage cover and interaction between the various competing organisms. Additional areas of potential research could be based on variables that may influence the balance between competing organisms. These can include biotic variables such as abundance of herbivorous species of fish and invertebrates such as surgeon and parrotfish or urchins that favour coral growth, or damsel fish abundances which "farm" the algae, favouring algal growth. Equally abiotic variables can include; nutrient and sediment conditions in the water, with high nutrients favouring algal growth, and suspended sediments decreasing light penetration, inhibiting both corals and algae. Corals may also be smothered by excess sediment and coral disease may be promoted by high nutrients and sediment. Measurements of coverage will be taken from digital photographs, others e.g. fish abundances will be measured in situ. Correlations can be made at each site between coral and algal abundance and diversity with the biotic and abiotic variables. The sites selected on this project will be studied in future years as part of a monitoring program of growth, recruitment and disease progression of individual corals.

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Utila is surrounded by seagrass beds, but these beds are subjected to a variety of disturbance and pollution from the developing town. Assessing the health of the seagrass beds and their associated macrofauna is vitally important to their survival. Projects will use diving and snorkelling to assess aspects of the health and ecology of the seagrass beds. The undisturbed sea grass beds of Cayos Cochinos provide an excellent comparative site with their pristine seagrass beds. Elements of study can include quantifying macrofauna and algae distribution within the beds and studying the relation this has to environmental variables including indicators of pollution and disturbance. The results of the study will be used to form part of a long term monitoring program of seagrass status around Utila and Cayos Cochinos MPA. Note this project can be done by snorkelling only.

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HU226 Small scale patterns of sedimentation rate on coral reefs (Weeks 2 - 8; Training - need to have completed the reef ecology course HC008 or HU009 and be dive trained)

One of the major stressors on corals is the settlement of suspended sediment on their surfaces. This leads to blocking of light, smothering of the coral mucus surface and increased risk of disease. For this reason sedimentation rate on a reef is considered as highly important in studies of coral reefs, especially with the ever increasing levels of suspended sediment in the marine environment resulting from large and small scale development and deforestation in coastal habitats. Large, generalised patterns of sedimentation are well understood, however there is little work studying sedimentation patterns within a single reef. The reefs outside the Coral View Research Centre have a natural gradient of sedimentation from the mouth of a local lagoon. Projects can be designed to use a large number of sediment traps on the reef to study patterns of sedimentation. These can then be linked to the topography of the reef, individual corals, benthic structures, sea fans and water currents. The results can be related to the distribution of corals on the reef to assess how important small scale sedimentation patterns are in influencing coral recruitment and distribution.

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HU227 Assessing the impact of mangrove degradation on their functionality (Weeks 2 - 8; Training - need to have completed the reef ecology course HC008 or HU009)

The island of Utila is dominated by mangrove and wetland systems. These are highly important to the functioning of the entire marine ecosystem on the island through their role in coastal protection and as fish nurseries.. However they are being placed under increasing threat from the development on the island, either through direct removal to clear space for construction, or more commonly through partial disturbance and pollution. Many previous studies on mangroves have compared the functioning of healthy systems to areas where mangroves have been completely removed, but little has been done on the impacts of degradation on mangrove systems and its effect on their functioning. This topic allows research to be done on mangroves in four contrasting lagoons. Of these lagoons one is subjected to high levels of organic pollution, while a second is subjected to physical disturbance from dredging and boat traffic, a third contrasting lagoon is relatively untouched and a fourth is part of a marine reserve. These contrasting systems provide an excellent opportunity to study the effects of differing levels of mangrove disturbance on sediment stability using cores and a muffle furnace to determine bulk densities of sediment. Another option is to compare the epibiont fauna of the mangrove roots to see if these correlate with levels of organic pollution. Estimates of the health of the mangroves can be made from the percentage of shoots that reach the sediment and the abundance and size of leaves on sample branches. This project is ideal for students studying environmental degrees and projects can analyse a variety of environmental measurements and potentially present the data through GIS. However, this topic can also be developed as a biological study by assessing the impact of mangrove degradation on their value as a fish nursery using trapping. On this topic students will be kayaking around the remote mangrove lagoons, exploring and surveying areas of Utila that are rarely if ever seen by other people.

