Leslie Roberson

Working with the fishing industry to collect critical bycatch data in Moreton Bay

The otter bottom trawl sector, primarily targeting prawns, is the largest fishery operating in Queensland and one of the most valuable sectors nationally. The fleet operating in Moreton Bay is the largest commercial fishery within the Marine Park. However, managent of Moreton Bay presents challenges due to its unique ecology, high population density, and diverse stakeholders. Bottom trawl gear type can produce severe environmental impacts, including damage to the seabed and high rates of bycatch (non-target and discarded catch), sometimes as high as five times the volume of landed catch. This can include species of conservation concern such as rays, sharks, sawfish, and sea snakes. Bycatch is a financial, environmental, and social problem; it reduces the efficiency of the fishing operations, threatens biodiversity, and creates a negative public perception of the fishery.

Historically, “silver bullet” solutions to bycatch problems that are implemented across the industry have yielded limited success, largely due to the distinct bycatch profiles and variable fishing practices in different trawl regions. For instance, anecdotal evidence suggests the Moreton Bay catch profile significantly differs from that of larger vessels operating outside the bay. For instance, there are likely more small stingrays caught inside the bay compared to larger individuals in deeper water. Unfortunately, dedicated bycatch surveys are scarce, leaving a gap in understanding of the evolving ecology of Moreton Bay and the characteristics of the trawl fishery.

This project will undertake the first dedicated bycatch sampling in Moreton Bay trawls in 20 years—and the first independent data collection since Bycatch Reduction Devices became mandatory—aiming to collect empirical data on current fishing practices and bycatch profiles. A key aim is to foster collaboration among commercial fishers, industry representatives, researchers, and managers to investigate bycatch issues in Australia's prawn trawl fishery, with a specific focus on Moreton Bay. By doing so, the project aims to raise awareness about problematic bycatch species (e.g., sea snakes, sharks, rays) and gain insights into when, where, and why they are prevalent. The project also seeks to identify and document existing bycatch reduction strategies employed by fishers, such as innovative configurations of Bycatch Reduction Devices and other nuanced and unrecorded operational tactics that could further reduce interactions with threatened or protected species. Additionally, it aims to document potential solutions and outline the necessary next steps for implementation. The project will draw insights from historical data, comparing contemporary bycatch profiles with information collected during the previous study in the early 2000s. The project strives to pave the way for collaborative, effective, and localized solutions that enhance the sustainability of Queensland's fisheries, while fostering better understanding among diverse stakeholders.

Leveraging the abilities of individual fishers to reduce bycatch in fisheries

This is a large project with over two dozen international and Australia-based partners. There are various opportunities for students to work on datasets in collaboration with partners.

Global bycatch risk assessment for odontocetes in pelagic longline fisheries

Operational interactions between odontocetes (toothed whales) and pelagic longline gear are a global phenomenon that jeopardizes the economic viability of longline fisheries, and may pose a significant threat to odontocete populations. Most interactions occur when whales attempt to steal bait or target catch (“depredation” ) and become hooked or entangled in the process. The risk of interactions is not well understood but scattered data indicate that at least 20 species may be implicated, and available empirical data indicates that interactions with longlines could be a key threat to odontocetes populations in some regions. Reliable empirical data on fishing effort and catch are limited, a problem that is further exacerbated by chronic underreporting of bycatch in fisheries logbooks. However, insights from anecdotal, qualitative, and unverified sources suggest that the magnitude of the problem may be significant at a global scale and could affect a wider variety of odontocetes species than what has been reported.

To date, there has not been a comprehensive analysis of risk of odontocetes bycatch in pelagic longlines across geographic areas and species' ranges. The analysis will combine published information on bycatch rates, species distribution maps, and publicly available fishing effort data from Global Fishing Watch. By estimating the global extent of bycatch risk and hotspot areas for odontocetes species known to interact with longlines, this analysis will provide valuable insights into the magnitude and distribution of the problem. The results of this project will help inform current efforts to develop effective management strategies and conservation efforts to mitigate this problem.

This project offers the opportunity to lead a collaboration with an international group of experts on fisheries bycatch, including Dr Rob Williams (Pew Fellow, Oceans Initiative), Dr Robin Baird (University of Hawaii) and A/Prof Jeremy Kiszka (Florida International University). It will be supervised by Dr Leslie Roberson but is flexible regarding additional UQ or Australia-based supervisors or collaborators. Some preliminary work has already been done, providing the student with a solid foundation of code, data, and information to build from.