Kenneth Ruiz

Abstract

 The means by which a reversal of the trend in the anthropogenic decline of habitats and species, observed worldwide, might be implemented locally in Gibraltar, form the basis of this study. Taking into account geo-biological limitations of various nature-based solutions and avoiding the introduction of non-native species, two case studies are discussed.

The first case study would see the re-introduction of a seagrass habitat to Gibraltar, present until the relatively recent past. Such a re-introduction would have numerous additional benefits, including mitigation of climate change by Carbon sequestration. The second case study would enhance  man-made habitat type – artificial rocky shores – by increasing the habitat heterogeneity of such structures, in the intertidal zone. The associated benefits of the artificial rocky shores case study are fewer than those of the

seagrass study. Both are desk-top feasibility studies, from literature reviews of the relevant topics to detailed methods, site preferences and costs.

Literature reviews identified gaps in the current knowledge, and both case studies seek to address some of the gaps, by the design of methods  employed in their respective implementations. There are fewer opportunities  to innovate in the case study involving the much more thoroughly-studied topic of the reintroduction of seagrasses, than there are when attempting to  enhance the biodiversity on artificial rocky shores. The place of the case studies within the United Nations’ Sustainable Development Goals is considered, and locating study areas close to each other is encouraged so that food webs may mingle and a synergistic relationship might develop, further enhancing biodiversity.

Primary Supervisor:               Dr Awantha Dissanayake

Secondary Supervisor:          Dr Darren Fa

Aviad Reed

Abstract

Due to the increase in climate change resulting in sea levels rising globally; an ever-increasing global population; and increased demand for food and natural resources that are being depleted, there is currently a need for nature-based solutions to combat climate change and storm protection and to achieve food security. This thesis has focused on Gibraltar as it is practically surrounded by sea, with the Mediterranean Sea on its eastern side and the Atlantic Ocean to its west. This thesis has investigated the use of mussel farming as a way to combat all the above. A literature review into the topic of the use of mussels for wave attenuation and as a food supply shows that there has been a shift towards restoration projects around the world, predominantly involving oysters. There have been several examples of the way mussels have been employed for the reduction of eutrophication and increasing the food supply in small local communities around the world. Furthermore, this thesis has looked at ways of funding such projects, with reference to the market value of the mussel industry globally, which is currently estimated at USD $ 2.6 billion in total, with an estimated USD $ 4.05 per kilogram of mussels. In addition, there is an added value from mussels as a local inhabitant in the ecosystem, with an increase in biodiversity. An in situ practical application of the combination of using mussel farms for wave attenuation and food supply as a self-sustaining business was not identified in this thesis, although an investigation of the information that was available for recommendations was made, based on projects with similar attributes from around the globe. Further research needs to be conducted into this field of thought to determine costs and feasibility for the use of mussel farming in Gibraltar.