School of Biological Sciences
Dr Gordon J. Watson
Researchers within my group focus on the interaction of humans with the marine environment. This is undertaken in a wide range of ecosystems and habitats from tropical reefs to intertidal soft sediments, but with particular emphasis on coastal areas. Three main areas are covered with case studies from each given below. The work has been funded by organisations such as the EU, Leverhulme Trust, The Crown Estate, Natural England and the University of Portsmouth.
For a list of publications please see my staff profile page
Focussing on polychaetes and with funding from a number of EU projects our aim is to investigate the impact of pollutants on marine ecosystems. Using a suite of different end points from behavioural changes to cellular and genetic biomarkers we aim to understand the impact on an individual, but also how this affects the benthic system.
Case Study: Impact of zinc and copper on invertebrates
The King ragworm, Nereis virens, is an ecologically and commercially important polychaete species of soft sediment inter-tidal communities throughout the northern hemisphere and is known to be impacted by various anthropogenic activities. Metals such as Cu and Zn are naturally present in the ecosystem but can be found at high levels due to industrial activities and therefore may have an impact on polychaete species.
The objectives of the project are to: 1. identify and quantify the bioavailable concentrations of heavy metals, Cu and Zn in the natural habitat of the polychaete N. virens and 2. establish the impacts of chronic exposure of Cu and Zn on N. virens through the use: Physiological, behavioural, cellular and genotoxic endpoints.
Image: The king ragworm Nereis virens.
The marine tropical marine aquarium trade is a global industry that sets a premium on diversity and rarity. Collection of live invertebrates from coral reefs has increased dramatically over the past two decades. Aquaculture of ornamental species is deemed a priority solution in mitigating the effects of wild collection but expanding the range of species is limited by bottlenecks at key life history stages. We have developed novel culture methods for a range of marine invertebrates collected for the trade.
Case Study: Invertebrate aquaculture for the marine aquarium trade
The current fishery activities of the marine aquarium trade are raising concerns over sustainability. The majority of livestock supplied to hobbyists is taken from the wild, and as the hobby grows due to advances in husbandry and technology, wild populations face over-exploitation. Unlike the marine hobby, around 90% of freshwater ornamental species are currently cultured in captivity, and therefore aquaculture has been suggested as a potential solution to the sustainability problems the marine ornamental trade is facing. However, development of commercially viable techniques for many species has been difficult. This is due to bottlenecks forming at key stages as a result of complicated life histories and also the time taken to grow to marketable size.
This project funded by UK-Bred Ltd. will aim to investigate if popular invertebrate species can be cultured on a commercial scale, ultimately providing an alternative to the wild harvest of animals from coral reefs in order to reduce the impact on these vital ecosystems. Initially a worldwide survey of hobbyists, and a UK-wide survey for retailers will be carried out to determine which invertebrate species are being routinely sold and kept, which will then inform the choice of species for the subsequent reproductive trials.
Case Study: Aquaculture of fanworms using regeneration
Worldwide, over 2 million people own marine aquariums and millions of invertebrates are traded around the world every year to support this hobby. As the vast majority are taken directly from coral reefs this has led to significant over-collection of some species and damage to the reefs during their removal.
Marine worms are common in many aquariums, but only two groups (Christmas tree and fan worms) are collected routinely. Fan worms are the most popular and are, therefore, the focus of this project. Fan worm aquaculture was approached using a method similar to that of taking cuttings from plants: the production of new individuals by making fragments of the parent. Fan worms, like many other worms, have excellent powers of regeneration. Each worm may have hundreds of segments, but as few as 20 can regenerate a complete worm through segment reorganisation and regeneration of missing structures. It is this principle that has been exploited in this project to investigate the feasibility of fan worm regeneration as a method of aquaculture to supply the industry.
Image: Sabellid fan worm
Our group is at the forefront Marine Protected Area (MPA) and evaluation in the current UK marine conservation process. The protection of intertidal mudflats and the benthic community within them is a key goal of Special Areas of Conservation and European Marine Site legislation.
Case study: Management of bait collection in Marine Protected Areas
Bait collection is a contentious worldwide issue as it damages benthic communities, disturbs birds and alters sediment characteristics of intertidal mudflats so local MPAs have been established to meet the primary objectives (protect these habitats and maximise shore safety). We have evaluated different local conservation methodologies in the UK using CCTV cameras to monitor digging activity and confirm if diggers adhere to the rules. The efficacy of an educational approach (a voluntary Bait Collectors’ Code leaflet) was also assessed via direct discussion and collector observation. Locally-driven marine conservation management is relatively cheap and is effective, but only if the key ‘rules’ are followed.
Image: Screen grab of a video recording from CCTV system in Chichester Harbour. Bait diggers can be seen on the shore circled in red.
Case study: Using historical datasets to understand benthic community change and conservation
On England’s southern coast, the highly populated Solent region supports industrial and recreational activities, but is at the same time an ecologically important region with much of the coastal area designated as protected sites (SACs, SPAs, SSSIs). This project focuses on the intertidal mudflats which support macroinvertebrate communities that are an essential source of food for fish and birds, but also function in other valuable processes in the coastal system (e.g. nutrient cycling).
With a legal obligation for maintaining mudflats and the benthic community in “favorable condition”, several questions will be addressed using historical datasets combined with current sampling
- How do communities change over time?
- What is driving change?
- At what scale does change occur?
- Is change “favorable,” ecologically?
Image: Sampling in the Solent, summer 2014
Current team members
Dr Katrin Bohn