Sink or Swim: The COVID-19 Impact on Environmental Health, Fish Levels and Illicit Maritime Activity

Due to COVID-19, the maritime industry has experienced reduced demand for fresh fish products, international container shipping, research/conservation and naval activity. Although a plus for oceanic health, it could increase illicit maritime activities; impacting fish levels, smuggling and piracy.

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Steve J. Bickley, Alison Macintyre, and Benno Torgler

School of Economics and Finance and Centre for Behavioural Economics, Society and Technology (BEST), Queensland University of Technology, Australia

I. Introduction

The restrictive measures in response to the COVID-19 pandemic is inducing a de-globalisation process of restricted international trade through border lockdowns, enforced social distancing and economy-wide shutdowns of business and normal day-to-day activities1. The World Trade Organisation estimates a fall in world trade between 13% and 32% in 2020 resulting from the disruption of economic activity due to the COVID-19 pandemic2.  Since over 80% of worldwide trade (in total volume) is handled by the maritime industry3, the estimated downturn in global trade suggests a significant decrease in human-based marine activity over the coming months. How will marine ecosystems, fish stock levels and aquatic environments respond?

II. Environmental Health

It is likely that most of us have seen images from Italy depicting the famous canals of Venice, clear and full of aquatic life in recent weeks (see Figure 1 for satellite image changes provided by ESA). The clear waters are primarily due to the reduction in commercial boating activities because of reduced tourism, which in turn has reduced the stirring of sediment. These images have sparked great international interest, with many articles4,5 citing the positive environmental benefits of the current coronavirus crisis, as global human-based activity adapts to health response measures. However, this is only a fraction of the full story.

Figure 1: Canal City of Venice and the Laguna Images Over Time by ESA’s Microsatellite Proba. Source:

As mentioned, seaborne trade accounts for roughly 80% of worldwide trade3. Of this, container ships account for approximately 70% (in total value)6. It is well-known that seagoing ships contribute significantly to total emissions from the transportation sector7. Approximately 3.1 percent of global CO2 emissions8 and 10% of global sulfur emissions9 can be attributed to the maritime industry. In international shipping, high sulfur fuels dominate. Three main environmental and health issues are of concern with respect to maritime sulfur emissions: ocean acidification, climate interference and health problems due to local air pollution10. With reduced global trade and hence, international shipping, it is likely that we will see that these emissions reduce over the coming months. To track progress in this domain, traditional water quality measurements11,12 should be paired with supplementary data collection methods including fuel consumption and satellite data13,14 to provide timely and accurate measurements of marine environmental health. 

III. Fish Levels

The importance of biodiversity in determination of marine ecosystem sustainability and health is an increasingly common topic of discussion15. During the last few centuries of anthropogenic marine activity, marine environments have either perished due to overfishing and subsequent decline in biodiversity16 or species have dispersed beyond their native ranges and transformed ecosystems around the world via global shipping networks17. Marine resources straddling national boundaries are most affected by exploitation18, as are resources within economic zones of weak or small island states with vast maritime territories19. With increasing pressures to turn attention to domestic COVID-19 affairs, it is possible that we will see a spike in illicit fishing activities both within biodiversity hotspots (typically marine-protected areas) and by misreporting of catches as naval academies turn their focus to the lockdown of national maritime territories. Data collected from ship Automatic Identification System (AIS) receivers will be increasingly important to assess the detection of illicit behaviours and out-of-the-ordinary routes20. Novel measures of biodiversity such as ecoacoustics21 could be used in combination with traditional marine research measures of stock assessment to determine fish levels and ongoing biodiversity.

Increased consumer demand for frozen and processed seafood products over fresh-caught products during the COVID-19 pandemic22 could also spell disaster for food security in developing regions largely reliant on aquatic foods such as Africa, Asia and within the Pacific23,24. Subsequently, these regions may be particularly at risk of increased illicit maritime activities including illegal fishing, smuggling, and piracy to combat rising food insecurity and economic fallout. Further, with increased shutdown of ports to international maritime vessels, increased transshipment (less-regulated transfer of stock from ship to ship) is also likely to occur, complicating the fallout from decreased maritime authority presence25. Again, satellite imaging could help enable detection of illicit activity by matching nighttime lights26 on oceanic waters with planned port activities27 to identify any potential inconsistencies between planned and actual maritime behaviours.  

IV. Conclusions

In summary, the environmental effects of the international response to the COVID-19 pandemic on marine ecosystems is not so clear cut as may be portrayed in more mainstream media sources. The lull in international anthropogenic maritime activities (and hence, maritime emissions) relating to decreased global trade are only one aspect of the whole picture. The combined effects of decreased presence of regulatory and law enforcement bodies and increasing food insecurity and economic fallout may actually mean that we do not realise the full environmental benefits of decreased commercial maritime activities over the coming months. A keen, consistent and varied approach must be taken to ensure we can measure and identify any potential illicit maritime activities to enable timely, well-coordinated action for conservation of our natural ocean resources.


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Benno Torgler

Professor, School of Economics and Finance and Centre for Behahavioural Economics, Society and Technology (BEST), Queensland University of Technology

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