Back to Top
8, May, 2008

Global Shark Assessment

Posted in Aqualogy, Eco News, Latest News, Sharks & Rays by saffron

Report the number of Sharks, Rays and Skates you see on every dive you make – even if it’s zero!

To Take Part in the Global Shark Assessment - Click Here

Take part in the on-line Global Shark Assessment Survey.

The Global Shark Assessment is a project that aims to evaluate how shark populations have changed since the beginning of industrial-scale fishing, and make predictions about how these populations will respond to global climate change and to different methods of fishing and protection. They use scuba diver’s observations to census shark populations at different locations around the world.

Leopard Shark Silhoette Ko Phi Phi Dive Site

With overwhelming evidence that shark populations have declined dramatically over the last 50 years, there are still places where some shark species are persisting and even thought to be thriving. Identification of these species and areas is an important step in determining the best method for recovery. In a time when the number of no-take zones and fishing restrictions are increasing, there is a need for acquiring data through alternative, non-extractive methods. All scuba divers/snorkelers that have been in the ocean can help with this effort.

Black Tip Reef Shark

Sharks are an essential component of marine ecosystems; yet, human pressure has put many species at dangerously low abundance levels. Determining what tools (e.g. Marine Protected Areas, coastal development, undisturbed nurseries, fishing regulations, etc.) are best for their survival will be essential for restoring, at least in part, these systems to their former resilience.

Whale Shark Photo Hin Daeng, Ko Lanta, Thailand

Who can help?

ANYONE that has ever dived or snorkeled in the ocean! All ocean going divers (professionals, recreational, and tourists) are candidates for this survey. The on-line survey should be filled out after each dive you make – even if you do not see any sharks. This survey is for dives that you have environmental and sightings information for (either you have just done this dive or it has been recorded in a logbook)- again it must include dives where you did and did not see sharks.

How can I help?

Fill in the online survey – it should only take a few minutes (1-2 minutes per area).

Then, forward this survey to as many divers or dive shops that you can. The more people that fill out this survey, the more we will know about the sharks people see.

What are the results so far?

To see the number of surveys filled out by location and percentage of shark sightings by location please visit the results page.

The Global Shark Assessment – background

Sharks are in trouble worldwide – For these animals to survive, we need to reduce fishing effort by half and have a global ban on shark finning.

Leopard Sharks Swimming at Ko Phi Phi Dive Sites

Dr. Myers and colleagues launched the Global Shark Assessment in October of 2003 to assess how global shark populations have changed since the beginning of industrial scale fishing, and to make predictions about how these populations will respond to global climate change and to different methods of fishing.

Sharks (and other elasmobranches) are vulnerable to fishing pressure because they are long-lived, slow to mature, and produce few offspring compared with most other fish. Hence, directed fishing can much more quickly decimate sharks than other fish species.

Whale Shark Smile at Ko Haa, Ko Lanta, Thailand

Sharks are also often taken as bycatch in multi-species fisheries in which the target species are quick to replenish themselves while the sharks are not. This occurs in pelagic longline fisheries that target highly productive tuna species, but catch great numbers of sharks. It also occurs along southeastern U.S. coast where there is a bottom longline fishery that is targeted at sharks, but that catches many different shark species with different vulnerabilities to over-fishing. In these fisheries, the slow-to-reproduce shark species may be fished to extinction, while the more productive fishes continue to drive the industry.

“We need to find out how general shark declines are across all the world’s oceans,” says Myers. As fishing pressure is intense everywhere, the situation he and researcher Julia Baum detected in the Gulf of Mexico may prove to be part of a general phenomena.

Manta Ray at Hin Daeng, Ko Lanta, Thailand

Currently, there exist both substantial amounts of unanalyzed data on sharks and a large number of dedicated shark biologists. However, these two key resources have not, as yet, been utilized to their full potential. The Global Shark Assessment will put the data and biological experts together with a team of modeling and statistical experts to produce a global assessment, with an emphasis on producing results in a form that is accessible to decision makers.

Specifically, the Global Shark Assessment will:

  • Estimate the pre-exploitation population sizes
  • Estimate current population parameters
  • Predict the outcome of current management practices
  • Effectively communicate the results
  • Recommend the practices necessary to ensure shark survival

The potential benefits of shark conservation are great. In protecting a host of large, charismatic, but particularly vulnerable species, shark conservation offers the opportunity to protect not just sharks, but the myriad other species and ecosystems with which and in which sharks interact. Hence, at stake are not merely sharks, but our still vastly misunderstood marine realm.

“It will be impossible to set management and restoration goals for these shark species without a clear understanding of how much we have lost. Our studies provide this missing baseline,” says Baum.

Take part in the on-line Global Shark Assessment Survey.




On 27th April 2008, Christine Ward-Paige from Global Shark Assessment joined us on the Scubafish Dive Boat for a dive trip to Hin Daeng so that she could perform a Shark Assessment in our area.

It was with great pleasure that I dived with her and showed her her first Manta Ray!

Christine was very enthusiastic about being able to research Sharks in our area and said “Thank you soooooo mmmuuuch for today. It was such a memorable experience- my first of a lot of things (crinoids, crown of thorns and MANTA!). It was really helpful for me to see what will/won’t work and to talk to the divers after diving.”

We hope that the Global Shark Assessment will help us to learn more about Sharks and how we can protect them.

A final message from Christine: “Please, if you’ve been diving in the ocean, take the time to fill out a survey- it will really help us know more about sharks.”


Pingback: Shark Guardian leaps on to Koh Lanta with eShark updates and education

Leave a Comment

%d bloggers like this: