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Biofouling Risk

1.0 Introduction

The Vessel-Check portal provides an indicative risk assessment of a vessel's biofouling management practices, to aid vessel owners/operators and biosecurity management agencies in determining whether a vessel is achieving best practice in biofouling management (i.e. in-line with the IMO biofouling guidelines) as much as reasonably practicable. The portal is a decision support system for both vessel owners/operators and biosecurity regulators providing a global solution for vessel-related biosecurity management.

The portal focusses on the management practices employed by a vessel to manage its biofouling and to understand consistently and transparently if the strategies employed by the vessel are sufficient to mitigate the transfer of invasive aquatic species (IAS). The portal is not assessing whether a vessel has an IAS.

Vessel-Check considers 7 aspects of a vessel’s biofouling management (described below). The outcome of each risk metric assessment is articulated to users using a categorical basis of either low (green), medium (orange), or high (red). The indicative risk for each metric is determined from the vessel's biofouling management profile and the information provided by the vessel owner/operator for their vessel(s). The “Overall Risk Assessment” for a vessel represents the average of the seven individual biofouling management risk metrics.

The risk assessment engines used in Vessel-Check have been directly developed with biosecurity regulatory agencies, with trigger points and thresholds within the risk assessment engines based on publicly available peer-reviewed sources.

The indicative risk for a vessel is calculated automatically (based on the information contained in a vessel profile) once the vessel designates in its onboard Automatic Identification System (AIS) system that it intends to enter into a jurisdictions port*. The indicative risk score is re-calculated daily (automatically by the portal) up to 24hrs from the vessel's expected arrival into the intended jurisdiction. After this time, the indicative risk can be re-calculated by the jurisdiction which oversees the intended destination port of the vessel. AIS generated nomination details for a vessel (e.g. destination port and expected arrival time) are refreshed during each update of the AIS data in the Vessel-Check portal, which occurs 4 times a day by default.

A manual nomination process is available for a vessel, to designate its last port of call (LPoC), its destination port, and the expected arrival date/time. The indicative risk assessment is calculated automatically on the submission of the manual nomination (based on the information contained in a vessel profile). Risk assessments associated with manual nominations are also re-calculated daily (automatically by the portal) up to 24hrs from the vessel's expected arrival into the intended jurisdiction. The details of a manual nomination (e.g. destination port and expected arrival time) are fixed following the submission of the manual nomination. If a vessel's operations change (e.g. a different destination port), a new manual nomination will be required to be submitted within the Vessel-Check portal.

The metrics considered by the Vessel-Check portal examine the proactive and reactive management actions planned by a vessel and the implementation of planned management actions to mitigate the transfer of IAS. The biofouling management risk metrics, the intent of their assessment, and the default thresholds used within the risk metric calculations within the Vessel-Check portal are outlined below.

The default thresholds were determined in collaboration with biosecurity management jurisdictions. The default thresholds can be changed by a biosecurity management jurisdiction relative to the legislative requirements of the jurisdiction and/or local environmental management needs. Vessels are encouraged to liaise with the appropriate biosecurity management jurisdiction to understand any specific requirements of the jurisdiction.


*For ports monitored by the jurisdiction. If a port has not been designated by the jurisdiction for monitoring within the portal, the nomination will not be captured and a indicative risk calculation is not possible for the vessels proposed port entry.


1.1 Biofouling Management Plan

On ships and mobile structures, biofouling is well documented to contribute to the spread of invasive aquatic species (IAS) (1). Best practice vessel biofouling management involves the use of vessel-specific Biofouling Management Plan (BMP) and Biofouling Management Record Book (BMRB) to show the implementation of the outlined biofouling management being employed to mitigate the transfer of an IAS (2). A BMP shall describe the biofouling management strategy for the vessel that is sufficiently detailed to allow a master or other appropriate ship’s officer or crew member serving on that vessel to understand and follow the biofouling management strategy.

