Events & Media

How Are the World’s Oceans Doing?
The second annual Ocean Health Index identifies gains and losses over the past year

The 2013 Ocean Health Index (OHI) indicates some gains and some losses in health of the world’s oceans and suggests that providing enough ocean-based protein for human populations is a major and growing challenge.


Prof. Ben Halpern

A collaboration led by Bren professor Ben Halpern and including more than 65 scientists/ocean experts and partnerships among such organizations as the National Center for Ecological Analysis and Synthesis at UCSB, Sea Around Us, Conservation International, National Geographic, and the New England Aquarium, the OHI evaluates the condition of marine and coastal systems in the Exclusive Economic Zones of 221 countries and territories (up from 171 that were included in the 2012 OHI). An EEZ is the region extending 200 miles offshore of a country’s coastline. Scores are assigned in the following ten categories, referred to as “goals” and representing the key ecological, social, and economic benefits that a healthy ocean provides to humans.

Food Provision (Score: 33) ­– The amount of seafood captured or raised in a sustainable way.

  • Artisanal Fishing Opportunities (Score: 95) – The availability of the opportunity to fish to those small-scale fishermen who want to.
  • Natural Products (Score: 31) ­­– How sustainably people are harvesting non-food products from the sea; contributes to local economies and international trade.
  • Carbon Storage (Score: 74) – The carbon stored in natural coastal ecosystems, such as sea grasses, tidal marshes, and mangroves.)
  • Coastal Protection (Score: 69) – The condition and extent of habitats that protect coasts from storm waves and flooding, worth billions of dollars per year.
  • Coastal Livelihoods & Economies (Score: 82) – The availability of local jobs and revenue produced from marine-related industries.
  • Tourism & Recreation (Score: 39) ­– The proportion of the total labor force engaged in the coastal tourism and travel sector, a vital part of a country’s economy.
  • Sense of Place (Score: 60) ­– Evaluates the condition of iconic species and the percent of coastline protected, to indicate the cultural, spiritual, aesthetic, and other intangible benefits to people in a region.
  • Clean Waters (Score: 78) ­– Contamination by trash, nutrients, pathogens and chemicals, with a higher score indicating less pollution.
  • Biodiversity (Score: 85) – Estimates how successfully the richness and variety of marine life is being maintained around the world; includes subsections for species and habitat.
Collectively, the world’s oceans received a score of 65 on a scale of 100 in the new OHI, but while that score clearly indicates that much remains to be done, it is also one number arrived at by averaging the scores for 221 countries and territories included in the index. And, says, Halpern, “Few if any conservation decisions are made at a global scale, so that single number won’t be able to change policy or guide decision making at the scale at which most decisions are made ­– by country or by regions within countries. Rather, it offers a synthetic understanding of the health of the world’s oceans.”

Examining specific goals and/or particular places gives a different kind of information. For instance, in terms of biodiversity, the world earned a score of 85. “That sounds good,” says Halpern, “but looked at from the other side, it means that 15 percent of the world’s species are threatened with extinction.” Further, while Russia scored a 93 and North Korea an 88, the U.S. earned only a 67. That score, which Halpern describes as “counterintuitive,” can reflect several factors, including a country’s relative amount of natural biodiversity – the U.S. has many more species than Russia or North Korea – and also a relative lack of data. The U.S. is data-rich, while North Korea would be classified as data-poor.

“It’s not enough just to have the numbers” says Halpern. “We are deeply committed to ensuring that people understand what they mean as they use the index as a rubric for determining ocean health.”

The 2013 OHI also assessed coastal protection, giving it a score of 69 out of 100 and indicating that further declines are likely, with 45 countries that sit in the annual path of tropical cyclones averaging a score of 52 out of 100. A score below 100 for this goal indicates a decline in area covered by, and condition of, key natural habitats that protect shorelines.

Among the 45 cyclone-prone countries, those having populations exceeding 10 million had an average coastal protection score of only 51, compared to the global average score of 69, and further 1 percent drop is expected in the coming five years. Those numbers indicate the importance of prioritizing conservation and restoration of of these protective coastal systems.

The OHI defines a healthy ocean as one that can sustainably deliver a range of benefits to people now and in the future. A high goal score does not refer to pristine ecosystems, the Ocean Health Index website explains, but rather to a situation in which the maximum sustainable benefit is achieved through methods that do not compromise the ocean’s ability to deliver that benefit in the future.

The lowest global scores were found in three goals: Natural Products (31), Tourism & Recreation (39), and, most notably, Food Provision (33). With experts projecting world demand for protein to grow by 70 percent by 2050 as a result of increasing population and affluence, and arable land becoming increasingly scarce, the ocean will need to supply a much greater percentage of total human protein, making the low score for this goal particularly worthy of attention.

“Seafood is a major source of protein for one-third of the world’s population,” said Daniel Pauly, principal investigator of the Sea Around Us project and leader of the University of British Columbia team of science contributors to OHI. “The score of 33 out of 100 for food provision indicates we are not ready to meet that challenge.”

Halpern hopes that by raising such concerns, the OHI will be useful to decision makers as they make policy and management decisions, and he is pleased to see the index gaining visibility.

“I’m encouraged because people, organizations, and governments are paying attention to the Ocean Health Index and what they can learn from it,” he said. “Not only has the OHI been adopted as an indicator to gauge how well countries are meeting their biodiversity conservation targets, but it is beginning to inform the United Nations World Ocean Assessment and was named by the World Economic Forum as one of two endorsed tools for helping achieve sustainable oceans.”

The goals were created by participating scientists, economists, and sociologists, who reviewed existing studies of what people want and expect from the ocean and then grouped them into the ten goals. Each goal is evaluated on the basis of four dimensions: present status (the goal’s present valued compared to a reference point), trend (the average percent change of a goal’s value over the past five years), pressures (the sum of ecological and social pressures that negatively affect scores for a goal) and resilience (the sum of factors that can positively affect scores for a goal).

“In its second year now, the OHI demonstrates that the areas with the least human

impact have healthier oceans, but it also shows that nations who manage their resources better achieve higher OHI scores,” Halpern said. “We depend on the health of the ocean for many benefits, such as food, livelihood, and tourism, and the OHI indicates that the condition of these benefits needs to be improved in order to provide a healthy thriving ocean for our children and their children.”

Ben Halpern is available at halpern@nceas.ucsb.edu or at 512-517-3724.
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