IAP-25-120
Sustainability in creel fisheries
Background and importance.
Marine ecosystems worldwide are subject to challenges arising from adverse ecological effects associated with fishing activities, including those associated with the use of passive or static gears such as traps, pots, and creels. Trap gear fisheries (e.g., creels) are often referred to as sustainable compared to other fishing methods, as they typically involve lower fuel use, reduced bottom contact and diminished habitat damage compared to some active fishing gear types such as trawls [1]. However, passive gears are often specifically associated with some other challenges (e.g. [2]). These challenges include impacts on marine biodiversity through bycatch of unwanted species or juvenile individuals (see, for example, [3]) as well as reliance on substantial amounts of bait. Specifically, since the capture mechanism in creels relies on the use of bait, this raises concerns related to the (1) reliance on other commercial fisheries for bait and (2) the use of substantial quantities of bait to capture target animals [4-6]. The reliance on bait from wild-capture fisheries has both economic and environmental implications, including increased carbon footprint from additional fishing and transport.
Further research needs to be addressed.
The extent and magnitude of the above-mentioned challenges often differ between fishing areas due to environmental conditions, fishing effort, fishing gear type and main target and bycatch species. Although these issues are frequently addressed in the scientific literature, many remain unresolved for specific fisheries and their associated environments, with creel fisheries in particular often lacking adequate scientific data and comprehensive investigation. The creel fishery targeting crustaceans such as lobster (Homarus gammarus) and brown crab (Cancer pagurus) is one such example. This type of fishery is widely used in the UK, including Scotland, and faces the aforementioned sustainability challenges. These research needs will be addressed by this PhD project.
Project aims.
This PhD project will focus on creel fisheries in Scotland, and approaches on how to improve sustainability in creel fisheries. This aim will be addressed by systematically assessing the key issues in typical creel fisheries targeting brown crab and lobster in Scotland. The scientific topics to be addressed during a 3.5-year PhD period will include the following:
(Q1) assessment of effects of creel fisheries on surrounding fauna by examining the catch composition of bycatch species caught in the brown crab and lobster fisheries in Scotland.
(Q2) assessment of the bait use in these creel fisheries and tests of using alternative bait sources in a creel fishery and compare fishing performance and cost effectiveness.
(Q3) identification of technical improvements to reduce bycatch rates of juvenile target species in these creel fisheries based on systematic-literature reviews.
(Q4) laboratory and field testing of potential modifications in creel design (e.g. adaptations from other fisheries) which may lead to reductions in crustacean bycatch levels, and associated size selectivity analyses.
Expected impact.
The research taking place in this PhD project will be related to potential applications in creel fisheries to improve their sustainability. The candidate is expected to improve networking skills and share the results in international forums (e.g. ICES Working Group on Biology and Life History of Crabs or ICES-FAO Working Group on Fishing Technology and Fish Behaviour). The results are expected to be used by the student for networking activities that will allow improvement of the student’s presentation skills and collaboration with relevant partners and other fisheries. The results will also be used in further teaching activities and meetings with stakeholders.
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Image Captions
Figure 1. Outline of the approach for this PhD
Methodology
The practical approach planned during this PhD project will consist of the activities listed below.
First, the project will aim to estimate creel fisheries effect on non-target species (Q1).The candidate will assess catch composition in existing creel fisheries, with a particular focus on bycatch, including juvenile brown crab and lobster and other non-target species. This will involve systematically assessing available information (conducting systematic literature review) and filling research gaps through new data collection at sea. New data will be collected by monitoring of catches and, where relevant, the application of video recording analysis. The second part of the project will estimate fishing performance and cost effectiveness of using alternative bait sources in a creel fisheries targeting lobster and brown crab (Q2).