Vessel-Check examines the presence of a BMP and the currency of the BMP as part of the portal's overall assessment of whether a vessel is mitigating the potential transfer of an IAS to as low as reasonably practicable (ALARP). The intent of assessing the age of the BMP is to ensure that the biofouling management actions being employed are fit for purpose and regularly reviewed for the vessel (i.e. in line with the vessel’s SOLAS survey requirements (3) or the vessels current antifoulant system). The development of a well-structured BMP ensures a ships’ management strategies, contingencies, and actions are documented and can reveal whether standards of practice are being followed (4). The International Maritime Organisation (IMO) provides guidance on the development of BMP’s to mitigate the transfer of IAS (2). Vessel owners/operators are encouraged to seek advice from jurisdictions they intend to visit regarding what is considered best practice for a BMP, or from the classification society of their preference.

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1.1.1 References

(1) Davidson, I., Scianni, C., Hewitt, C., Everett, R., Holm, E., Tamburri, M. and Ruiz, G., 2016. Mini-review: Assessing the drivers of ship biofouling management–aligning industry and biosecurity goals. Biofouling, 32(4), pp.411-428.

(2) IMO [International Maritime Organization] (2011) Guidelines for the control and management of ships’ biofouling to minimize the transfer of invasive aquatic species. Marine Environment Protection Committee, Annex 26, Resolution MEPC.207 (62). London, UK. 25pp

(3) Llyods Register, 2020. Rules and Regulations for the Classification of Ships, accessed 10/09/2020.

(4) Davidson, I.C., Scianni, C., Ceballos, L., Zabin, C., Ashton, G. and Ruiz, G., 2014. Evaluating ship biofouling and emerging management tools for reducing biofouling-mediated species incursions. Report to the Marine Invasive Species Program of the California State Lands Commission, Sacramento.


1.2 Niche Management

The wetted surface area (WSA) of a vessels hull (including the horizontal/vertical hulls) can have a variety of niche areas, including rudders, propellers, stern tubes, intakes, sea-chests, internal seawater piping, bilge keels, thrusters, stabilizers, struts, grates, sacrificial anodes, and other protrusions/recesses. The variety of niche surfaces associated with a ships hull can create hotspots for the accumulation of biofouling on ships (1-4), and the heterogeneity of biofouling accumulation demands differing management to as much as reasonably practicable to reduce the impact of the biofouling accumulation both from a biosecurity and hull efficiency perspective (1, 2, 5).

To aid in understanding if the biofouling management of the vessel is sufficient to mitigate the transfer of an invasive aquatic species (IAS), the Vessel-Check portal determines what proportion of niche areas; defined as susceptible to biofouling by the vessel user; have biofouling management action(s) outlined to control the accumulation of any biofouling. The fewer control measures being utilised to sufficiently manage the vessels biofouling the higher the risk of transferring an IAS.

riskmetricniche1

1.2.1 References

(1) Davidson, I., Scianni, C., Hewitt, C., Everett, R., Holm, E., Tamburri, M. and Ruiz, G., 2016. Mini-review: Assessing the drivers of ship biofouling management–aligning industry and biosecurity goals. Biofouling, 32(4), pp.411-428.

(2) Coutts A.D.M. and Taylor, M.D., 2004. A preliminary investigation of biosecurity risks associated with biofouling on merchant vessels in New Zealand. New Zealand Journal of Marine and Freshwater Research 38: 215–229.

(3) James P, Hayden B., 2000. The potential for the introduction of exotic species by vessel hull fouling: a preliminary study. NIWA report WLG 00/51. Wellington: National Institute of Water and Atmospheric Research.

(4) Davidson I, Brown CW, Sytsma MD, Ruiz GM., 2009. The role of containerships as transfer mechanisms of marine biofouling species. Biofouling. 25:645–655.

(5) Davidson, I.C., Scianni, C., Minton, M.S. and Ruiz, G.M., 2018. A history of ship specialization and consequences for marine invasions, management and policy. Journal of Applied Ecology, 55(4), pp.1799-1811.


1.3 Antifoulant Coating

One of the primary proactive methods for the management of vessel hull biofouling is the application of antifouling coating (AFC) (1). AFC's are designed to prevent or minimise the settlement and attachment of biofouling organisms (1-4, 11), and are formulated to meet different cost and performance requirements (1). There are many types of AFC's but are broadly defined as either biocidal or biocidal-free, with the choice of antifouling coating(s) being based on a vessel’s operational profile. The appropriate technical advice must be obtained from the antifoulant coating manufacturer or supplier to ensure that a coating is capable of meeting or exceeding the planned in-service period for a vessel (1).

