Fisheries topics

Country codes: HO (Honduras), IN (Indonesia), MA (Madagascar), ME (Mexico), PE (Peru), SA (South Africa)

HO15 Managing the Caribbean lionfish invasion

Lionfish are an invasive species in the Caribbean and are having a devastating impact on local fish communities throughout the region. Introduced in the 1980s, believed to be by accident, lionfish have spread extremely quickly and are now found as far as New York City and Brazil. Their success is down to a number of factors, including their high reproductive rate, generalism in terms of both diet and habitat, and a lack of natural predators. They are now considered to be one of the greatest threats to the future of Caribbean coral reefs and their fish communities. Management approaches to dealing with the lionfish invasion are limited, with one of the most common being direct removal via spear fishing. This relies on regular visitation to individual reef sites, as studies have shown full recovery of lionfish populations only five months after complete removal. Baseline data will be collected on population densities of lionfish at sites of varying intensities of culling. Lionfish will subsequently be removed and morphometric measurements taken along with dissections for physiological and gut content assessments, which can link fish assessments to gauge prey availability. In addition, lionfish behavioural responses to divers, such as Flight Initiation Distance (FID) and Alert Distance (AD) can be assessed, which could also be expanded to include commercially valuable fish such as grouper.

Extended Project Summary

HO21 The behaviour of invasive lionfish on Caribbean reefs

The invasion of lionfish in the Caribbean has developed into one of the greatest threats to the survival of the region’s coral reefs thanks to the devastating effect they have on native fish populations. Research has naturally focused on mapping the spread of lionfish, quantifying their ecological impacts, and exploring management interventions to reduce their numbers. However, improving our understanding of the behaviour of this species on non-native reefs is of particular interest to better grasp the underlying success of their invasion. This project will assess lionfish behaviour both on the reefs and in a small laboratory, where individuals will be captured and analysed based on a set of carefully designed treatments. Particular focuses of this work could include prey selectivity, and habitat preferences to investigate the cryptic nature of this species, and data can be linked to ecological characteristics of the reef itself.

Extended Project Summary

HO22 Assessing the population status of the Caribbean spiny lobster, Panulirus argus, on a unique coral reef ecosystem

As a mesopredator, the Caribbean spiny lobster (Panulirus argus) feeds upon a wide range of resources including many species of snail, crustacean and sea urchin, but is also predated by numerous larger reef-dwelling organisms such as sharks, snappers and groupers. P. argus therefore sits at the centre of Caribbean coral reef food webs, meaning that changes in population size can lead to dramatic trophic cascades affecting the entirety of the reef system. As well as being ecologically important, lobsters are also hugely economically valuable and it is estimated that over-harvesting has reduced P. argus populations by up to 50% in some parts of the Caribbean since the 1950s. Despite these dramatic population declines, P. argus has been assessed as ‘data deficient’ by the IUCN and is therefore afforded little protection. Caribbean spiny lobsters in Honduras have been largely neglected by the scientific community, but this project aims to redress this by using a combination of in situ population surveys to assess their size-distribution structure and habitat selectivity, and lab-based experiments to investigate basic facets of their behaviour and physiology. We hope these data will ultimately be used to increase the degree of protection provided to the Caribbean spiny lobster and prevent further declines to their population sizes.

IN33 Fisheries research in local communities

Opwall have been working with local fishing communities in the Wakatobi for almost 20 years, developing a deep understanding of the conservation issues associated with declining fish stocks and producing several award winning dissertations along the way. Opportunities exist for students to build on this extensive experience by completing dissertation projects focusing on artisanal fishing pressure by working alongside Opwall staff and local Indonesian partners in small fishing communities on and around Kaledupa island. To talk about this opportunity, and how it might be suitable for your undergraduate or masters dissertation research, please email Dr Dan Exton: