Marine Pathways Project - Monitoring for NNS

In order to manage and control NNS an understanding of the current abundance and distribution of NNS is required. In addition, to be able to respond rapidly to NNS introductions and limit subsequent spread and minimise impact, early detection of NNS introductions is crucial. Monitoring and surveillance of NNS to determine abundance and distribution and detect introductions rapidly will therefore be key to NNS control and management. Four projects concerned with the practical approach to NNS monitoring were being conducted as part of the marine pathways project:

  • Welsh inshore monitoring network.
  • Offshore monitoring of mooring buoys around Great Britain.
  • Inshore and offshore monitoring work in Scotland.
  • Citizen science for monitoring NNS.

In addition, a desk based study was conducted to investigate marine monitoring and its potential to be adapted and used to monitor NNS:

  • Current marine monitoring and its potential to be adapted and used to monitor NNS.

Please see below for more details.

Trial Oyster Bag deployed at the Menai Strait site

Welsh inshore monitoring network

An 18-month project to develop an early warning system for detecting NNS in Welsh coastal waters was undertaken. During the project, the research scientists worked closely with coastal-based industries in Wales including oyster farmers, marina operators and lobster and crab fishermen to identify the optimum ways to detect new marine invasions.

A 1-month trial at an oyster farm in the Menai Straits to test the proposed monitoring method for aquaculture sites was successfully completed. Additional experimental work also took place from Spring to Autumn 2014.

The results obtained from the project will aid Wales to develop a robust system for finding marine NNS in the early stages of establishment. This will increase the number of management options available and reduce the economic and environmental costs associated with invasive NNS. The project ended March 2015. This work was supported by Natural Resources Wales and carried out by Bangor University.

Wales Marine Non-native Species Inshore Monitoring Network (Bangor University 2015)

Offshore monitoring of mooring buoys around Great Britain

Offshore mooring buoys provide a potential tool in the early detection of NNS introductions into marine waters given their offshore location and their frequent servicing. Work under the marine pathways project was undertaken using 5 offshore mooring buoys to:

  1. Determine whether there is potential for marine NNS to attach to offshore structures such as buoys.
  2. Investigate sampling and identification techniques which will allow the detection of marine NNS attached to offshore structures. Sampling techniques being investigated include both scrapes and settlement panels.
  3. Assess the overall merit of using buoys and potentially other offshore structures as an early warning system for the introduction of marine NNS into UK coastal waters.


This work was completed in March 2015 and was led by Cefas.

Marine non-indigenous species monitoring and risk management (Cefas 2014)

Left: scrape samples being taken from a recovered offshore buoy. Right: location of buoys used in the offshore monitoring project

Offshore monitoring buoy recovered from sea covered in marine species

Inshore and Offshore monitoring in Scotland

The main aim of this work is to trial a means of detecting non-native marine species in inshore and offshore Scottish waters.

Settlement plates or scrape samples were used at a variety of sites to collect samples of both algae and fauna. The sample sites were:

  • Four offshore buoys
  • Two inshore buoys
  • Two marinas (Oban and Tarbert)
  • Two shell fish farms (Loch Fyne, Loch Creran)
  • Two fin fish farm (Lynne of Lorne, Loch Fyne)

A large amount of biological material was collected, requiring specialist identification. Analysis of the collected material aimed to:

  • determine the suitability of scrapes versus installation of settlement panels and photographs (rapid assessment will also be performed to collect baseline data) to detect non-native macro algae and fauna
  • determine the most cost-effective number of scrapes required at each inshore site to give 95% confidence of identifying all NNS present
  • trial the effectiveness of analysing for a hit list of species based on recent surveys and DEFRA horizon scanning exercise versus complete analysis.

This was a collaborative project between The Scottish Association for Marine Science, Scottish Government and Scottish Natural Heritage.

Assessing the effectiveness of early warning systems for the detection of marine invasive non-native species (Cook, E. J., Beveridge, C., Twigg, G & Macleod, A., 2015)

Photographing settlement panels

Citizen science for monitoring NNS

This part of the marine pathways project investigated the efficacy of citizen science relative to other methods for monitoring marine NNS. Cornwall Wildlife Trust, in collaboration with the Marine Biological Association of the United Kingdom, has developed a citizen science programme as part of their Local Action Group work on marine NNS surveillance. One aim of the programme was to build a network of volunteers to gather data on marine NNS by recruiting boat owners to deploy settlement panels from the pontoon at their marina berth. Participants in the panel project were required to submit digital images of their colonised panels after a minimum period of eight weeks’ immersion. The images were then inspected by experts for the presence of NNS. The project design aimed to provide verifiable biological data on the presence of a range of taxa across a wide geographical area. Also, the project aimed to raise awareness of the impact of NNS within the recreational boating community.

This project evaluated the efficacy of using volunteers to provide photographic surveillance by comparison with data from traditional sampling methods.

The specific aims of this project were:

  • To evaluate the adequacy of photographic images taken using a range of camera equipment e.g. high specification and resolution vs. amateur equipment.
  • Comparison of photographic data vs. laboratory assessment of preserved panels.
  • Comparison and evaluation of Rapid Assessment Surveys (RAS) undertaken by experts vs. settlement panel sampling.
  • Examine how techniques could be utilised as part of the Marine Strategy Framework Directive (MSFD) monitoring programme.
  • Provide guidance for spatial distribution of panels to provide effective detection of marine NNS.

Investigating the efficacy of citizen science for monitoring marine invasive non-native species (Cefas 2014)

Current marine monitoring and its potential to be adapted and used to monitor NNS

The marine environment is heavily monitored, however NNS are not the focus of the monitoring undertaken. As part of the marine pathways project, a study was conducted by Cefas in 2013/2014 to investigate the adaptability and applicability of current monitoring in the management and control of NNS.

The key objectives of the study were to:

  1. Assess current UK marine monitoring programmes and gather information relevant to their potential use in a monitoring programme for NNS.
  2. Determine the suitability of the monitoring programmes to detect NNS.
  3. Assess geographical coverage of the monitoring programmes.
  4. Assess the geographical coverage in relation to different taxonomic groups.

Consideration was also given to whether current monitoring is being conducted at locations which may be at high risk of introduction of NNS (more information on the assessment of the introduction of NNS into marine waters of GB and Ireland can be found on the page: NNS introduction pathways assessment).

This project has commented on the feasibility of adaptation and amendment of current monitoring to include NNS. This project, in addition to the projects undertaken to investigate the practicalities of inshore and offshore monitoring, has contributed to the development and implementation of a monitoring strategy for NNS.

Marine non-indigenous species monitoring and risk management (Cefas 2014)

Monitoring sites of the statutory monitoring programmes


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