Antifouling coatings do not prevent biofouling indefinitely, and the age of an AFC is a good predictor of the biofouling risk (7,10-13), as its efficacy decreases over the working life of the AFC (2,5,6,8,9). The Vessel-Check portal provides an indicative assessment of the risk a vessel’s AFC is not sufficient to mitigate the transfer of an invasive aquatic species (IAS), by calculating the age of the indicated AFC relative to the vessel’s entry into a jurisdiction. The older the AFC in relation to its expected working life, the less likely the AFC is sufficiently mitigating the transfer of an IAS.

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1.3.1 References

(1) Georgiades, E., Growcott, A. and Kluza, D., 2018. Technical guidance on biofouling management for vessels arriving to New Zealand. Ministry for Primary Industries, Manatū Ahu Matua.

(2) AMOG Consulting, 2002. Hull fouling as a vector for the translocation of marine organisms. Phase 3: The significance of the prospective ban on tributyltin antifouling paints on the introduction and translocation of marine pests in Australia. Department of Agriculture, Fisheries and Forestry, Canberra, Australia. 13.

(3) Chambers, L.D., Stokes, K.R., Walsh, F.C., and Wood, R.J.K., 2006. Modern approaches to marine antifouling coatings. Surface and Coatings Technology, 201: 3642–3652.

(4) Dam-Johansen, K., 2004. Antifouling technology – past, present and future steps towards efficient and environmentally friendly antifouling coatings Progress in Organic Coatings, 50(2): 75–104.

(5) Peacock, L., Seaward, K., and Inglis, G.J,. 2010. Review of biosecurity and contaminant risks associated with in-water cleaning. Technical Publication, Department of Agriculture, Fisheries and Forestry (DAFF), Canberra, Australia.

(6) Sylvester, F. and Floerl, O., 2014, Assessment of in-service vessels for biosecurity risk, in Biofouling Methods (1st Edition) Ed. Dobretsov, Thomason, and Wiliams

(7) Floerl, O., Inglis, G. J., and Hayden, B. J., 2005, A Risk-Based Predictive Tool to Prevent Accidental Introductions of Nonindigenous Marine Species, Environmental Management Vol. 35, No. 6, pp. 765–778

(8) Schiff K, Diehl D, Valkirs AO. 2004. Copper emissions from antifouling paint on recreational vessels. Mar Pollut Bull 48:371–377.

(9) Yebra DM, Kiil S, Weinell CE, Dam-Johansen K. 2006. Effects of marine microbial biofilms on the biocide release rate from antifouling paints – a model-based analysis. Prog Org Coat 57:56–66.

(10) Floerl O, Inglis GJ. 2005. Starting the invasion pathway: the interaction between source populations and human transport vectors. Biol Invas 7:589–606.

(11) Piola, R., Dafforn, K., and Johnston, E., 2009). The influence of antifouling practices on marine invasion. Biofouling. 25. 633-44. 10.1080/08927010903063065.

(12) Murray, C.C., Therriault, T.W. and Pakhomov, E., 2013. What lies beneath? An evaluation of rapid assessment tools for management of hull fouling. Environmental Management, 52(2), pp.374-384.

(13) Ashton G, Boos K, Shucksmith R, Cook E (2006) Risk assessment of hull fouling as a vector for marine non-natives in Scotland. Aquat Invasions 1:214–218


1.4 Biofouling Management Implementation (Internal & External Niches)

Implementing practices to control and manage biofouling can have multiple benefits for vessel operators (1-3), including:

· reducing the risk of the transferring of invasive aquatic species (IAS).

· improve a vessel’s hydrodynamic performance, and

· enhancing energy efficiency and reduce air emissions from the vessel.

