MSc
Master in Marine Science & Climate Change
Designed and delivered by expert academics and scientists, this full or part-time interdisciplinary programme blends theoretical s[...]
Research Project Overview
The aim of my project was to assess the impacts and pressures of Marine Recreational Fishing (MRF) on Europa Reef. To determine the marine recreational fishing effort (MRFE) a novel methodology was employed where in situ surveying was carried out by land-based visual surveys. Surveys involved measuring the fishing effort (number of fishing rods) and number of vessels effort to attain an idea of total marine recreational effort. At the same time, I compared the fishing area (Europa Reef) with a No-Take Zone (Seven Sisters) with BRUV (Baited Remote Underwater Video) deployments to compare the abundance and diversity between sites and conclude if MRF is having a negative impact on Gibraltar’s reef.
The results of this study showed an increase in fishing activity from morning to evening (study conducted in Summer) with little activity during the mornings (5.45 hours of total effort), and a ten-fold increase recorded during the evenings (54 hours of total effort). The total MRFE was 110 hours. After comparing the diversity and abundance of both sites, higher overall fish numbers were observed in Seven Sisters (n= 6396) compared to Europa Reef (n = 1522). Seven Sisters also had a higher number of species (n=18). The difference between sites was more evident in fish species targeted by anglers where from the nine species targeted 7 were more abundant in Seven Sisters. The results could indicate that Gibraltar’s MRF is having a significant impact on the reef and a process of ‘fishing down the food web’ could be occurring. Without effective marine management, the sustainability of local fish stocks and the reef could be at risk.
Quantitative methods were used in the project. A literature review was conducted prior to the fieldwork to identify any gaps in research and gather the current global knowledge on marine recreational fisheries. This project included a wide range of components, which taught me a broad range of applicable abilities, which included designing and delivering fieldwork-based research, building a baited remoted underwater vehicle (BRUV) and deployment in a high energy underwater environment, working with different software and statistical methods (PRIMER, Excel, SPSS and BIIGLE), land and boat surveying, and learning taxonomic identification skills.
WHY SHOULD THE PUBLIC KNOW ABOUT THIS TOPIC?
There are two main reasons why people should know. Firstly, the ecological importance that reef habitats have on the environment. Reefs are crucial components of ecosystems as they provide an environment that fosters the diversity and abundance of several taxa. They provide crucial ecosystem services such as habitat for the species that inhabit it, as well as having biotic, physical, biogeochemical, social, and cultural functions. Moreover, Gibraltar’s reefs are considered one of most important spots for biodiversity and fish abundance despite the historical record of overexploitation of the area. Secondly, is the impact that MRF has on the marine environment. MRF has been proven that can have the same or more impact than commercial fishing and could cause overfishing and eventually cause an effect of ‘fishing down the food web’. The impact of the boats adds to the direct impact of catching and taking the fish out of their habitat.
WHAT IS THE WIDER IMPACT OF YOUR RESEARCH?
On a global scale my research is the first to use a mixed methodology that measures the fishing effort and compares a fishing zone with a non-fishing zone, both in situ. The fishing effort was assessed through direct observations from land while the methodology used for the comparation was with BRUV deployments. These methods can be added to the existing and more common methodologies to improve the MRF research and understand better the effects that it has on the oceans.
On a regional scale the research can provide advice to Gibraltar’s Government, like continuous research of the fish stocks and the health of the reef, monitoring and enforcement of the MRF through different types of surveys and a potential no-take zone in Europa Reef, that allows the recovery of the habitat. To ensure people are able to enjoy fishing for generations to come, measures are required to allow for recovery, protection and conservation of the reef and its features.
COMMENTS FROM HEAD OF SCHOOL
Xavi’s work builds on previous work from the School of Marine Science (Clive Crisp, 2020) and is the first to quantify Marine Recreational Fishing effort through land-based surveys and simultaneous assessment of reef health (through fish surveys). He has found that fishing effort may be a driver for reduced fish abundance and diversity within Europa Reef. To enable people to continue to enjoy fishing and, therefore, sustainable fishing, it is recommended that measures be put in place to allow for continuous monitoring of reef health and fish biodiversity and abundance.
Dr Awantha Dissanayake,
Head of School (Marine & Environmental Sciences)
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