The third part (Q3) will focus on proposing measures on how to limit bycatch on undersized target individuals and bycatch species in creel fishery. A systematic review of the existing literature will be conducted to identify potential technical measures employed in creel fisheries to mitigate bycatch, and, where data permit, to evaluate the effectiveness of these measures in reducing bycatch. Finally, the practical work at the final stage of the project (Q4) will be conducted in field and in a laboratory where the candidate will assess the morphology of selected species based on previously well-established methodology (e.g., [7]). Specifically, the candidate will conduct field and lab-based studies to determine the influence of escape gap size and shape for achieving optimal size selection and thereby reducing bycatch in the brown crab and lobster fishery, thus improving sustainability in this fishery.
The results are expected to provide content sufficient for at least three scientific publications that will correspond to three chapters of a PhD thesis that are based on scientific studies.
The overview of the approach for this PhD project is outlined in the attached figure.
Project Timeline
Year 1
Based on methodology described above, the key activities for Year 1 will include:
1.1. Work with the supervisory team and collaborators to define the spatial extent of the study and activities (approx. 10% of Year 1).
1.2. Undertake necessary research training (approx. 10% of Year 1), e.g. through PGCert style programmes / opportunities.
1.3. Undertake necessary training for performing the outlined tasks (i.e., training for performing a systematic literature review, meta-analysis) (approx. 10% of Year 1).
1.4. Undertake training for seagoing activities (approx. 5% of Year 1).
1.5. Complete ethics assessments and data management plan (approx. 5% of Year 1).
1.6. Plan and address Q1 regarding identification of present challenges in selected creel fisheries, write the respective chapter based on systematic literature review (approx. 60% of Year 1).
Year 2
Based on methodology described above, the key activities for Year 2 will include:
2.1. Participate in PhD level fishing gear technology course (approx. 15% of Year 2).
2.2. Work on testing alternative bait use in creel fisheries (Q2) and write up results
(approx. 45% of Year 2).
2.3. Work on systematic literature review identifying potential measures for reducing
bycatch in creel fisheries (Q3), write the respective chapter (approx. 40% of Year 2).
Year 3
Based on methodology described above, the key activities for Year 3 will include:
3.1. Perform laboratory experiments addressing Q3 and Q4 and write up results (approx.
40% of Year 3).
3.2. Prepare and test innovative designs in selected fishery; write up results (Q4)
(approx. 55% of Year 3).
3.3. Present selected results at a scientific conference/meeting (approx. 5% of Year 3).
Year 3.5
Based on the methodology described above, the key activities for the last 6 months of this project will include focusing on finalising the PhD research work and focus on the main conclusions and discussions based on chapters answering research questions 1 – 4 as outlined above.
Training
& Skills
The candidate will be based primarily at Heriot-Watt University (preferably 100% on Orkney campus or spending substantial part of their time in Orkney if working also from Edinburgh campus in collaboration with third supervisor working in Lyell Centre). Specific training events and research support will also take place at Heriot-Watt University Edinburgh campus. Research stay in partner university is going to be organised to work in collaboration with secondary supervisor from University of St Andrews.
The candidate will focus on the following training for field, laboratory work, data gathering and research:
1. Research training programmes and opportunities through the PGCert,
2. Safety training for sea-going research trips,
3. Safety training for working in a laboratory.
Further, the training and skills will include:
4. Training for performing research ethics assessments and how to devise a data management plan,
5. Statistics skills depending on the background of the candidate,
6. PhD level course in fishing gear technology research or equivalent,
7. Presentation skills,
8. Data synthesis and meta-analysis skills.
References & further reading
[1] Suuronen et al. (2012), doi: 10.1016/j.fishres.2011.12.009. [2] Gilman et al. (2021), doi: doi.org/10.1038/s41598-021-86123-3. [3] Lively & McKenzie (2023), doi: 10.1016/bs.amb.2023.07.001. [4] Driscoll et al. (2015), doi: 10.1016/j.fishres.2015.08.007. [5] Spoors et al. (2021), doi: 10.1016/j.fishres.2021.105974. [6] Cerbule et al. (2023), doi: 10.1016/j.heliyon.2023.e13820. [7] Herrmann et al. (2021), doi: 10.1016/j.ocecoaman.2020.105495.