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HC228 Cayos Cochinos Boa Constrictor or Ctenosaur ecology (Weeks 5-10)

This topic can focus on the general ecology of the endemic pink boa including spatial ecology, behavioural ecology, population size estimation, and dietary analysis or on the distribution, population size and morphological diversity of Ctenosaura melanosterna using a pole and noose to sample the population. Daily boa visual encounter surveys are conducted across the island and boas are captured by hand. Snakes are measured, fitted with a passive integrated transponder (PIT tag) for permanent identification, and released. Additionally some boas have radio-transmitters surgically implanted so that their precise positions can be determined for up to 3 years after release. Efforts will be split evenly each day between capturing and radio-tracking snakes. Possible dissertation projects could include determining activity ranges (radio-telemetry), population sizes and mortality rates, sexual dimorphism in head shape, and proximal influences on colour and colour change in boas. Cayo Menor is also the site of a long term study of the ctenosaurs where a large percentage of the population has been captured and marked with PIT tags and each animal has had a painted number on the side. The study has been ongoing for 3 years and short biographies of many of the animals are known (changes in home range, associations with other animals etc). An interesting project would be taking tissue samples of many of the numbered animals and determining familial relationships from genetic analysis, compared to observational data on apparent relationships. The samples would need to be returned to the DNA lab in the Cusuco Park so that the samples could be processed and exported as FTA Whatman cards. Note students doing this topic would need funding to complete the sequencing of each of the samples(approx $6 per sample) back at their home institution. Other possible dissertation topics include the distribution, population size and morphological diversity of Ctenosaura melanosterna on Cayo Menor.

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HB229 The ecology and conservation of Anolis lizards in the Cayos Cochinos and Bay Islands (Weeks 1-5 Utila and weeks 5 - 10 Cayos Cochinos)

This topic centres on the thermal ecology of lizards in the genus Anolis from the Cayos Cochinos and Bay Islands of Honduras. Since the 1960s, temperatures have risen 2.5°C in the Caribbean, and recent evidence has emerged that suggests global warming will affect forest-dwelling lizards that occur in the tropics much more dramatically than it will lizards in other regions of the world. Because three species of forest-dwelling Anolis are endemic to the Bay Islands (two out of the three occur on Utila), it is valuable to understand their thermal biology in order to predict the effects that global warming will have on their survival. Data types that will be collected include: environmental temperature distributions (from copper plated models shaped like lizards), preferred temperatures of individuals, optimal temperatures for sprinting (involving chasing lizards along a race track), upper thermal tolerances, and internal body temperatures. Additional data types include body size, habitat use, and abundance. Data will be used to predict the effects of global warming on lizard communities as temperatures continue to rise in the Caribbean. Lizards will be captured in the field using small nooses attached to fishing poles. Many other potential projects are available studying other elements of Anolis ecology. Projects can be conducted in the Cayos Cochinos, on Utila, or both, and data collected on Roatan and Guanaja will also be available to students.

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HB230 Development of an aquaculture business within the Garifuna community to supply the aquarist trade (Weeks 3 - 5 Utila, weeks 6 - 7, Rio Esteban and week 8 Cayos Cochinos)

The value of fish and invertebrates, both freshwater and marine, bound for the aquarium trade has been valued at USD 15 billion annually. The majority of these animals are harvested from the wild by local fishers. As the demand by hobbyists for coveted species rises, local reef communities are overexploited by these fishers who, until recently, were subsistence fishers and only lately have been forced by the lack of economic opportunities to turn to the harvesting of marine ornamentals. The percentage of animals supplied by aquaculture grows each year and culture of ornamentals is the fourth largest aquaculture industry in the US. But as the list of species supplied by aquaculture grows, the need for wild caught specimens decreases, eliminating the need for fisheries in areas where the loss of income is devastating. Whereas a large impetus behind aquaculturing these animals is safeguarding the environment, the resulting impact on the local economy is not a minor one. The reaction has been a call for the transfer of low-technology culture techniques to local communities as a viable alternative to collection from the wild. This topic involves working alongside an international expert in aquaculture who is examining how aquaculture of reef species could be undertaken in the fishing communities of the northern Honduran coast. The resultant report will identify the proposed system of holding tanks or net pens that will need to be constructed on shore or in a lagoon area. The report will also describe how pre-settlement larvae can be collected by net to be grown out, and reef fish in large numbers that occupy a territory such as basslets, gobies, and hamlets can be used as broodstock. The final part of the report will be concerned with the marketing and shipping possibilities. Working alongside this expert will enable students to develop dissertations on how this business could benefit the Garifuna community and the likely impacts of the business.

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