The Implementation metrics (Internal and External Niche) of the Vessel-Check portal assess the temporal adherence to the planned biofouling management strategies for a vessel in mitigating the transfer of IAS to as low as reasonably practicable (ALARP). The portal examines the Biofouling Management Record Book (BMRB) to determine what management actions (and their outlined temporal interval) have been undertaken for the vessel (as defined in the vessels Biofouling Management Plan (BMP)) relative to the vessel’s entry into a jurisdiction. Where a vessel’s planned biofouling management is being implemented as outlined (in its BMP, according to the indicated implementation interval), the risk of the vessel transferring an IAS is likely to be low.

riskmetricimp1

1.4.1 References

(1) IMO [International Maritime Organization], 2011. Guidelines for the control and management of ships’ biofouling to minimize the transfer of invasive aquatic species. Resolution MEPC.207 (62). London, UK. 25pp

(2) Schultz, M.P., Bendick, J.A., Holm, E.R. and Hertel, W.M., 2011. Economic impact of biofouling on a naval surface ship. Biofouling, 27(1), pp.87-98.

(3) IMO [International Maritime Organization] (2016) Guidelines for the development of a Ship Energy Efficiency Management Plan (SEEMP). Marine Environment Protection Committee, Annex 26, Resolution MEPC.282 (70). London, UK.


1.5 Hull Husbandry

Biofouling management actions to mitigate the transfer of an invasive aquatic species (IAS) can be defined into two broad categories, those actions that are proactive and those that are reactive (1-3). Proactive management involves actions to minimize or prevent attachment or association of biofouling (e.g. the use of antifoulant coatings (AFC) or Marine Growth Prevention Systems, and/or the regular in-water inspection of the biofouling condition on the vessel hull) (1-3). Reactive management actions involve the destruction, inactivation, or removal of organisms from the vessel once they have already accumulated (1-3). Proactive management actions are generally more effective and efficient than reactive actions; however, most effective biofouling management plans incorporate both proactive and reactive management actions (1-3).

The Hull Husbandry metric assesses the frequency of both proactive and reactive management actions used by a vessel to minimise the likelihood of biofouling on the vessel's hull/hull niches transferring an IAS, with the intent to encourage more regular management activities (like in-water inspections) to ensure biofouling risks are being mitigated as much as reasonably practicable (i.e. the lowest risk is returned according to the duration thresholds set out below). The metric examines the Biofouling Management Record Book (BMRB) to determine which proactive or reactive actions have been undertaken relative to the entry date of the vessel into a jurisdiction’s port. The recent implementation of proactive (e.g. in-water inspections) or reactive (e.g. in-water cleaning) actions provides a current understanding of the likely risk posed by any biofouling that may occur on the vessel hull/ hull niches.

Many species that typify the invertebrates likely to foul a vessels hull do not generally reach sexual maturity within 4 weeks of settlement (4). Further, it is unlikely that field officers with a good working knowledge of biofouling groups would be able to identify recruits beyond phylum level until they are at least 4-weeks old (5). Experience taxonomists may not be able to identify 3-week old recruits beyond family level (5). As such, the default time thresholds assumptions within the Hull Husbandry metric have been set considering these findings, and data on key fouling species (6 - 8).

riskmetrichull1

1.5.1 References

(1) Scianni, C., Brown, C., Nedelcheva, R. and Dobroski, N., 2013, September. Hull husbandry practices and biofouling management of vessels operating in California. In 2013 OCEANS-San Diego (pp. 1-4). IEEE.

(2) Tribou, M. and Swain, G., 2010. The use of proactive in-water grooming to improve the performance of ship hull antifouling coatings. Biofouling, 26(1), pp.47-56.

(3) Davidson, I.C., McCann, L.D., Fofonoff, P.W., Sytsma, M.D. and Ruiz, G.M., 2008. The potential for hull‐mediated species transfers by obsolete ships on their final voyages. Diversity and Distributions, 14(3), pp.518-529.

(4) Floerl, O., Wilkens, S., and Inglis, G. 2010. Development of a template for vessel hull inspections and assessment of biosecurity risks to the Kermadec and sub-Antarctic Islands regions. Report prepared for the Department of Conservation. NIWA report no. CHC2010-086.

(5) Floerl, O., Wilkens, S., and Woods, C., 2010. Temporal Development of Biofouling Assemblages, Report prepared for the Department of Agriculture, Fisheries and Forestry. NIWA report no, CHC2012-103.

