eOceans evolved from various research projects including eShark, eManta, Great Fiji Shark Count, Global Marine Conservation Assessment, and the Shark Sanctuary Evaluation. Summaries of some of this past work are shown below — click to learn more!

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Review of Shark Sanctuary Policies

Describes what "Shark Sanctuaries" are, and are not, looking at the details of policies implemented and historic shark catches to understand the potential impact to shark populations and their markets, and recommends program evaluation. There appears a need to address bycatch within shark sanctuary regulations, and to collect baseline data that can be used to monitor sanctuary effectiveness. VIEW PAPER


Global evaluation of Shark Sanctuaries using Divers' Observations.

Shark Sanctuaries, as seen through the lens of local scuba diving experts, may be a helpful conservation tool but likely not sufficient in isolation. There is urgent need for higher-resolution data on shark abundance, incidental catch, and markets to direct priority conservation needs and optimize the conservation benefits of existing and future shark sanctuaries. VIEW PAPER


Global status & human use patterns of Manta Rays

The global community of expert scuba divers were recruited to provide data on manta ray populations, the value of ecotourism, and manta rays being fished or in markets. We found that mantas were being fished and marketed, without being reported - often adjacent to areas with valued ecotourism. This suggested that international trade was threatening these gentle giants, and supported listing by CITES in 2013. VIEW PAPER


103 million sharks killed each year - threatens many

With our colleagues at many universities, we found that 103 million sharks are still killed each year, despite improved laws, policies, and education. This is largely due to bycatch - sharks unintentionally caught while fishing other species, like tuna. Importantly, this mortality rate exceeds reproductive rates, meaning that populations will continue to decline. Following from this work, five sharks species were listed by CITES in 2013. VIEW PAPER


Citizen Science in the Guide to Best Practices for diving with Sharks

Chapter 3 is about "Getting Involved in Research", and synthesizes the many ways that ocean explorers, especially scuba divers and leaders of the scuba diving industry, can get involved in shark citizen science. There are many examples of how eOceans diver data have been used. VIEW GUIDE


The Role of the Tourism Industry in Shark Conservation

In the book "Sharks: Conservation, Governance and Management" Chapter 8 is devoted to the role of the Tourism Industry, which can help by generating data and influencing scientific direction, and also by supporting research by allowing scientists access to boats and other logistics. VIEW CHAPTER

Marine Affairs


Management, through policies and laws, govern human uses and impacts on marine ecosystems. These strategies can be used for conservation, to protect and preserve ocean ecosystems. However, management decisions typically weigh societal and economic activities with ecosystem needs, and therefore do not necessarily protect ecosystems from decline or promote recovery.

Therefore, evaluating the success of different management strategies is difficult. 

eOceans has reviewed and evaluated various management strategies. By collaborating with renowned researchers and local experts (e.g., dive instructors), and combining various data sources (e.g, fisheries data), we have amplified the power of Citizen Science to answer relevant and timely questions. 

We have found: 

Citizen Science


eOceans combines the observations and experiences of the global community of ocean explorers to address real-world questions. 

We completed a comprehensive investigation on the value of recreational scuba divers observations to describe marine animal populations, and have combined citizen science data with other information to fill important data gaps. 

We have used event-based censuses (e.g., where every observation is recorded) to describe:

And, one-off interview-style surveys to describe:

Our results have influenced policy and management, including:

Sharks and Rays


Sharks, rays, skates, and sawfish (Elasmobranchs), are an extremely diverse group fish. Therefore, it is impossible to make blanket statements about their value. However, studies have shown that sharks keep other populations in check, remove weak or sick individuals, shift prey habitat, and balance ecosystems. 

Sharks are also important for humans for food, tourism, and intrinsic value.

eOceans' research has engaged professional researchers and citizen scientists to document shark and ray populations – describing contemporary and historic baselines, identifying population risks, and understanding conservation needs.

Findings have included:

Note: The paper investigating inverted biomass pyramids, above, is often mis-cited. This is about scientific divers, and the fact that they count fish that enter their transect AFTER the survey starts, therefore inflating the density of mobile fish compared to that of stationary fish. Faster fish are more likely to enter the transect than stationary or slow fish, and therefore more bias of faster fish (top of the ecosystem). 

We also contributed a chapter on the role of citizen science when conducting shark diving expeditions:

Our works has resulted in significant policy outcomes, including:

Coral Reefs


Coral reefs are spectacularly important living structures. For example, they protect coastal communities from storm surge & erosion, provide habitat & refuge to animals, supply food to humans, offer valuable economic services (e.g., tourism), & supply numerous invaluable benefits, like carbon sequestration & nutrient cycling. 

Coral reefs are fragile and gravely threatened. Many coral reefs have suffered more than 90% coral death in the last couple decades, with very high death rates in 2017.

Threats to corals include nutrient pollution (e.g., farms, human waste), temperature rise, ocean acidification, habitat degradation, aquaculture, sediment loading, invasive species, overfishing, bomb and cyanide fishing, aquarium trade, and African dust carrying disease causing bacteria.  

The film, Chasing Coral, nicely documents the impact of climate change causing coral bleaching and death, and also highlights the need for ocean explorers to share their observations. 

eOceans' researchers efforts have discovered that: