Marine Biofouling: Non-Indigenous Species and Management Across Sectors

GESAMP Working Group 44

Abstract

The biofouling of submerged anthropogenic surfaces and factors that contribute to the spread of non-indigenous species (NIS)
have both received substantial attention from researchers, regulators and the private sector focused on understanding their
economic, social and environmental consequences. This work has informed the development and implementation of sustainable
management approaches, for the prevention of a range of harmful impacts. All marine commercial and recreational sectors deal
with biofouling and its varied but typically undesirable consequences. Similarly, almost all marine resource managers, from local
to global scale, are concerned with the threat of invasive species and their vectors. This review is an effort by the GESAMP WG 44 to
look at the interface between these two pervasive challenges.
Various strategies and tools to prevent, reduce or manage biofouling have been developed and adopted. The intent ofthese efforts
has been primarily to combat the direct negative consequences of biofouling communities on the performance and structural
integrity ofthe surfaces to which the communities attach. The potential for biofouling to be a vector for invasive species has usually
been a secondary consideration. Although the strategies, tools and associated regulatory measures are typically developed by
experts working within a specific aquatic sector, uptake of successful actions by other sectors is common.
Currently, all of the strategies, tools or regulatory measures have both strengths and limitations, which can vary greatly with
the context in which they are applied. This report first reviews the more general consequences of biofouling (Chapter 2) and the
strengths and limitations of the most common strategies, technical measures and policies for preventing and managing biofouling
(Chapter 3). This information sets the context in which to examine how effectively each commercial and recreational sector currently
can deal with biofouling, its impacts and the potential unintended consequences of antifouling or biofouling removal approaches.
This examination was conducted sector by sector (Chapter 4), because some strengths or weaknesses of each individual measure
or policy may affect suitability and performance differently in the various marine sectors. Moreover, although biofouling may
present a pathway for movement of NIS in each sector, the primary risks associated with each sector may also differ. Thus,
within Chapter 4, for each sector, the report examines which policies, measures and regulatory actions are commonly used,
the rationales for the preferences, and how these choices affect the potential for the sector to manage the risk of transfer of NIS
through biofouling. Opportunities to increase the effectiveness in preventing or reducing the transmission of invasive species
through adapting improving existing policies, measures and regulations, or adopting additional ones, are highlighted. The sectors
examined are vessels (subdivided into shipping, fishing and recreational sectors), aquaculture, marine offshore energy, offshore
renewable energy, ocean-observing infrastructure (i.e. monitoring and research instrumentation) and marine debris.
The report finds that, for each sector, there is no single ‘best solution’. Various combinations of policies, measures and regulations are necessary for the effective prevention or control of biofouling and NIS. Regulatory frameworks with clear standards can
contribute to managing the risk of biofouling as a pathway for the spread of invasive species but must be appropriate for the sector.
Effective frameworks also must be supported by adequate monitoring and capacity to ensure compliance, regularly updated as
additional knowledge and innovations become available, and must not cause other unintended environmental consequences.
Moreover, performance will remain context-specific even for combinations of measures, making ongoing monitoring, information
sharing within and among sectors and adaptive management essential. Some of these emergent lessons and priority knowledge
gaps are summarized in Chapter 5.

Citation

GESAMP Working Group 44. (2024). Marine Biofouling: Non-Indigenous Species and Management Across Sectors. Paris: International Maritime Organization

• Report Type: Project Report
• Online Publication Date: Jul 22, 2024
• Publication Date: Jul 22, 2024
• Deposit Date: Jan 22, 2025
• Series Title: GESAMP
• Series Number: 114
• Series ISSN: 1020-4873
• Public URL: https://hull-repository.worktribe.com/output/5007392
• Publisher URL: http://www.gesamp.org/publications/marine-biofouling-non-indigenous-species-and-management-across-sectors