(6) Mcdonald, J., Serena, T., Serina, L., Coupland, G., McKirdy, S., deLestang, P., and Merwe, J. 2018. It is all in the looks: a rapid field-based visual assessment tool for evaluating the spawning likelihood of the Asian green mussel, Perna viridis (Linnaeus, 1758). Management of Biological Invasions. 9. 10.3391/mbi.2018.9.2.03.

(7) McDonald, J.I., 2012. Detection of the tropical mussel species Perna viridis in temperate Western Australia: possible association between spawning and a marine heat pulse. Aquatic Invasions, 7(4).

(8) Bridgwood, S. and Mcdonald, J. (2014). A likelihood analysis of the introduction of marine pests to Western Australian ports via commercial vessels. Fisheries Research Report No. 259. Department of Fisheries, Western Australia. 212pp.


1.6 Layup/Inactivity

Layup’s are periods of vessel inactivity (typically at either anchor or berthed) and can be characterised by reduced crewing and/or machinery shutdowns (1). Most vessels use an antifoulant coating (AFC) as part of the vessel’s biofouling management. AFC's often require a high frequency of movement, additionally, long periods of inactivity can mitigate the performance of many antifouling coatings; especially self-polishing copolymer AFC's commonly used by merchant vessels (2-4). The longer and more frequently a ship remains stationary (5-6), the more likely it is to potentially accumulate biofouling (6). A single large vessel’s biofouling assemblages (e.g. a 200 m merchant vessel) can represent considerable biomass; if such vessels remain stationary for prolonged periods; and could potentially accumulate more than 20 tonnes of biofouling (8-10). Within the Vessel-Check portal, the potential risk of the vessel transferring an invasive aquatic species (IAS) following any period(s) of layup or inactivity is assessed by determining if there is any appropriate mitigation action(s) (e.g. in-water inspection, in-water clean or dry-dock cleaning) recorded in the vessels Biofouling Management Record Book (BMRB) following the cumulative period(s) of layup or inactivity.

riskmetriclayup1

1.6.1 References

(1) Lloyds Register, 2020. https://www.lr.org/en-au/resources/lay-up-guide-2020/, accessed 10/09/2020

(2) Floerl, O. and Coutts, A., 2009. Potential ramifications of the global economic crisis on human-mediated dispersal of marine non-indigenous species. Marine Pollution Bulletin, 58(11), pp.1595-1598.

(3) Marine Science and Ecology, 2002. Hull Fouling as a Vector for the Translocation of Marine Organisms. Phase III: The Significance of the Prospective Ban on Tributyltin Antifouling Paints on the Introduction and Translocation of Marine Pests in Australia. Ballast Water Research Series, Report No. 15. Department of Agriculture, Fisheries and Forestry Australia, Canberra.

(4) Floerl, O., Inglis, G.J., Marsh, H.M., 2005. Selectivity in vector management: an investigation of the effectiveness of measures used to prevent transport of nonindigenous species. Biological Invasions 7, 459–475.

(5) https://www.marineinsight.com/shipping-news/32-of-offshore-vessels-laid-up-globally-vesselsvalue/ accessed 12/05/2020

(6) https://www.wsj.com/articles/container-ship-operators-idle-ships-in-droves-on-falling-trade-demand-11586359002 accessed 12/05/2020

(7) Floerl, O., Inglis, G.J., 2005. Starting the invasion pathway: the interaction between source populations and human transport vectors. Biological Invasions 7, 589–606.

(8) Hay, C., Dodgshun, T., 1997. Ecosystem transplant? The case of the Yefim Gorbenko. Seafood New Zealand 5, 13–14.

(9) AMOG Consulting, 2002. Hull Fouling as a Vector for the Translocation of Marine Organisms. Phase I: Hull Fouling Research. Ballast Water Research Series, Report No. 14. Department of Agriculture, Fisheries and Forestry, Australia.

(10) Coutts, A., Forrest, B., 2007. Development and application of tools for incursion response: lessons learned from the management of the fouling pest Didemnum vexillum. Journal of Experimental Marine Biology and Ecology 342, 152–164.